213 results on '"Transcriptional Regulation"'
Search Results
2. Long non-coding RNAs with essential roles in neurodegenerative disorders.
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Wandi Xiong, Lin Lu, and Jiali Li
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- 2024
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3. 甘蓝型油菜苗期响应渍害胁迫的生理调控机制.
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周香玉, 徐劲松, 谢伶俐, 许本波, and 张学昆
- Abstract
Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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- View/download PDF
4. Target Finder of Transcription Factor (TFoTF): a novel tool to predict transcription factor‐targeted genes in cancer.
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Wang, Fanchen, Xu, Xiaolin, Li, Xin, Yuan, Jia, Gao, Xuzhu, Wang, Chenglong, Guan, Wencai, and Xu, Guoxiong
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Transcription factors (TFs) are key players in the regulation of gene transcription in mammalian cells. Although high‐throughput screening can be used to identify differentially expressed genes between comparable groups, the precision of the corresponding datasets is far from optimal. Here, we establish Target Finder of Transcription Factor (TFoTF), a method for the prediction of TF‐targeted genes from genomic and cancer‐related transcriptomic data. TFoTF can identify potential TF‐targeted genes in large cancer datasets and efficiently estimate correlations between TFs and their targeted genes with a significant level of specificity, sensitivity, and precision. Overall, TFoTF is an easy‐to‐use tool that can be utilized to generate testable hypotheses in the context of cancer research projects. [ABSTRACT FROM AUTHOR]
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- 2023
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5. Characterization of the promoter region of the murine Catsper2 gene.
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Contreras‐Marciales, Andrea del Pilar, López‐Guzmán, Sergio Federico, Benítez‐Hess, María Luisa, Oviedo, Norma, and Hernández‐Sánchez, Javier
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PROMOTERS (Genetics) ,SPERMATOGENESIS ,DELETION mutation ,MALE infertility ,P16 gene ,BINDING sites ,FUNCTIONAL analysis ,CALCIUM channels - Abstract
CATSPER2 (Cation channel sperm‐associated protein 2) protein, which is part of the calcium CATSPER channel located in the membrane of the flagellar principal piece of the sperm cell, is only expressed in the testis during spermatogenesis. Deletions or mutations in the Catsper2 gene are associated with the deafness‐infertility syndrome (DIS) and non‐syndromic male infertility. However, the mechanisms by which Catsper2 is regulated are unknown. Here, we report the characterization of the promoter region of murine Catsper2 and the role of CTCF and CREMτ in its transcription. We report that the promoter region has transcriptional activity in both directions, as determined by observing luciferase activity in mouse Sertoli and GC‐1 spg transfected cells. WGBS data analysis indicated that a CpG island identified in silico is non‐methylated; Chromatin immunoprecipitation (ChIP)‐seq data analysis revealed that histone marks H3K4me3 and H3K36me3 are present in the promoter and body of the Catsper2 gene respectively, indicating that Catsper2 is subject to epigenetic regulation. In addition, the murine Catsper2 core promoter was delimited to a region between −54/+189 relative to the transcription start site (TSS), where three CTCF and one CRE binding site were predicted. The functionality of these sites was determined by mutation of the CTCF sites and deletion of the CRE site. Finally, ChIP assays confirmed that CREMτ and CTCF bind to the Catsper2 minimal promoter region. This study represents the first functional analysis of the murine Catsper2 promoter region and the mechanisms that regulate its expression. [ABSTRACT FROM AUTHOR]
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- 2022
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6. Liquiritin exerts psoriasis therapy and prevention by regulating the YY1/RBP3 axis.
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Deng, Guoshu, Zhang, Yulin, Song, Jiankun, Ma, Xiaoxuan, Luo, Yue, Fei, Xiaoya, Jiang, Jingsi, Ru, Yi, Tai, Zongguang, Zhu, Quangang, Ma, Xin, Kuai, Le, Li, Bin, Zhang, Ying, and Luo, Ying
- Abstract
Psoriasis (PSO) poses a global health threat. The current research challenge in PSO is relapse. Liquiritin (LIQ), a major active compound from Glycyrrhiza inflata Batalin, has multiple pharmacological properties, including anti-inflammatory and anti-proliferative. Nonetheless, the precise mechanisms underlying LIQ's therapeutic actions in PSO and prevention abilities remain elusive. The present study aimed to delve into the potential to treat and prevent PSO and the mechanism of LIQ. The anti-inflammatory and anti-proliferative effects of LIQ were studied in vitro with the HaCaT cell line. Then, Transcriptional analysis and bioinformatic analysis were used to determine the internal associations of the target set. Subsequently, functional experiment, luciferase report assay, ChIP-PCR, and immunohistochemical validation of clinical samples were performed to investigate the mechanism of LIQ. Finally, the anti-psoriatic effects and prevention abilities of LIQ were verified in vivo with imiquimod (IMQ)-induced PSO-like mouse models. Here, we identified differentially expressed genes in LIQ-stimulated HaCaT cells and Retinol-Binding Protein 3 (RBP3) as the core target, whereas YY1 was a predicted upstream transcription factor of RBP3. The YY1/RBP3 axis was obviously altered after administering LIQ at optimal doses of 20 μM in vitro and 100 µg/ml in vivo. LIQ can significantly inhibit the progression of PSO in vivo. Notably, LIQ also prevented the relapse of psoriatic lesions induced by the second round of low-dose IMQ. Mechanistically, we observed that LIQ could increase the promotion of YY1 for RBP3 by enhancing the binding affinity between them. These findings revealed that the YY1/RBP3 axis is a potential psoriatic target, and LIQ is a promising and innovative therapeutic candidate for the treatment and prevention of PSO. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2024
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7. Varying concentrations of ethephon induce antioxidant defences and cell wall degradation to regulate storage quality of fresh-cut lotus root.
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Wang, Hongxun, Wang, Haoyu, Yi, Yang, Hou, Wenfu, Wang, Limei, Ai, Youwei, and Min, Ting
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ETHEPHON ,REACTIVE oxygen species ,GENETIC transcription regulation ,MICROBIAL diversity ,MICROBIAL growth - Abstract
This study examined the impact of varying concentrations of ethephon (ET) immersion on the storage quality of fresh-cut lotus root. Compared to the 0.1%, the 0.8% and 1.6% ET groups inhibited phenolic oxidation and showed stronger antioxidant and reactive oxygen species balancing capacity during early storage, which led to better browning inhibition. During the early storage period, varying concentrations of ET treatments were inversely associated with microbial growth, and Pseudomonas as the major microorganism was significantly inhibited. During the post-storage period, the ET group exacerbated cell wall metabolism, contributed to the softening of lotus root slices. Additionally, ET stimulated enhanced respiration and reduced total soluble solids content as ET concentration increased. The heightened expression of NnERF in the late storage stage suggested a potential link to the regulation of root quality deterioration. Both browning inhibition and quality deterioration promotion exhibited gradient shifts in accordance with ET concentration. Combined with DNA affinity purification sequencing technology to identify the presence of motifs that bind specifically to ERF1B in lotus root, and screening for the possible target genes NnPL18 and NnACO that may be regulated by NnERF1B-like (104610030), it further suggests that NnERF1B-like (104610030) may mediate the process of lotus root flake softening and ethylene biosynthesis. [Display omitted] • Elevated concentrations of ethephon were effective in inhibiting early browning. • Ethephon inhibited Pseudomonas retarded early quality deterioration. • Elevated concentrations of ethephon exacerbated the late softening. • NnERF1B-like may target regulation softening and ethylene biosynthesis. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Elucidating the molecular mechanisms in phytohormones-induced alleviation of postharvest physiological deterioration in cassava tuberous roots.
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Ye, Xiaoxue, Xie, Zhengnan, Zeng, Liwang, Ding, Zehong, Tie, Weiwei, Yan, Yan, Huo, Kaisen, Ma, Jianxiang, Li, Chaochao, Yan, Fei, Chen, Yinhua, Ye, Jianqiu, and Hu, Wei
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TROPICAL crops ,FOOD crops ,GENETIC transcription regulation ,GERMPLASM ,GIBBERELLIC acid ,CASSAVA - Abstract
Cassava is a staple food crop in tropical regions, serving as a significant source of carbohydrates. However, rapid postharvest physiological deterioration (PPD) significantly limits the shelf life and utilization of cassava. Despite its importance, the overlapping molecular mechanisms underlying phytohormones-induced PPD alleviation in cassava tuberous roots remain unknown. In this study, the phytohormones ethephon (ET), gibberellic acid (GA), and methyl jasmonate (MeJA) were applied to cassava tuberous roots after harvest. These treatments led to significantly reduced H 2 O 2 accumulation and alleviation of PPD. Transcriptomic analysis revealed shared functions, including transcriptional regulation and oxidoreductase activity, among differentially expressed genes (DEGs) affected by ET, GA, or MeJA. A total of 305 genes encoding antioxidant enzymes were systematically identified, with 151 responsive to phytohormone treatments across ten families. Notably, the expression of 10 Glutathione S-transferase (GST) genes was induced by all three phytohormone treatments, while their expression was suppressed in the absence of phytohormones during PPD. By using co-expression network analysis, DNA-binding motif analysis, and experimental validation using yeast one-hybrid and dual-luciferase assays, a regulatory network involving MeMYB102 and MeZAT11 transcription factors (TFs) that directly promote the expression of MeGST42 , MeGST43 , MeGST44 , and MeGST46 was established. Overall, this study enhances the understanding of the overlapping molecular mechanisms underlying phytohormones-induced alleviation of PPD in cassava, thereby providing genetic resources for developing PPD-resistant cassava. • ET, GA, and MeJA reduce H 2 O 2 accumulation, alleviating cassava PPD. • Shared mechanisms in cassava PPD alleviation by phytohormones were unveiled. • Hormone-induced GSTs expression highlights their role in PPD alleviation. • Regulatory pathway MeMYB102/MeZAT11− MeGST42/43/44/46 was revealed. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Transcriptional regulation of Znt family members znt4, znt5 and znt10 and their function in zinc transport in yellow catfish (Pelteobagrus fulvidraco).
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Liu, Lu-Lu, Song, Chang-Chun, Abu-Elala, Nermeen, Tan, Xiao-Ying, Zhao, Tao, Zheng, Hua, Yang, Hong, and Luo, Zhi
- Abstract
The study characterized the transcriptionally regulatory mechanism and functions of three zinc (Zn) transporters (znt4 , znt5 and znt10) in Zn
2+ metabolism in yellow catfish (Pelteobagrus fulvidraco), commonly freshwater fish in China and other countries. We cloned the sequences of znt4 promoter, spanning from −1217 bp to +80 bp relative to TSS (1297 bp); znt5 , spanning from −1783 bp to +49 bp relative to TSS (1832 bp) and znt10 , spanning from −1923 bp to +190 bp relative to TSS (2113 bp). In addition, after conducting the experiments of sequential deletion of promoter region and mutation of potential binding site, we found that the Nrf2 binding site (−607/−621 bp) and Klf4 binding site (−5/−14 bp) were required on znt4 promoter, the Mtf-1 binding site (−1674/−1687 bp) and Atf4 binding site (−444/−456 bp) were required on znt5 promoter and the Atf4 binding site (−905/−918 bp) was required on znt10 promoter. Then, according to EMSA and ChIP, we found that Zn2+ incubation increased DNA affinity of Atf4 to znt5 or znt10 promoter, but decreased DNA affinity of Nrf2 to znt4 promoter, Klf4 to znt4 promoter and Mtf-1 to znt5 promoter. Using fluorescent microscopy, it was revealed that Znt4 and Znt10 were located in the lysosome and Golgi, and Znt5 was located in the Golgi. Finally, we found that znt4 knockdown reduced the zinc content of lysosome and Golgi in the control and zinc-treated group; znt5 knockdown reduced the zinc content of Golgi in the control and zinc-treated group and znt10 knockdown reduced the zinc content of Golgi in the zinc-treated group. High dietary zinc supplement up-regulated Znt4 and Znt5 protein expression. Above all, for the first time, we revealed that Klf4 and Nrf2 transcriptionally regulated the activities of znt4 promoter; Mtf-1 and Atf4 transcriptionally regulated the activities of znt5 promoter and Atf4 transcriptionally regulated the activities of znt10 promoter, which provided innovative regulatory mechanism of zinc transporting in yellow catfish. Our study also elucidated their subcellular location, and regulatory role of zinc homeostasis in yellow catfish. • We cloned and characterized znt4, znt5 and znt10 promoters from fish. • Required Nrf2, Klf4, Atf4 and Mtf-1 binding sites were found in these promoters. • Nrf2, Klf4, Atf4 and Mtf-1 mediated zinc-induced regulation of znt4, znt5 and znt10. • Znt4 was located in lysosome and Golgi, and Znt5 and Znt10 in Golgi. • High dietary zinc supplement up-regulated Znt4 and Znt5 protein expression. [ABSTRACT FROM AUTHOR]- Published
- 2024
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10. E2F5 promotes proliferation and invasion of gastric cancer through directly upregulating UBE2T transcription.
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Li, Lina, Liu, Jie, and Huang, Wei
- Abstract
The underlying mechanisms of E2F5 upregulation and its pro-tumor functions have not been elucidated in gastric cancer (GC). Here, the expression, prognostic value, mutation status, and promoter methylation of E2F5 were evaluated. The effects of E2F5 depletion on cell proliferation and invasion in GC, were also assessed through in vitro experiments. Additionally, gene set enrichment analysis (GSEA) was applied to analyze the potential downstream regulator of E2F5. The study also assessed the correlation and transcription regulation between E2F5 and UBE2T. Finally, the roles of UBE2T in E2F5-related pro-tumor functions were examined. The findings revealed that E2F5 was upregulated and showed remarkable association with pathological variables and prognosis. Hypomethylation of the E2F5 promoter predicted poor prognosis and partially caused E2F5 upregulation in GC. E2F5 knockdown significantly inhibited the proliferation and invasion of GC cells. E2F5 had a significant positive correlation with UBE2T in GC. Mechanistically, E2F5 promoted UBE2T transcription and UBE2T overexpression reversed the effects of E2F5 depletion on the proliferation and invasion of cells in GC. Taken together, this study originally confirmed the upregulation of E2F5 in GC, revealed that E2F5 can directly upregulate UBE2T transcription, and subsequently promote the malignant progression, which highlights that the E2F5/UBE2T axis can potentially be used in the diagnosis and treatment of GC. [ABSTRACT FROM AUTHOR]
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- 2022
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11. Polycomb Repressive Complex 2-Mediated H3K27 Trimethylation Is Required for Pathogenicity in Magnaporthe oryzae.
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Wu, Zhongling, Qiu, Jiehua, Shi, Huanbin, Lin, Chuyu, Yue, Jiangnan, Liu, Zhiquan, Xie, Wei, Naqvi, Naweed I., Kou, Yanjun, and Tao, Zeng
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HISTONE methylation ,HISTONES ,DROUGHT tolerance ,GENETIC transcription regulation - Abstract
Polycomb repressive complex 2 (PRC2) contributes to catalyze the methylation of histone H3 at lysine 27 and plays vital roles in transcriptional silencing and growth development in various organisms. In Magnaporthe oryzae , histone H3K27 is found to associate with altered transcription of in planta induced genes. However, it is still unknown whether and how H3K27me3 modification is involved in pathogenicity to rice and stress response. In this study, we found that core subunits of PRC2, Kmt6-Suz12-Eed, were required for fungal pathogenicity to rice in M. oryzae. Kmt6-Suz12-Eed localized in the nuclei and was necessary for the establishment of H3K27me3 modification. With ChIP-seq analysis, 9.0% of genome regions enriched with H3K27me3 occupancy, which corresponded to 1033 genes in M. oryzae. Furthermore, deletion of Kmt6 , Suz12 or Eed altered genome-wide transcriptional expression, while the de-repression genes in the Δ kmt6 strain were highly associated with H3K27me3 occupancy. Notably, plenty of genes which encode effectors and secreted enzymes, secondary metabolite synthesis genes, and cell wall stress-responsive genes were directly occupied with H3K27me3 modification and de-repression in the Δ kmt6 strain. These results elaborately explained how PRC2 was required for pathogenicity, which is closely related to effector modulated host immunity and host environment adaption. [ABSTRACT FROM AUTHOR]
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- 2022
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12. Ethylene is the key phytohormone to enhance arsenic resistance in Arabidopsis thaliana.
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Zou, Yiping, Liu, Yaping, Li, Wei, Cao, Qingqing, Wang, Xue, Hu, Zhubing, Cai, Qingsheng, and Lou, Laiqing
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ARSENIC ,TRANSCRIPTION factors ,ETHYLENE ,ARABIDOPSIS thaliana ,GENE expression ,CHELATION - Abstract
The toxic metalloid arsenic is prevalent in the environment and poses a threat to nearly all organisms. However, the mechanism by which phytohormones modulate arsenic resistance is not well-understood. Therefore, we analyzed multiple phytohormones based on the results of transcriptome sequencing, content changes, and related mutant growth under arsenic stress. We found that ethylene was the key phytohormone in Arabidopsis thaliana response to arsenic. Further investigation showed the ethylene-overproducing mutant eto1–1 generated less malondialdehyde (MDA), H 2 O 2 , and O 2
•- under arsenic stress compared to wild-type, while the ethylene-insensitive mutant ein2–5 displayed opposite patterns. Compared to wild-type, eto1–1 accumulated a smaller amount of arsenic and a larger amount of non-protein thiols. Additionally, the immediate ethylene precursor, 1-aminocyclopropane-1-carboxylic acid (ACC), enhanced resistance to arsenic in wide-type, but not in mutants with impaired detoxification capability (i.e., cad1–3 , pad2–1 , abcc1abcc2), which confirmed that ethylene regulated arsenic detoxification by enhancing arsenic chelation. ACC also upregulated the expression of gene(s) involved in arsenic detoxification, among which ABCC2 was directly transcriptionally activated by the ethylene master transcription factor ethylene-insensitive 3 (EIN3). Overall, our study shows that ethylene is the key phytohormone to enhance arsenic resistance by reducing arsenic accumulation and promoting arsenic detoxification at both physiological and molecular levels. [Display omitted] • Ethylene is the key phytohormone that alleviates arsenic stress in Arabidopsis thaliana. • Ethylene enhances arsenic chelation to promote arsenic detoxification. • Ethylene-insensitive 3 (EIN3) regulated the expression of gene(s) involved in arsenic detoxication. [ABSTRACT FROM AUTHOR]- Published
- 2024
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13. A single-cell profile reveals the transcriptional regulation responded for Abelmoschus manihot (L.) treatment in diabetic kidney disease.
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Wu, Chenhua, Tang, Haitao, Cui, Xu, Li, Nan, Fei, Jingjin, Ge, Haitao, Wu, Liang, Wu, Jie, and Gu, Harvest F.
- Abstract
• Huangkui capsule (HKC) has a significant efficacy in treatment of diabetic kidney disease. • HKC is a format of ethanol extract of Abelmoschus manihot (L.) and its bioactive ingredients mainly include seven flavonoids. • A comprehensive single-cell RNA sequencing analysis of kidneys in db/db mice with HKC administration is done. • The key receptors and regulons in four types of renal cells responded to the administration of HKC and the flavonoids of A. manihot are identified. Huangkui capsule (HKC), as an ethanol extract of Abelmoschus manihot (L.), has a significant efficacy in treatment of the patients with diabetic kidney disease (DKD). The bioactive ingredients of HKC mainly include the flavonoids such as rutin, hyperoside, hibifolin, isoquercetin, myricetin, quercetin and quercetin-3-O-robinobioside. To explore the molecular mechanisms of A. manihot in treatment of DKD. A single-cell RNA sequencing analysis of kidneys in db/db mice with and without HKC administration. Urinary biochemical and histopathological examination in C57BL/6 and db/db mice of DKD and HKC groups was done. Single-cell RNA sequencing pipeline was then performed. The regulatory mechanisms of seven flavonoids in HKC were revealed by cell communication, prediction of transcription factor regulatory network, and molecular docking. By constructing ligand-receptor regulatory network and performing molecular docking between 75 receptors with different activities and seven flavonoids. 11 key receptors in 4 cell types (segment 3 proximal convoluted tubular cell, ascending limbs of the loop of Henle, distal convoluted tubule, and T cell) in kidneys were found to be directly interacted with HKC. The interactions regulated 8 downstream regulons. The docking receptors in T cell led to transcriptional event differences in the regulons such as Cebpb, Rel, Tbx21 and Klf2 and consequently affected the activation, differentiation, and infiltration of T cell, while the receptors Tgfbr1 and Ldlr in stromal cells of kidneys were closely associated with the downstream transcriptional events of renal injury and proteinuria in DKD. The current study provides novel information of the key receptors and regulons in renal cells for a better understanding of the cell type specific molecular mechanisms of A. manihot in treatment of DKD. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Lysosomes: multifunctional compartments ruled by a complex regulatory network.
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Martinez-Fabregas, Jonathan, Tamargo-Azpilicueta, Joaquin, and Diaz-Moreno, Irene
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LYSOSOMES ,HOMEOSTASIS ,IMMUNOREGULATION ,CELLULAR control mechanisms ,HYDROLASES ,METABOLIC regulation - Abstract
More than 50 years have passed since Nobel laureate Cristian de Duve described for the first time the presence of tiny subcellular compartments filled with hydrolytic enzymes: the lysosome. For a long time, lysosomes were deemed simple waste bags exerting a plethora of hydrolytic activities involved in the recycling of biopolymers, and lysosomal genes were considered to just be simple housekeeping genes, transcribed in a constitutive fashion. However, lysosomes are emerging as multifunctional signalling hubs involved in multiple aspects of cell biology, both under homeostatic and pathological conditions. Lysosomes are involved in the regulation of cell metabolism through the mTOR/TFEB axis. They are also key players in the regulation and onset of the immune response. Furthermore, it is becoming clear that lysosomal hydrolases can regulate several biological processes outside of the lysosome. They are also implicated in a complex communication network among subcellular compartments that involves intimate organelle-to-organelle contacts. Furthermore, lysosomal dysfunction is nowadays accepted as the causative event behind several human pathologies: low frequency inherited diseases, cancer, or neurodegenerative, metabolic, inflammatory, and autoimmune diseases. Recent advances in our knowledge of the complex biology of lysosomes have established them as promising therapeutic targets for the treatment of different pathologies. Although recent discoveries have started to highlight that lysosomes are controlled by a complex web of regulatory networks, which in some cases seem to be cell- and stimuli-dependent, to harness the full potential of lysosomes as therapeutic targets, we need a deeper understanding of the littleknown signalling pathways regulating this subcellular compartment and its functions. [ABSTRACT FROM AUTHOR]
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- 2022
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15. Expression analysis of phosphate induced genes in contrasting maize genotypes for phosphorus use efficiency.
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Vasconcelos, M. J. V., Figueiredo, J. E. F., Oliveira, M. F., Parentoni, S. N., Marriel, I. E., and Raghothama, K. G.
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GENE expression ,LOCUS (Genetics) ,GENOTYPES ,GENES ,ACID soils ,PLANT nutrients - Abstract
Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
- Full Text
- View/download PDF
16. Molecular mechanisms regulating the catabolic and electrochemical activities of Shewanella oneidensis MR-1.
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Kouzuma, Atsushi
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SHEWANELLA oneidensis ,RESPIRATION ,CHARGE exchange ,ELECTRIC currents ,CELL physiology ,MICROBIAL fuel cells - Abstract
Electrochemically active bacteria (EAB) interact electrochemically with electrodes via extracellular electron transfer (EET) pathways. These bacteria have attracted significant attention due to their utility in environmental-friendly bioelectrochemical systems (BESs), including microbial fuel cells and electrofermentation systems. The electrochemical activity of EAB is dependent on their carbon catabolism and respiration; thus, understanding how these processes are regulated will provide insights into the development of a more efficient BES. The process of biofilm formation by EAB on BES electrodes is also important for electric current generation because it facilitates physical and electrochemical interactions between EAB cells and electrodes. This article summarizes the current knowledge on EET-related metabolic and cellular functions of a model EAB, Shewanella oneidensis MR-1, focusing specifically on regulatory systems for carbon catabolism, EET pathways, and biofilm formation. Based on recent developments, the author also discusses potential uses of engineered S. oneidensis strains for various biotechnological applications. [ABSTRACT FROM AUTHOR]
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- 2021
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17. Histone H3K36me3 mediates the genomic instability of Benzo[a]pyrene in human bronchial epithelial cells.
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Chen, Shen, Zhang, Zhengbao, Peng, Honghao, Jiang, Shuyun, Xu, Chi, Ma, Xingyu, Zhang, Liying, Zhou, Hao, Xing, Xiumei, Chen, Liping, Wang, Qing, Chen, Wen, and Li, Daochuan
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GENE expression ,PYRENE ,EPITHELIAL cells ,POISONS ,HISTONE methylation ,HOMEOSTASIS - Abstract
Histone modifications maintain genomic stability and orchestrate gene expression at the chromatin level. Benzo [a]pyrene (BaP) is the ubiquitous carcinogen widely spread in the environment, but the role and regulatory mechanism of histone modification in its toxic effects remain largely undefined. In this study, we found a dose-dependent reduction of histone H3 methylations at lysine4, lysine9, lysine27, lysine36 in HBE cells treated with BaP. We observed that inhibiting H3K27 and H3K36 methylation impaired cell proliferation, whereas the loss of H3K4, H3K9, H3K27, and H3K36 methylation led to increased genomic instability and delayed DNA repair. H3K36 mutation at both H3.1 and H3.3 exhibited the most significant impacts. In addition, we found that the expression of SET domain containing 2 (SETD2), the unique methyltransferase catalyzed H3K36me3, was downregulated by BaP dose-dependently in vitro and in vivo. Knockdown of SETD2 aggravated DNA damage of BaP exposure, which was consistent with the effects of H3K36 mutation. With the aid of chromatin immunoprecipitation (ChIP) -seq and RNA-seq, we found that H3K36me3 was responsible for transcriptional regulation of genes involved in pathways related to cell survival, lung cancer, metabolism and inflammation. The enhanced enrichment of H3K36me3 in genes (CYP1A1, ALDH1A3, ACOXL, WNT5A, WNT7A, RUNX2, IL1R2) was positively correlated with their expression levels, while the reduction of H3K36me3 distribution in genes (PPARGC1A, PDE4D, GAS1, RNF19A, KSR1) were in accordance with the downregulation of gene expression. Taken together, our findings emphasize the critical roles and mechanisms of histone lysine methylation in mediating cellular homeostasis during BaP exposure. [Display omitted] • BaP leads to a reduction in global methylation of H3 at specific lysine residues. • H3K36me3 plays a crucial role in maintaining genomic stability upon BaP exposure. • Reduction of SETD2 induced by BaP is responsible for dysregulation of H3K36me3. • H3K36me3 mediates BaP-induced toxicity by regulating cancer-related pathways. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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18. Epithelial/mesenchymal heterogeneity of high‐grade serous ovarian carcinoma samples correlates with miRNA let‐7 levels and predicts tumor growth and metastasis.
- Author
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Chirshev, Evgeny, Hojo, Nozomi, Bertucci, Antonella, Sanderman, Linda, Nguyen, Anthony, Wang, Hanmin, Suzuki, Tise, Brito, Emmanuel, Martinez, Shannalee R., Castañón, Christine, Mirshahidi, Saied, Vazquez, Marcelo E., Wat, Pamela, Oberg, Kerby C., Ioffe, Yevgeniya J., and Unternaehrer, Juli J.
- Abstract
Patient‐derived samples present an advantage over current cell line models of high‐grade serous ovarian cancer (HGSOC) that are not always reliable and phenotypically faithful models of in vivo HGSOC. To improve upon cell line models of HGSOC, we set out to characterize a panel of patient‐derived cells and determine their epithelial and mesenchymal characteristics. We analyzed RNA and protein expression levels in patient‐derived xenograft (PDX) models of HGSOC, and functionally characterized these models using flow cytometry, wound healing assays, invasion assays, and spheroid cultures. Besides in vitro work, we also evaluated the growth characteristics of PDX in vivo (orthotopic PDX). We found that all samples had hybrid characteristics, covering a spectrum from an epithelial‐to‐mesenchymal state. Samples with a stronger epithelial phenotype were more active in self‐renewal assays and more tumorigenic in orthotopic xenograft models as compared to samples with a stronger mesenchymal phenotype, which were more migratory and invasive. Additionally, we observed an inverse association between microRNA let‐7 (lethal‐7) expression and stemness, consistent with the loss of let‐7 being an important component of the cancer stem cell phenotype. We observed that lower let‐7 levels were associated with the epithelial state and a lower epithelial mesenchymal transition (EMT) score, more efficient spheroid and tumor formation, and increased sensitivity to platinum‐based chemotherapy. Surprisingly, in these HGSOC cells, stemness could be dissociated from invasiveness: Cells with lower let‐7 levels were more tumorigenic, but less migratory, and with a lower EMT score, than those with higher let‐7 levels. We conclude that let‐7 expression and epithelial/mesenchymal state are valuable predictors of HGSOC proliferation, in vitro self‐renewal, and tumor burden in vivo. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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19. The function of Spt3, a subunit of the SAGA complex, in PGK1 transcription is restored only partially when reintroduced by plasmid into taf1 spt3 double mutant yeast strains.
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Ryo Iwami, Naoki Takai, and Tetsuro Kokubo
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TRANSGENIC organisms ,RNA analysis ,YEAST ,SACCHAROMYCES cerevisiae - Abstract
In Saccharomyces cerevisiae, class II gene promoters contain two classes of TATA elements: the TATA box and the TATA-like element. Functional loss of TFIID and SAGA transcription complexes selectively impacts steady-state mRNA levels expressed from TATA-like element-containing (i.e., TATA-less) and TATA box-containing promoters, respectively. While nascent RNA analysis has revealed that TFIID and SAGA are required for both types of promoters, the division of their roles remains unclear. We show here that transcription from the PGK1 promoter decreased in some cases by more than half after disruption of the TATA box or SPT3 (spt3Δ), whereas spt3Δ did not affect transcription from the TATA-less promoter, consistent with the prevailing view that Spt3 functions specifically in a TATA box-dependent manner. Transcription from this promoter was abolished in the spt3Δ taf1-N568Δ strain but unaffected in the taf1-N568Δ strain, regardless of TATA box presence, suggesting that TFIID was functionally dispensable for PGK1 transcription at least in the SPT3 strain. Furthermore, transcription from the TATA box-containing PGK1 promoter was slightly reduced in the taf1 strain lacking TAND (taf1-ΔTAND) upon temperature shift from 25 to 37 °C, with restoration to normal levels within 2 h, in an Spt3-dependent manner. Interestingly, when SPT3 was reintroduced into the spt3Δ TAF1, spt3Δ taf1-N568Δ or spt3Δ taf1-ΔTAND strain, TATA box-dependent transcription from this promoter was largely restored, but TFIID independence in transcription was not restored, especially from the TATA-less promoter, and transient TAND/Spt3-dependent fluctuations of transcription after the temperature shift were also not recapitulated. Collectively, these observations suggest that Spt3 has multiple functions in PGK1 transcription, some of which may be intimately connected to Taf1 function and may therefore become unrestorable when the TFIID and SAGA functions are simultaneously compromised. [ABSTRACT FROM AUTHOR]
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- 2020
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20. Tanshinone and salvianolic acid biosynthesis are regulated by SmMYB98 in Salvia miltiorrhiza hairy roots.
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Hao, Xiaolong, Pu, Zhongqiang, Cao, Gang, You, Dawei, Zhou, Yang, Deng, Changping, Shi, Min, Nile, Shivraj Hariram, Wang, Yao, Zhou, Wei, and Kai, Guoyin
- Abstract
• SmMYB98 was predominantly expressed in the lateral roots of Salvia miltiorrhiza. • Tanshinones and salvianolic acids were improved in the SmMYB98-OE hairy roots. • Tanshinone and salvianolic acid contents in SmMYB98-KO lines were reduced. • SmMYB98 regulates the expression of tanshinones and salvianolic acids biosynthetic genes. • SmMYB98 negatively regulates the biosynthesis of gibberellins in S. miltiorrhiza. Salvia miltiorrhiza Bunge is an herb rich in bioactive tanshinone and salvianolic acid compounds. It is primarily used as an effective medicine for treating cardiovascular and cerebrovascular diseases. Liposoluble tanshinones and water-soluble phenolic acids are a series of terpenoids and phenolic compounds, respectively. However, the regulation mechanism for the simultaneous promotion of tanshinone and salvianolic acid biosynthesis remains unclear. This study identified a R2R3-MYB subgroup 20 transcription factor (TF), SmMYB98 , which was predominantly expressed in S. miltiorrhiza lateral roots. The accumulation of major bioactive metabolites, tanshinones, and salvianolic acids, was improved in SmMYB98 overexpression (OE) hairy root lines, but reduced in SmMYB98 knockout (KO) lines. The qRT-PCR analysis revealed that the transcriptional expression levels of tanshinone and salvianolic acid biosynthesis genes were upregulated by SmMYB98-OE and downregulated by SmMYB98-KO. Dual-Luciferase (Dual-LUC) assays demonstrated that SmMYB98 significantly activated the transcription of SmGGPPS1 , SmPAL1 , and SmRAS1. These results suggest that SmMYB98-OE can promote tanshinone and salvianolic acid production. The present findings illustrate the exploitation of R2R3-MYB in terpenoid and phenolic biosynthesis, as well as provide a feasible strategy for improving tanshinone and salvianolic acid contents by MYB proteins in S. miltiorrhiza. [ABSTRACT FROM AUTHOR]
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- 2020
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21. The transcriptional regulator PRDM12 is critical for Pomc expression in the mouse hypothalamus and controlling food intake, adiposity, and body weight.
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Hael, Clara E., Rojo, Daniela, Orquera, Daniela P., Low, Malcolm J., and Rubinstein, Marcelo
- Abstract
Regulation of food intake and energy balance depends on a group of hypothalamic neurons that release anorexigenic melanocortins encoded by the Pomc gene. Although the physiological importance of central melanocortins is well appreciated, the genetic program that defines the functional identity of melanocortin neurons and assures high levels of hypothalamic Pomc expression is only beginning to be understood. This study assessed whether the transcriptional regulator PRDM12, identified as a highly expressed gene in adult mouse POMC neurons, plays an important role in the identity and function of melanocortin neurons. We first determined the cellular distribution of PRDM12 in the developing hypothalamus. Then we studied mutant mice with constitutively inactivated Prdm12 to evaluate possible changes in hypothalamic Pomc expression. In addition, we characterized conditional mutant mice specifically lacking Prdm12 in ISL1-positive or POMC neurons during development. Finally, we measured food intake, body weight progression up to 16 weeks of age, adiposity, and glucose tolerance in adult mice lacking Prdm12 selectively from POMC neurons. PRDM12 co-expressed with POMC in mouse hypothalamic neurons from early development to adulthood. Mice lacking Prdm12 displayed greatly reduced Pomc expression in the developing hypothalamus. Selective ablation of Prdm12 from ISL1 neurons prevented hypothalamic Pomc expression. The conditional ablation of Prdm12 limited to POMC neurons greatly reduced Pomc expression in the developing hypothalamus and in adult mice led to increased food intake, adiposity, and obesity. Altogether, our results demonstrate that PRDM12 plays an essential role in the early establishment of hypothalamic melanocortin neuron identity and the maintenance of high expression levels of Pomc. Its absence in adult mice greatly impairs Pomc expression and leads to increased food intake, adiposity, and obesity. • PRDM12 co-expresses with POMC in the developing hypothalamus and determines the establishment of melanocortin neuron identity. • The onset of Pomc expression in the presumptive arcuate nucleus is impaired in mutant mice lacking Prdm12. • PRDM12 promotes the transcriptional activation of Pomc in a cell-autonomous manner. • The lack of PRDM12 from POMC neurons leads to increased food intake, adiposity and obesity in adult mice. [ABSTRACT FROM AUTHOR]
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- 2020
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22. HSF1 promotes the viability of islet β-cells via upregulating SIRPα expression.
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ZHANG, H.-M., YANG, M., ZHANG, X.-Y., TANG, Y., WU, J.-L., and HUANG, J.
- Abstract
OBJECTIVE: Increasing evidence has shown that HSF1 is involved in glycemia regulation, and SIRPα plays a pivotal role in islet β-cell viability. However, it is still unknown whether SIRPα is associated with HSF1 in regulating the cell viability and cell death of islet β-cells. MATERIALS AND METHODS: Western blot and qPCR were applied to determine protein and mRNA levels of HSF1 and SIRPα. Cell viability and death were investigated by cell counting kit-8 and trypan blue exclusion assay. Meanwhile, cell apoptosis was analyzed by detecting caspase3 activity. Moreover, luciferase reporter assay was applied to explore the mechanism by which HSF1 transcriptionally upregulated SIRPα expression. RESULTS: O ur s tudy r eveals t hat H SF1 e xpression was lower in islets from T1DM compared to normal mice. We found that overexpression of HSF1 decreased the apoptosis of islet β-cell lines. Moreover, we demonstrated that overexpression of HSF1 decreased the apoptosis of islet β-cells through increasing the expression of SIRPα. In terms of mechanism, luciferase reporter assays showed that HSF1 upregulated SIRPα expression by activating its gene promoter region. The binding site (-1809 to -1795) was required for HSF1-induced increase of SIRPα gene promoter activity. CONCLUSIONS: These results indicate that the low expression of HSF1/SIRPα may be one of the mechanisms of islet β-cell death and targeting HSF1/SIRPα may be a novel strategy for the treatment of T1DM. [ABSTRACT FROM AUTHOR]
- Published
- 2020
23. PXR: a center of transcriptional regulation in cancer.
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Xing, Yaqi, Yan, Jiong, and Niu, Yongdong
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PREGNANE X receptor ,REGULATOR genes ,CANCER chemotherapy ,OXIDATIVE stress ,CANCER - Abstract
Pregnane X receptor (PXR, NR1I2) is a prototypical member of the nuclear receptor superfamily. PXR can be activated by both endobiotics and xenobiotics. As a key xenobiotic receptor, the cellular function of PXR is mostly exerted by its binding to the regulatory gene sequences in a ligand-dependent manner. Classical downstream target genes of PXR participate in xenobiotic responses, such as detoxification, metabolism and inflammation. Emerging evidence also implicates PXR signaling in the processes of apoptosis, cell cycle arrest, proliferation, angiogenesis and oxidative stress, which are closely related to cancer. Here, we discussed, in addition to the characterization of PXR per se , the biological function and regulatory mechanism of PXR signaling in cancer, and its potential for the targeted prevention and therapeutics. PXR and its target genes could constitute complex cellular circuits to influence initiation, promotion, progression and chemotherapy outcome of cancer by participating in various physiological and pathological progressions. Image 1 [ABSTRACT FROM AUTHOR]
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- 2020
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24. A Common Tag Nucleotide Variant in Promoter Increases Risk for Hypertension via Enhanced Interactions With CREB (Cyclic AMP Response Element-Binding Protein) Transcription Factor.
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Subramanian, Lakshmi, Maghajothi, Sakthisree, Singh, Mrityunjay, Kesh, Kousik, Kalyani, Ananthamohan, Sharma, Saurabh, Khullar, Madhu, Victor, Suma M., Swarnakar, Snehasikta, Asthana, Shailendra, Mullasari, Ajit S., and Mahapatra, Nitish R.
- Abstract
MMP (matrix metalloproteinase)-7-a potent extracellular matrix degrading enzyme-is emerging as a new regulator of cardiovascular diseases. However, potential contributions of MMP7 genetic variations to hypertension remain unknown. In this study, we probed for the association of a tag single-nucleotide polymorphism in the MMP7 promoter (-181A/G; rs11568818) with hypertension in an urban South Indian population (n=1501). The heterozygous AG genotype significantly increased risk for hypertension as compared with the wild-type AA genotype (odds ratio, 1.60 [95% CI, 1.25-2.06]; P=2.4×10-4); AG genotype carriers also displayed significantly higher diastolic blood pressure and mean arterial pressure than wild-type AA individuals. The study was replicated in a North Indian population (n=949) (odds ratio, 1.52 [95% CI, 1.11-2.09]; P=0.01). Transient transfection experiments using MMP7 promoter-luciferase reporter constructs revealed that the variant -181G allele conferred greater promoter activity than the -181A allele. Computational prediction and structure-based conformational and molecular dynamics simulation studies suggested higher binding affinity for the CREB (cyclic AMP response element-binding protein) to the -181G promoter. In corroboration, overexpression/downregulation of CREB and chromatin immunoprecipitation experiments provided convincing evidence for stronger binding of CREB with the -181G promoter. The -181G promoter also displayed enhanced responses to hypoxia and epinephrine treatment. The higher promoter activity of -181G allele translated to increased MMP7 protein level, and MMP7-181AG heterozygous individuals displayed elevated plasma MMP7 levels, which positively correlated with blood pressure. In conclusion, the MMP7 A-181G promoter polymorphism increased MMP7 expression under pathophysiological conditions (hypoxic stress and catecholamine excess) via increased interactions with CREB and enhanced the risk for hypertension in its carriers. [ABSTRACT FROM AUTHOR]
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- 2019
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25. The role of Ca2+-signaling in the regulation of epigenetic mechanisms.
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Hernández-Oliveras, Andrés and Zarain-Herzberg, Angel
- Abstract
• Epigenetics and Ca
2+ signaling are mechanisms involved in multiple cellular functions. • Ca2+ -activated transcription factors regulate chromatin-remodeling complexes. • Ca2+ -activated proteins modulate the activity of epigenetic mechanisms. • Ca2+ -induced epigenetic mechanisms regulate the expression of Ca2+ signaling genes. Epigenetic mechanisms regulate multiple cell functions like gene expression and chromatin conformation and stability, and its misregulation could lead to several diseases including cancer. Epigenetic drugs are currently under investigation in a broad range of diseases, but the cellular processes involved in regulating epigenetic mechanisms are not fully understood. Calcium (Ca2+ ) signaling regulates several cellular mechanisms such as proliferation, gene expression, and metabolism, among others. Moreover, Ca2+ signaling is also involved in diseases such as neurological disorders, cardiac, and cancer. Evidence indicates that Ca2+ signaling and epigenetics are involved in the same cellular functions, which suggests a possible interplay between both mechanisms. Ca2+ -activated transcription factors regulate the recruitment of chromatin remodeling complexes into their target genes, and Ca2+ -sensing proteins modulate their activity and intracellular localization. Thus, Ca2+ signaling is an important regulator of epigenetic mechanisms. Moreover, Ca2+ signaling activates epigenetic mechanisms that in turn regulate genes involved in Ca2+ signaling, suggesting possible feedback between both mechanisms. The understanding of how epigenetics are regulated could lead to developing better therapeutical approaches. [Display omitted] [ABSTRACT FROM AUTHOR]- Published
- 2024
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26. Xenopus laevis FGF16 activates the expression of genes coding for the transcription factors Sp5 and Sp5l.
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ELSY, MICHAEL, ROWBOTHAM, ABIGAIL, LORD, HANNAH, ISAACS, HARRY V., and POWNALL, MARY E.
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XENOPUS laevis ,MESODERM ,TRANSCRIPTION factors ,FIBROBLAST growth factors ,GENETIC code ,EMBRYOLOGY - Abstract
Fibroblast growth factors (FGFs) comprise a family of signalling molecules with essential roles in early embryonic development across animal species. The role of FGFs in mesoderm formation and patterning in Xenopus has been particularly well studied. However, little is known about FGF16 in Xenopus. Using in situ hybridisation, we uncover the expression pattern of FGF16 during early Xenopus laevis development, which has not been previously described. We show that the zygotic expression of FGF16 is activated in the mesoderm of the early gastrula as a ring around the blastopore, with its first accumulation at the dorsal side of the embryo. Later, FGF16 expression is found in the otic vesicle, the branchial arches and the anterior pituitary, as well as in the chordal neural hinge region of the tailbud. In addition, we show that FGF16 can activate the MAPK pathway and expression of sp5 and sp5l. Like FGF16, sp5 is expressed in the otic vesicle and the branchial arches, with all three of these genes being expressed in the tailbud. These data provide evidence that FGF16 is present in the early mesoderm and can activate the expression of developmentally important transcription factors. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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27. HSP70 induces liver X receptor pathway activation and cholesterol reduction in vitro and in vivo.
- Author
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Gungor, Burcin, Vanharanta, Lauri, Hölttä-Vuori, Maarit, Pirhonen, Juho, Petersen, Nikolaj H.T., Gramolelli, Silvia, Ojala, Päivi M., Kirkegaard, Thomas, and Ikonen, Elina
- Abstract
Heat Shock Proteins (HSPs) maintain cellular homeostasis under stress. HSP70 represents a major stress-inducible family member and has been identified as a druggable target in inherited cholesterol-sphingolipid storage diseases. We investigated if HSP70 modulates cholesterol accumulation in more common conditions related to atherogenesis. We studied the effects of recombinant HSP70 in cholesterol-laden primary macrophages from human blood donors and pharmacological HSP70 upregulation in high-cholesterol diet fed zebrafish. Recombinant HSP70 facilitated cholesterol removal from primary human macrophage foam cells. RNA sequencing revealed that HSP70 induced a robust transcriptional re-programming, including upregulation of key targets of liver X receptors (LXR), master regulators of whole-body cholesterol removal. Mechanistically, HSP70 interacted with the macrophage LXRalpha promoter, increased LXRalpha and its target mRNAs, and led to elevated levels of key proteins facilitating cholesterol efflux, including ATP-binding cassette transporters A1 and G1. Pharmacological augmentation of endogenous HSP70 in high-cholesterol diet fed zebrafish activated LXR and its target mRNAs and reduced cholesterol storage at the whole organism level. These data demonstrate that HSP70 exerts a cholesterol lowering effect in primary human cells and animals and uncover a nuclear action of HSP70 in mediating cross-talk between HSP and LXR transcriptional regulation. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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28. Regulation of pH by Carbonic Anhydrase 9 Mediates Survival of Pancreatic Cancer Cells With Activated KRAS in Response to Hypoxia.
- Author
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McDonald, Paul C., Chafe, Shawn C., Brown, Wells S., Saberi, Saeed, Swayampakula, Mridula, Venkateswaran, Geetha, Nemirovsky, Oksana, Gillespie, Jordan A., Karasinska, Joanna M., Kalloger, Steve E., Supuran, Claudiu T., Schaeffer, David F., Bashashati, Ali, Shah, Sohrab P., Topham, James T., Yapp, Donald T., Li, Jinyang, Renouf, Daniel J., Stanger, Ben Z., and Dedhar, Shoukat
- Abstract
Most pancreatic ductal adenocarcinomas (PDACs) express an activated form of KRAS, become hypoxic and dysplastic, and are refractory to chemo and radiation therapies. To survive in the hypoxic environment, PDAC cells upregulate enzymes and transporters involved in pH regulation, including the extracellular facing carbonic anhydrase 9 (CA9). We evaluated the effect of blocking CA9, in combination with administration of gemcitabine, in mouse models of pancreatic cancer. We knocked down expression of KRAS in human (PK-8 and PK-1) PDAC cells with small hairpin RNAs. Human and mouse (Kras
G12D / Pdx1-Cre / Tp53 / RosaYFP ) PDAC cells were incubated with inhibitors of MEK (trametinib) or extracellular signal-regulated kinase (ERK), and some cells were cultured under hypoxic conditions. We measured levels and stability of the hypoxia-inducible factor 1 subunit alpha (HIF1A), endothelial PAS domain 1 protein (EPAS1, also called HIF2A), CA9, solute carrier family 16 member 4 (SLC16A4, also called MCT4), and SLC2A1 (also called GLUT1) by immunoblot analyses. We analyzed intracellular pH (pHi) and extracellular metabolic flux. We knocked down expression of CA9 in PDAC cells, or inhibited CA9 with SLC-0111, incubated them with gemcitabine, and assessed pHi, metabolic flux, and cytotoxicity under normoxic and hypoxic conditions. Cells were also injected into either immune-compromised or immune-competent mice and growth of xenograft tumors was assessed. Tumor fragments derived from patients with PDAC were surgically ligated to the pancreas of mice and the growth of tumors was assessed. We performed tissue microarray analyses of 205 human PDAC samples to measure levels of CA9 and associated expression of genes that regulate hypoxia with outcomes of patients using the Cancer Genome Atlas database. Under hypoxic conditions, PDAC cells had increased levels of HIF1A and HIF2A, upregulated expression of CA9, and activated glycolysis. Knockdown of KRAS in PDAC cells, or incubation with trametinib, reduced the posttranscriptional stabilization of HIF1A and HIF2A, upregulation of CA9, pHi, and glycolysis in response to hypoxia. CA9 was expressed by 66% of PDAC samples analyzed; high expression of genes associated with metabolic adaptation to hypoxia, including CA9, correlated with significantly reduced survival times of patients. Knockdown or pharmacologic inhibition of CA9 in PDAC cells significantly reduced pHi in cells under hypoxic conditions, decreased gemcitabine-induced glycolysis, and increased their sensitivity to gemcitabine. PDAC cells with knockdown of CA9 formed smaller xenograft tumors in mice, and injection of gemcitabine inhibited tumor growth and significantly increased survival times of mice. In mice with xenograft tumors grown from human PDAC cells, oral administration of SLC-0111 and injection of gemcitabine increased intratumor acidosis and increased cell death. These tumors, and tumors grown from PDAC patient-derived tumor fragments, grew more slowly than xenograft tumors in mice given control agents, resulting in longer survival times. In KrasG12D / Pdx1-Cre / Tp53 / RosaYFP genetically modified mice, oral administration of SLC-0111 and injection of gemcitabine reduced numbers of B cells in tumors. In response to hypoxia, PDAC cells that express activated KRAS increase expression of CA9, via stabilization of HIF1A and HIF2A, to regulate pH and glycolysis. Disruption of this pathway slows growth of PDAC xenograft tumors in mice and might be developed for treatment of pancreatic cancer. [ABSTRACT FROM AUTHOR]- Published
- 2019
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29. The chromatin remodeling protein BRG1 links ELOVL3 trans-activation to prostate cancer metastasis.
- Author
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Yang, Yuyu, Liu, Li, Li, Min, Cheng, Xian, Fang, Mingming, Zeng, Qingqi, and Xu, Yong
- Abstract
Prostate cancer malignancies are intimately correlated with deregulated fatty acid metabolism. The underlying epigenetic mechanism is not fully understood. In the present study we investigated the mechanism whereby the chromatin remodeling protein BRG1 regulates the transcription of long-chain fatty acid elongase 3 (Elovl3) in prostate cancer cells. We report that in response to pro-metastatic cues (androgen and TGF-β) BRG1 expression was up-regulated along with Elvol3 in prostate cancer cells. BRG1 over-expression potentiated whereas BRG1 knockdown attenuated prostate cancer cell migration and invasion. Coincidently, Elovl3 was up-regulated following BRG1 over-expression and down-regulated after BRG1 knockdown in prostate cancer cells. Further analysis revealed that BRG1 interacted with and was recruited by retinoic acid receptor-related orphan receptor (RORγ) to the Elovl3 promoter to activate transcription. Chromatin immunoprecipitation (ChIP) profiling demonstrated that BRG1 interacted with histone acetyltransferase p300 to activate Elovl3 transcription. Depletion of p300 by siRNA or inhibition of p300 by curcumin attenuated Elovl3 trans-activation in prostate cancer cells. Together, our data identify a novel epigenetic pathway that links Elovl3 transcription to prostate cancer cell migration and invasion. • BRG1 promotes migration and invasion of prostate cancer cells. • BRG1 is essential for ELOVL3 trans-activation by TGF/DHT in prostate cancer cells. • BRG1 interacts with RORγ to activate ELOVL3 transcription. • BRG1 recruits p300 to activate ELOVL3 transcription. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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30. Small molecules and cell differentiation in Dictyostelium discoideum.
- Author
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TSUYOSHI ARAKI and TAMAO SAITO
- Subjects
SMALL molecules ,DICTYOSTELIUM discoideum ,CELL differentiation ,POLYKETIDES ,METABOLITES ,MULTICELLULAR organisms - Abstract
Dictyostelium is a microorganism found in soils that are known as the battle fields of chemical warfare. Genome analysis of Dictyostelium revealed that it has great potential for the production of small molecules, including secondary metabolites such as polyketides and terpenes. Polyketides are a large family of secondary metabolites which have a variety of structures. In accordance with their structural variety, polyketides have a plethora of biological activities, including antimicrobial, antifungal, and antitumor activities. Unsurprisingly, they have exceptional medical importance. Polyketides in nature work as protective compounds and/or function in pheromonal communication. Terpenes belong to another family of structurally diverse secondary metabolites which play roles in ecological interactions, including defence against predators and formation of mutually beneficial alliance with other organisms. Polyketides and terpenes work as intra- or inter-species signalling compounds, i.e. they play the role of a chemical language. However, in Dictyostelium, they work as paracrine signalling compounds which control the organism's multicellular morphogenesis. This review is primarily focused on the small molecules that regulate pattern formation in the slug stage of the organism and their biosynthetic pathways. Current in vivo understandings of polyketide DIF-1 induced cell differentiation and DIF-1-dependent/independent pathways are also discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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31. A non-autonomous role of MKL1 in the activation of hepatic stellate cells.
- Author
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Li, Zilong, Li, Ping, Lu, Yunjie, Sun, Donglin, Zhang, Xiaoying, and Xu, Yong
- Abstract
Although hepatic stellate cells (HSC) represent the major source of fibrogenesis in the liver under various pathological conditions, other cell types including hepatic parenchymal cells (hepatocytes) also contribute to HSC activation and hence liver fibrosis. The underlying mechanism, however, is poorly defined. Here we report that hepatocytes exposed to high concentrations of glucose (HG) emit a pro-fibrogenic cue as evidenced by the observation that primary HSCs cultured in conditioned media (CM) collected from hepatocytes exposed to HG up-regulated the production of extracellular matrix (ECM) proteins compared to CM collected from hepatocytes exposed to low glucose. We further identified the pro-fibrogenic cue from hepatocytes to be connective tissue growth factor (CTGF) because either depletion of endogenous CTGF in hepatocytes with siRNA or the addition of a CTGF-specific neutralizing antibody to the CM blunted the pro-fibrogenic effect elicit by HG treatment. Of interest, we discovered that genetic ablation or pharmaceutical inhibition of the transcriptional modulator MKL1 in hepatocytes also abrogated the HG-induced pro-fibrogenic effects. Mechanistically, MKL1 interacted with AP-1 and SMAD3 to trans-activate CTGF in hepatocytes in response to HG treatment. In conclusion, our data suggest that MKL1 contribute to HSC activation in a non-autonomous fashion by promoting CTGF transcription in hepatocytes. • A pro-fibrogenic cue is emitted from HG-treated hepatocyte. • CTGF is released from HG-treated hepatocyte to promote HSC activation. • MKL1 activates CTGF transcription in HG-treated heaptocyte. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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32. The chromatin remodeling protein BRM regulates the transcription of tight junction proteins: Implication in breast cancer metastasis.
- Author
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Yang, Yuyu, Liu, Li, Fang, Mingming, Bai, Hui, and Xu, Yong
- Abstract
Abstract Claudins are a group of cell tight junction proteins that play versatile roles in cancer biology. Recent studies have correlated down-regulation of Claudins with augmented breast cancer malignancy and poor prognosis. The mechanism underlying repression of Claudin transcription in breast cancer cells is not well understood. Here we report that expression levels of Brahma (BRM) were down-regulated in triple negative breast cancer cells (MDA-231) compared to the less malignant MCF-7 cells and in high-grade human breast cancer specimens compared to low-grade ones. TGF-β treatment in MCF-7 cells repressed BRM transcription likely through targeting C/EBPβ. BRM over-expression suppressed whereas BRM knockdown promoted TGF-β induced migration and invasion of MCF-7 cells. BRM down-regulation was accompanied by the loss of a panel of Claudins in breast cancer cells. BRM directly bound to the promoter region of Claudin genes via interacting with Sp1 and activated transcription by modulating histone modifications. Together, our data have identified a novel epigenetic pathway that links Claudin transcription to breast cancer metastasis. Highlights • BRM expression correlates with Claudin expression in breast cancer cells. • TGF-β down-regulates C/EBPβ to repress BRM transcription. • BRM suppresses breast cancer cell migration and invasion. • Sp1 interacts with and recruits BRM to activate Claudin transcription. • BRM interacts with PCAF and p300 to activate Claudin transcription. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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33. Sweet sorghum (Sorghum bicolor L.) SbSTOP1 activates the transcription of a β-1,3-glucanase gene to reduce callose deposition under Al toxicity: A novel pathway for Al tolerance in plants.
- Author
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Gao, Jie, Yan, Siqi, Yu, Haiye, Zhan, Meiqi, Guan, Kexing, Wang, Yanqiu, and Yang, Zhenming
- Subjects
SORGHUM ,SORGO ,SORGHUM farming ,ACID soils ,AGRICULTURAL productivity ,PLANT roots - Abstract
Aluminum (Al) toxicity is a primary limiting factor for crop production in acid soils. Callose deposition, an early indicator and likely a contributor to Al toxicity, is induced rapidly in plant roots under Al stress. SbGlu1, encoding a β-1,3-glucanase for callose degradation, showed important roles in sorghum Al resistance, yet its regulatory mechanisms remain unclear. The STOP1 transcription factors mediate Al signal transduction in various plants. Here, we identified their homolog in sweet sorghum, SbSTOP1, transcriptionally activated the expression of SbGlu1. Moreover, the DNA sequence recognized by SbSTOP1 on the promoter of SbGlu1 lacked the reported cis-acting element. Complementation lines of Atstop1 with SbSTOP1 revealed enhanced transcription levels of SbGlu1 homologous gene and reduced callose accumulation in Arabidopsis. These results indicate, for the first time, that SbSTOP1 is involved in the modulation of callose deposition under Al stress via transcriptional regulation of a β-1,3-glucanase gene. [ABSTRACT FROM AUTHOR]
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- 2019
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34. 甘蓝型油菜皖油20 号种子不同部位油脂合成的转录调控分析.
- Author
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张宇婷, 鲁少平, 金 诚, and 郭 亮
- Abstract
Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2019
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35. Identification of the full 26 cytochrome P450 (CYP) genes and analysis of their expression in response to benzo[α]pyrene in the marine rotifer Brachionus rotundiformis.
- Author
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Han, Jeonghoon, Park, Jun Chul, Hagiwara, Atsushi, Park, Heum Gi, and Lee, Jae-Seong
- Subjects
XENOBIOTICS ,CYTOCHROME P-450 ,GENE expression ,ARYL hydrocarbon receptors ,ORGANISMS ,BRACHIONUS - Abstract
Abstract Cytochrome P450s (CYPs) are a large gene superfamily that are found in all living organisms. CYPs have a key role in detoxification of xenobiotics and endogenous chemicals. Although aquatic invertebrate CYPs and their detoxification mechanisms have been reported, little is known about interspecific comparison of CYPs and their detoxification mechanism in the rotifer Brachionus spp. The aim of this study was to identify the entire CYP s in the rotifer Brachionus rotundiformis (B. rotundiformis) and compare B. rotundiformis -CYPs to the previously reported CYPs in other model Brachionus spp. (B. koreanus , B. plicatilis , and B. calyciflorus). To validate the model, the rotifer, specifically Brachionus rotundiformis was exposed to various concentrations of B[α]P, which is widely used PAH xenobiotic, and analyzed gene expression in response to B[α]P. Here, in silico analysis results showed the total of 26 CYP s from the rotifer B. rotundiformis. Based on the phylogenetic analysis, the 26 B. rotundiformis -CYPs were separated into five different clans: 2, 3, 4, mitochondrial, and 46 clans in comparison to three rotifers species, B. koreanus , B. plicatilis , and B. calyciflorus. To understand the detoxification mechanisms of 26 B. rotundiformis -CYPs, we investigated transcriptional expression of 26 CYP s and found that five CYP s (CYP3045A2 , CYP3045B4 , CYP3045C10 , CYP3049A5 , and CYP3049E8) were significantly increased (P < 0.05) in response to 10 and 100 μg B[α]P. In addition, we identified the aryl hydrocarbon receptor (AhR) and aryl hydrocarbon receptor nuclear translocator (ARNT) and observed slight up-regulation of B. rotundiformis - AhR and - ARNT , indicating that these CYPs are likely associated with detoxification mechanism and could be used as potential molecular biomarkers of B[α]P in B. rotundiformis. Overall, this study will be helpful for expanding our knowledge of invertebrate CYPs on detoxification mechanisms associated with AhR signaling pathway in rotifers. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]
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- 2019
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36. Class II transactivator (CIITA) mediates IFN-γ induced eNOS repression by enlisting SUV39H1.
- Author
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Weng, Xinyu, Zhang, Yuanyuan, Li, Zilong, Yu, Liming, Xu, Feng, Fang, Mingming, Hou, Lei, Ge, Junbo, and Xu, Yong
- Abstract
Abstract Endothelial nitric oxide synthase (eNOS), selectively expressed in vascular endothelial cells, plays important roles in a range of biological and pathological processes. eNOS levels can be altered by extrinsic and intrinsic cues at the transcriptional level. Here we examined the epigenetic mechanism whereby the pro-inflammatory cytokine interferon gamma (IFN-γ) represses eNOS transcription. In response to IFN-γ treatment, there was a simultaneous down-regulation of eNOS expression and up-regulation of class II trans-activator (CIITA). Over-expression of CIITA directly repressed eNOS promoter while CIITA knockdown attenuated IFN-γ induced eNOS repression. Chromatin immunoprecipitation (ChIP) assay revealed that IFN-γ stimulation promoted CIITA occupancy on the proximal eNOS (−430/−168). Coincidently, CIITA recruitment to the eNOS promoter was paralleled by the disappearance of trimethylated histone H3K4 (H3K4Me3) and the enrichment of trimethylated H3K9 (H3K9Me3) with no significant changes in the levels of trimethylated H3K27 (H3K27Me3) or trimethylated H4K20 (H4K20Me3). In accordance, CIITA depletion was associated with the normalization of H3K4Me3 and H3K9Me3 on the eNOS promoter. Mechanistically, CIITA interacted with and enlisted the histone H3K9 trimethyltransferase SUV39H1 to the eNOS promoter to repress transcription. IFN-γ treatment augmented SUV39H1 expression and promoted SUV39H1 recruitment to the eNOS promoter in endothelial cells. Silencing of SUV39H1 abrogated eNOS repression by IFN-γ by erasing H3K9Me3 from the eNOS promoter. In conclusion, our data reveal a novel role for CIITA in endothelial cells and present SUV39H1 as a druggable target in the intervention of endothelial dysfunction. Highlights • IFN-γ induced CIITA up-regulation and eNOS down-regulation in endothelial cells. • CIITA mediates IFN-γ induced eNOS trans-repression. • CIITA interacts with and recruits SUV39H1 to the eNOS promoter. • SUV39H1 is essential for IFN-γ induced eNOS trans-repression. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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37. Regulation of glucose uptake and inflammation markers by FOXO1 and FOXO3 in skeletal muscle.
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Lundell, Leonidas S., Massart, Julie, Altıntaş, Ali, Krook, Anna, and Zierath, Juleen R.
- Abstract
Abstract Objective Forkhead box class O (FOXO) transcription factors regulate whole body energy metabolism, skeletal muscle mass, and substrate switching. FOXO1 and FOXO3 are highly abundant transcription factors, but their precise role in skeletal muscle metabolism has not been fully elucidated. Methods To elucidate the role of FOXO in skeletal muscle, dominant negative (dn) constructs for FOXO1 (FOXO1dn) or FOXO3 (FOXO3dn) were transfected by electroporation into mouse tibialis anterior muscle and glucose uptake, signal transduction, and gene expression profiles were assessed after an oral glucose tolerance test. Results were compared against contralateral control transfected muscle. Results FOXO1dn and FOXO3dn attenuated glucose uptake (35%, p < 0.01 and 20%, p < 0.05), GLUT4 protein (40%, p < 0.05 and 10%, p < 0.05), and subunits of the oxidative phosphorylation cascade. Intramuscular glycogen content was decreased (20%, p < 0.05) by FOXO3dn, but not FOXO1dn. Transcriptomic analysis revealed major pathways affected by FOXO1dn or FOXO3dn revolve around metabolism and inflammation. FOXO1dn increased Akt protein (140%, p < 0.001), p -Akt
Ser473 (720%, p < 0.05) and p-AktThr308 (570%, p < 0.01), whereas FOXO3dn was without effect. FOXO1dn and FOXO3dn increased mTOR protein content (170% and 190%, p < 0.05), and p-p70S6KThr389 (420%, p < 0.01 and 300%, p < 0.01), while p-mTORSer2448 (500%, p < 0.01), was only increased by FOXO1dn. Chemokines and immune cell markers were robustly upregulated in skeletal muscle following the FOXOdn transfections, but not after control transfection. Conclusions FOXO1 and FOXO3 regulate glucose metabolism and markers of inflammation in skeletal muscle, implicating transcriptional control governing " immunometabolic " dynamics. Graphical abstract FOXO1 or FOXO3 dominant negative (FOXOdn) transfection of tibialis anterior skeletal muscle decreased glucose uptake and protein abundance of GLUT4 and oxidative phosphorylation enzymes. Inflammatory signaling was upregulated by FOXOdn transfection, indicating that FOXO transcriptional activity regulates energy metabolism and inflammatory signaling in skeletal muscle. Image 1 Highlights • FOXO1 and FOXO3 transcriptional activity regulates glucose uptake and inflammation. • Inhibiting FOXO1 transcriptional activity affects more genes compared to FOXO3. • Inhibiting FOXO1 and FOXO3 leads to similar pathway enrichment. [ABSTRACT FROM AUTHOR]- Published
- 2019
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38. Transcriptional regulation of virulence factors Spa and ClfB by the SpoVG-Rot cascade in Staphylococcus aureus.
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Zhu, Qing, Wen, Wen, Wang, Wanying, and Sun, Baolin
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STAPHYLOCOCCUS aureus ,VIRULENCE of bacteria ,MICROBIAL virulence genetics ,GENETIC regulation ,BACTERIAL proteins - Abstract
Abstract Staphylococcus aureus can produce numerous surface proteins involved in the adhesion and internalization of host cells, immune evasion, and inflammation initiation. Among these surface proteins, the microbial surface components recognizing adhesive matrix molecules contain many crucial cell wall-anchored virulence factors. The Sar-family regulatory protein Rot has been reported to regulate many important extracellular virulence factors at the transcriptional level, including Spa and clumping factor B. SpoVG, a global regulator in S. aureus , is known to control the expression of numerous genes. Here, we demonstrate that SpoVG can positively regulate the transcription of rot by directly binding to its promoter. SpoVG can also positively regulate the transcription of spa and clfB through direct-binding to their promoters and in a Rot-mediated manner. Furthermore, SpoVG can positively modulate the human fibrinogen-binding ability of S. aureus. In addition, phosphorylation of SpoVG by the serine/threonine kinase, Stk1, can positively regulate its binding to the promoters of rot , spa , and clfB. The human cell infection assay showed that the adhesion and internalization abilities were reduced in the spoVG mutant strain in comparison to those in the wild-type strain. Collectively, our data reveal a SpoVG-Rot regulatory cascade and novel molecular mechanisms in the virulence control in S. aureus. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
39. Angiotensin II induced CSF1 transcription is mediated by a crosstalk between different epigenetic factors in vascular endothelial cells.
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Shao, Jing, Weng, Xinyu, Zhuo, Lili, Yu, Liming, Li, Zilong, Shen, Kaiping, Xu, Wenping, Fang, Mingming, and Xu, Yong
- Abstract
Abstract Endothelium-derived colony stimulating factor (CSF1) plays a key role in a range of human pathologies. Angiotensin II (Ang II) has been documented to stimulate CSF1 transcription although the underlying epigenetic mechanism remains unclear. Here we report that induction of CSF1 transcription by Ang II in vascular endothelial cells paralleled alterations of signature histone modifications surrounding the CSF1 promoter. Specifically, ChIP assays indicated that there was a simultaneous up-regulation of both acetylated H3 and trimethylated H3K4, indicative of transcriptional activation, and down-regulation of dimethyl H3K9, implicated in transcriptional repression, surrounding the proximal CSF1 promoter. Further analysis revealed that silencing of brahma related gene 1 (BRG1), a chromatin remodeling protein, abrogated CSF1 induction by Ang II. In the meantime, BRG1 silencing erased H3 acetylation and H3K4 trimethylation and restored H3K9 dimethylation. Mechanistically, BRG1 interacted with and recruited SET1A, a histone H3K4 methyltransferase, and JMJD1A, a histone H3K9 demethylase, to the CSF1 promoter to alter chromatin structure thereby promoting CSF1 trans-activation in response to Ang II stimulation. Knockdown of either SET1A or JMJD1A blocked CSF1 induction by Ang II. Finally, we demonstrate that the crosstalk between BRG1 and histone modifying enzymes was mediated by the transcription factor AP-1. In conclusion, our data unveil a novel epigenetic mechanism whereby a BRG1-centered complex mediates transcriptional activation of CSF1 by Ang II in vascular endothelial cells. Highlights • Angiotensin induced CSF1 coincides with characteristic histone modifications. • Angiotensin induced CSF1 transcription requires BRG1. • BRG1 interacts with SET1A to activate CSF1 transcription. • BRG1 interacts with JMJD1A to activated CSF1 transcription. • AP-1 recruits BRG1 to activate CSF1 transcription. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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40. Transcriptional regulation of Translocator protein (18 kDa) (TSPO) in microglia requires Pu.1, Ap1 and Sp factors.
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Rashid, Khalid, Geissl, Lea, Wolf, Anne, Karlstetter, Marcus, and Langmann, Thomas
- Abstract
Abstract Mitochondrial Translocator protein (18 kDa) (TSPO) is strongly expressed in reactive microglia and serves as a therapeutic target for alleviation of neuronal degeneration. However, little is known about TSPO's transcriptional regulation in microglia. The aim of this study was to identify genetic elements and transcription factors required for basal and inducible TSPO expression in microglia. Murine Tspo promoter was cloned into the pGL4.10 luciferase vector and functionally characterized in BV-2 cells. Deletion mutagenesis indicated that −845 bases upstream were sufficient to reconstitute near maximal promoter activity in BV-2. Deletion of −593 to −520 sequences, which harbour an Ap1, Ets.2 and Nkx3.1 site which also serves as a non-canonical binding site for Sp1-family transcription factors, led to a dramatic decrease in both basal and LPS induced promoter activity. Further deletion of −168 to −39 sequences, which contains four GC boxes, also led to a significant decrease in promoter activity. Targeted mutations of Ap1, Ets.2, Nkx3.1/Sp1/3/4 and the GC boxes led to significant decreases in promoter activity. ChIP-qPCR revealed that Pu.1, Ap1, Stat3, Sp1, Sp3 and Sp4 bind to the endogenous Tspo promoter. Notably, binding of these factors, with the exception of Stat3, was significantly enhanced upon LPS treatment. RNAi silencing of Pu.1, cJun, cFos, Sp1, Sp3, Sp4 and Stat3 strongly lowered Tspo promoter activity while Ap1 silencing inhibited LPS induced increase in Tspo protein levels. These findings demonstrate that consensus binding sequences for Ap1, Ets.2, distal as well as proximal Sp1/3/4 sites regulate basal and LPS induced Tspo promoter activity in microglia. Highlights • Minimal Tspo promoter extends −845 bases upstream in BV-2 microglia cells. • Promoter region −593 to −520 is crucial for Tspo promoter activity in BV-2 cells. • Ap1, Pu.1, Sp1, Sp3 and Sp4 regulate Tspo promoter activity in BV-2 cells. • Ap1 is a key driver of LPS-induced TSPO protein expression in BV-2 cells. • Differential regulation of the Tspo promoter between BV-2 and ARPE-19 cells [ABSTRACT FROM AUTHOR]
- Published
- 2018
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41. Physiological and transcriptomic analysis of the mangrove species Kandelia obovata in response to flooding stress.
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Liu, Shuangshuang, Yang, Sheng, Liu, Huizi, Hu, Qingdi, Liu, Xing, Wang, Jinwang, Wang, Jiayu, Xin, Wenzhen, and Chen, Qiuxia
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MANGROVE plants ,GENE expression ,TRANSCRIPTOMES ,SUPEROXIDE dismutase ,MYB gene ,PLANT hormones - Abstract
Flooding stress on mangroves is growing continually with rising sea level. In this study, the physiology and transcriptome of the mangrove species Kandelia obovata under flooding stress were analyzed. With increasing inundation time, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), soluble sugar (SS), soluble protein (SP), and proline (Pro) content declined, while peroxidase (POD) and ascorbate peroxidase (APX) activity rose significantly. According to the KEGG pathway enrichment analysis, upregulated differentially expressed genes (DEGs) were enriched in the plant hormone signaling pathway. Furthermore, MYB44 and MYB108 genes from the MYB transcription factor family and RAP2.12 , DREB2B , and ERF4 genes from the AP2/ERF family were up-regulated under flooding conditions. A strong correlation was established between the expression levels of 12 DEGs under flooding stress and RNA sequencing data and was verified by qRT-PCR. These results provide new insights into the molecular mechanism of K. obovata in response to flooding stress. • Flooding stress alters antioxidant and osmoregulatory substances of K. obovata. • The plant hormone signaling pathways function in response to flooding stress. • The MYB and AP2/ERF transcription factor families were linked to flood response. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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42. microRNA-205-5p is a modulator of insulin sensitivity that inhibits FOXO function.
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Langlet, Fanny, Tarbier, Marcel, Haeusler, Rebecca A., Camastra, Stefania, Ferrannini, Eleuterio, Friedländer, Marc R., and Accili, Domenico
- Abstract
Abstract Objectives Hepatic insulin resistance is a hallmark of type 2 diabetes and obesity. Insulin receptor signaling through AKT and FOXO has important metabolic effects that have traditionally been ascribed to regulation of gene expression. However, whether all the metabolic effects of FOXO arise from its regulation of protein-encoding mRNAs is unknown. Methods To address this question, we obtained expression profiles of FOXO-regulated murine hepatic microRNAs (miRNAs) during fasting and refeeding using mice lacking Foxo1, 3a, and 4 in liver (L-Foxo1,3a, 4). Results Out of 439 miRNA analyzed, 175 were differentially expressed in Foxo knockouts. Their functions were associated with insulin, Wnt, Mapk signaling, and aging. Among them, we report a striking increase of miR-205-5p expression in L-Foxo1,3a,4 knockouts, as well as in obese mice. We show that miR-205-5p gain-of-function increases AKT phosphorylation and decreases SHIP2 in primary hepatocytes, resulting in FOXO inhibition. This results in decreased hepatocyte glucose production. Consistent with these observations, miR-205-5p gain-of-function in mice lowered glucose levels and improved pyruvate tolerance. Conclusions These findings reveal a homeostatic miRNA loop regulating insulin signaling, with potential implications for in vivo glucose metabolism. Highlights • A comprehensive analysis of Foxo-dependent miRNA. • miRNAs recapitulate the transcriptional effects of Foxo on insulin signaling. • Foxo regulates miRNA transcription during the fasting/refeeding transition. • miR205 regulates insulin sensitivity through a homeostatic loop with Foxo. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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43. A PDX1-ATF transcriptional complex governs β cell survival during stress.
- Author
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Juliana, Christine A., Yang, Juxiang, Cannon, Corey E., Good, Austin L., Haemmerle, Matthew W., and Stoffers, Doris A.
- Abstract
Abstract Objective Loss of insulin secretion due to failure or death of the insulin secreting β cells is the central cause of diabetes. The cellular response to stress (endoplasmic reticulum (ER), oxidative, inflammatory) is essential to sustain normal β cell function and survival. Pancreatic and duodenal homeobox 1 (PDX1), Activating transcription factor 4 (ATF4), and Activating transcription factor 5 (ATF5) are transcription factors implicated in β cell survival and susceptibility to stress. Our goal was to determine if a PDX1-ATF transcriptional complex or complexes regulate β cell survival in response to stress and to identify direct transcriptional targets. Methods Pdx1 , Atf4 and Atf5 were silenced by viral delivery of gRNAs or shRNAs to Min6 insulinoma cells or primary murine islets. Gene expression was assessed by qPCR, RNAseq analysis, and Western blot analysis. Chromatin enrichment was measured in the Min6 β cell line and primary isolated mouse islets by ChIPseq and ChIP PCR. Immunoprecipitation was used to assess interactions among transcription factors in Min6 cells and isolated mouse islets. Activation of caspase 3 by immunoblotting or by irreversible binding to a fluorescent inhibitor was taken as an indication of commitment to an apoptotic fate. Results RNASeq identified a set of PDX1, ATF4 and ATF5 co-regulated genes enriched in stress and apoptosis functions. We further identified stress induced interactions among PDX1, ATF4, and ATF5. PDX1 chromatin occupancy peaks were identified over composite C/EBP-ATF (CARE) motifs of 26 genes; assessment of a subset of these genes revealed co-enrichment for ATF4 and ATF5. PDX1 occupancy over CARE motifs was conserved in the human orthologs of 9 of these genes. Of these, Glutamate Pyruvate Transaminase 2 (Gpt2) , Cation transport regulator 1 (Chac1) , and Solute Carrier Family 7 Member 1 (Slc7a1) induction by stress was conserved in human islets and abrogated by deficiency of Pdx1 , Atf4 , and Atf5 in Min6 cells. Deficiency of Gpt2 reduced β cell susceptibility to stress induced apoptosis in both Min6 cells and primary islets. Conclusions Our results identify a novel PDX1 stress inducible complex (es) that regulates expression of stress and apoptosis genes to govern β cell survival. Graphical abstract Image 1 Highlights • PDX1 binds to composite CEBP/ATF (CARE) sites of stress and apoptosis genes. • A novel stress inducible transcriptional complex involving PDX1, ATF4, and ATF5 is discovered. • Novel stress induced targets of the complex involved in fate decisions are identified. • Silencing of one of these targets, Gpt2, protects β cells from apoptosis due to stress. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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44. Hypermethylated in cancer 1 (HIC1) mediates high glucose induced ROS accumulation in renal tubular epithelial cells by epigenetically repressing SIRT1 transcription.
- Author
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Zeng, Sheng, Wu, Xiaoyan, Chen, Xuyang, Xu, Huihui, Zhang, Tao, and Xu, Yong
- Abstract
Abstract Reactive oxygen species (ROS) is a key regulator of an array of physiological and pathological processes. While essential for the host defense mechanism, excessive ROS generation and/or deficient clearance is blamed for the pathogenesis of human diseases. In the present study, we investigated the regulatory role of hypermethylated in cancer 1 (HIC1), a transcription factor, in high glucose-induced ROS accumulation in renal tubular epithelial cells (HK-2). Treatment with high glucose (HG) not only markedly up-regulated HIC1 expression but prompted its translocation into the nucleus. HG stimulation promoted HIC1 binding to the promoter of SIRT1, a known HIC1 target with anti-oxidative ability. The recruitment of HIC1 to the SIRT1 promoter was paralleled by the enrichment of trimethylated histone H3K27 and 5‑methyl cytosine, two well-characterized markers for trans-repression. HIC1 silencing with small interfering RNA abrogated SIRT1 repression by HG and at the same time weakened ROS accumulation in HK-2 cells. Knockdown or pharmaceutical inhibition of SIRT1 preempted the effect of HIC1 depletion by restoring ROS accumulation and down-regulating the expression of antioxidant genes. Mechanistically, HIC1 interacted with and recruited EZH2, an H3K27 trimethyltransferase, and DNA methyltransferase 1 (DNMT1) to repress SIRT1 transcription in response to HG stimulation. Depletion or inhibition of EZH2 or DNMT1 rescued SIRT1 expression and blocked ROS accumulation in HG-treated HK-2 cells. In conclusion, our data suggest that epigenetic repression of SIRT1 by HIC1 may contribute to HG-induced elevation of ROS levels in renal tubular epithelial cells. Highlights • HIC1 up-regulation parallels augmented ROS levels in the kidneys in diabetic mice. • High glucose (HG) activates HIC1 in renal epithelial cells. • HIC1 recruits EZH2 and DNMT1 to repress SIRT1 transcription in response to HG. • EZH2 silencing or inhibition relieves SIRT1 repression by HG. • DNMT1 silencing or inhibition attenuates SIRT1 repression by HG. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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45. Interaction of positive coactivator 4 with histone 3.3 protein is essential for transcriptional activation of the luteinizing hormone receptor gene.
- Author
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Zhao, Peng, Kavarthapu, Raghuveer, Anbazhagan, Rajakumar, Liao, Mingjuan, and Dufau, Maria L.
- Abstract
Abstract The luteinizing hormone receptor (LHR) is essential for sexual development and reproduction in mammals. We have established that Sp1 has a central role in derepression of LHR gene transcription induced by Trichostatin A (TSA) in MCF7 cells. Moreover, the co-activator PC4 which associates directly with Sp1 at the LHR promoter is essential for TSA-mediated LHR transcription. This study explores interactions of PC4 with histone proteins, which presumably triggers chromatin modifications during LHR transcriptional activation. TSA treatment of MCF7 cells expressing PC4-Flag protein induces acetylation of histone 3 (H3) and immunoprecipitation (IP) studies revealed its interaction with PC4-Flag protein. MS/MS analysis of the protein complex obtained after IP from TSA treated samples detected H3.3 acetylated at K9, K14, K18, K23 and K27 as a PC4 interacting protein. The association of PC4 with H3.3 was corroborated by IP and re-ChIP using H3.3 antibody. Similarly, IP and re-ChIP showed association of PC4 with H3 acetylated protein. Knockdown of PC4 in MCF7 cells reduced H3.3 enrichment, H3 acetylation at the Lys sites and LHR promoter activity in TSA treated cells despite an increase in H3 and H3.3 protein induced by TSA, linking PC4 to H3 acetylation and LHR transcription. Depletion of H3.3 A/B in MCF7 cells impair chromatin accessibility and enrichment of Pol II and TFIIB at the LHR promoter and its activation, resulting in marked reduction of LHR gene expression. Together, these findings point to the critical role of PC4 and its association with acetylated H3.3 in TSA-induced LHR gene transcription. Highlights • Interaction of PC4 with the histone variant, H3.3, is required for LHR transcription. • Acetylation of H3.3 leads to increase in chromatin accessibility and gene transcription. • H3.3 knock-down impairs the enrichment of Pol II and TFIIB at the LHR promoter and its TSA-induced activation. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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46. Epigenetic activation of PERP transcription by MKL1 contributes to ROS-induced apoptosis in skeletal muscle cells.
- Author
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Li, Zilong, Chen, Baoyu, Dong, Wenhui, Xu, Wenping, Song, Mingzi, Fang, Mingming, Guo, Junli, and Xu, Yong
- Abstract
Abstract Excessive reactive oxygen species (ROS) causes irreparable damages to cells and commit cells to programmed cell death or apoptosis. A panel of well-documented pro-apoptotic genes, including p53 apoptosis effector related to PMP-22 (PERP), are up-regulated and collectively mediate ROS induced apoptosis. The epigenetic mechanism whereby ROS stimulates PERP transcription, however, lacks in-depth characterization. Here we report that the transcriptional modulator megakaryocytic leukemia 1 (MKL1) is activated by H 2 O 2 treatment in skeletal muscle cells (C2C12). Small interfering RNA (siRNA) mediated silencing or small-molecule compound (CCG-1423) mediated inhibition of MKL1 attenuated H 2 O 2 induced apoptosis of C2C12 cells. Over-expression of MKL1 potentiated trans-activation of PERP whereas MKL1 ablation/inhibition abrogated the induction of PERP by H 2 O 2 in C2C12 cells. Mechanistically, MKL1 interacted with and was recruited to the PERP promoter by the transcription factor E2F1. Once bound to the PERP promoter, MKL1 engaged the histone demethylase KDM3A to modulate the chromatin structure surrounding the PERP promoter thereby leading to PERP trans-activation. Depletion of either E2F1 or KDM3A blocked the induction of PERP by H 2 O 2. In conclusion, our data illustrate a novel epigenetic pathway that links PERP transcription to ROS-induced apoptosis in skeletal muscle cells. Highlights • H 2 O 2 treatment activates MKL1 in skeletal muscle cells. • MKL1 depletion or inhibition attenuates H 2 O 2 induced apoptosis. • MKL1 cooperates with E2F1 to activate PERP transcription. • MKL1 recruits KDM3A to activate PERP transcription. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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47. 2D DIGE proteomic analysis reveals fasting‐induced protein remodeling through organ‐specific transcription factor(s) in mice.
- Author
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Kamata, Shotaro, Yamamoto, Junya, Ohtani, Haruka, Tosaka, Yuka, Yoshikawa, Sayumi, Akahoshi, Noriyuki, and Ishii, Isao
- Subjects
TRANSCRIPTION factors ,INTERMITTENT fasting ,PROTEOMICS ,GENE expression in mammals ,DIAGNOSTIC use of polymerase chain reaction - Abstract
Overnight fasting is a routine procedure before surgery in clinical settings. Intermittent fasting is the most common diet/fitness trend implemented for weight loss and the treatment of lifestyle‐related diseases. In either setting, the effects not directly related to parameters of interest, either beneficial or harmful, are often ignored. We previously demonstrated differential activation of cellular adaptive responses in 13 atrophied/nonatrophied organs of fasted mice by quantitative PCR analysis of gene expression. Here, we investigated 2‐day fasting‐induced protein remodeling in six major mouse organs (liver, kidney, thymus, spleen, brain, and testis) using two‐dimensional difference gel electrophoresis (2D DIGE) proteomics as an alternative means to examine systemic adaptive responses. Quantitative analysis of protein expression followed by protein identification using matrix‐assisted laser desorption ionization–time‐of‐flight mass spectrometry (MALDI‐TOFMS) revealed that the expression levels of 72, 26, and 14 proteins were significantly up‐ or downregulated in the highly atrophied liver, thymus, and spleen, respectively, and the expression levels of 32 proteins were up‐ or downregulated in the mildly atrophied kidney. Conversely, there were no significant protein expression changes in the nonatrophied organs, brain and testis. Upstream regulator analysis highlighted transcriptional regulation by peroxisome proliferator‐activated receptor alpha (PPARα) in the liver and kidney and by tumor protein/suppressor p53 (TP53) in the thymus, spleen, and liver. These results imply of the existence of both common and distinct adaptive responses between major mouse organs, which involve transcriptional regulation of specific protein expression upon short‐term fasting. Our data may be valuable in understanding systemic transcriptional regulation upon fasting in experimental animals. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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48. The histone methyltransferase SETD1A regulates thrombomodulin transcription in vascular endothelial cells.
- Author
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Li, Zilong, Chen, Baoyu, Weng, Xinyu, Yu, Liming, Song, Mingzi, Fang, Mingming, Guo, Junli, and Xu, Yong
- Abstract
Thrombomodulin (TM, encoded by the THBD gene) expressed in vascular endothelial cells plays pivotal roles maintaining the equilibrium of coagulation and anti-coagulation. TM levels can be regulated at the transcriptional level although the epigenetic mechanism is underexplored. Here we report that transcriptional activation of TM in both immortalized vascular endothelial cells (EAhy926) and primary human aortic endothelial cells (HAEC) by all-trans retinoic acid (RA) paralleled accumulation of trimethylated histone H3K4, a prominent marker for active chromatin, surrounding the THBD promoter. RA treatment up-regulated the expression of SETD1A (SET1), a dedicated H3K4 methyltransferase, and augmented SETD1A occupancies on the THBD promoter. Further analysis revealed that the sequence-specific transcription factor Kruppel-like factor 4 (KLF4) interacted with and recruited SETD1A to the THBD promoter. Interestingly, SETD1A was recruited to the KLF4 promoter by retinoic acid receptor (RAR) and mediated the up-regulation of KLF4 expression by RA stimulation. In summary, our data illustrate a previously unrecognized pathway in which SETD1A contributes to RA-induced TM expression in vascular endothelial cells by modulating the activity and expression of KLF4. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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49. Heterodimerization of MaTCP proteins modulates the transcription of MaXTH10/11 genes during banana fruit ripening.
- Author
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Song, Chun-Bo, Shan, Wei, Yang, Ying-Ying, Tan, Xiao-Li, Fan, Zhong-Qi, Chen, Jian-Ye, Lu, Wang-Jin, and Kuang, Jian-Fei
- Abstract
The biological processes involved in banana fruit ripening are extremely complex and modulated by a number of genes such as transcription factors (TFs). Although TFs like MADS, ERF and NAC are implicated in controlling banana ripening, little is known about other TFs such as TCP in this process. In this work, 25 MaTCPs named MaTCP1 to MaTCP25 were characterized from our previously reported transcriptomes related to banana ripening. Expression analysis revealed that these MaTCPs displayed differential expression patterns during the progression of banana ripening. Particularly, MaTCP5 , MaTCP19 and MaTCP20 were ethylene-inducible and nuclear-localized, with MaTCP5 and MaTCP20 acting as transcriptional activators while MaTCP19 being a transcriptional inhibitor. Moreover, MaTCP5 and MaTCP20 promoted the transcription of MaXTH10 / 11 that may play a role in fruit softening during banana ripening, whereas MaTCP19 repressed their transcription, by directly binding to their promoters. Importantly, protein-protein interaction assays demonstrated that MaTCP20 physically interacts with MaTCP5 and MaTCP19 to form heterodimers in vitro and in vivo , and these protein complexes affects their transcriptional activities in regulating the target genes. Taken together, our results provide an overview of the interactions between MaTCPs in controlling the ripening-associated genes and lay a foundation for further investigation of MaTCP gene family in regulating banana fruit ripening. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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50. The brassinosteroid-regulated transcription factors BZR1/BES1 function as a coordinator in multisignal-regulated plant growth.
- Author
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Li, Qian-Feng, Lu, Jun, Yu, Jia-Wen, Zhang, Chang-Quan, He, Jun-Xian, and Liu, Qiao-Quan
- Abstract
BZR1 and BES1 are key transcription factors of brassinosteroid (BR) signaling and represent the integration node of numerous signaling cascades. Their direct target genes have been identified, and BZR1/BES1-DNA interactions have been experimentally verified. Importantly, BZR1/BES1 also integrate different growth and development events via direct protein-protein interactions. For instance, DELLAs, PIFs, ARF6, and PKL, all directly interact with BZR1/BES1, forming a BZR1/BES1-centered regulatory network to coordinate cell elongation. By dissecting various BZR1/BES1-mediated BR responses, the concept that BZR1/BES1 act as an integration hub in multisignal-regulated plant growth and development was developed. The regulation of BZR1/BES1 is dynamic and multifaceted, including phosphorylation status, activity, and stability. Moreover, certain epigenetic modification mechanisms are involved in BZR1/BES1's regulation of gene expression. Herein, we review recent advances in BZR1/BES1-mediated molecular connections between BR and other pathways, highlighting the central role of the BZR1/BES1 interactome in optimizing plant growth and development. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
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