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Heat-shock transcription factors (HSFs) are crucial for regulating plant responses to heat and various stresses, as well as for maintaining normal cellular functions and plant development. HSFA9 and HSFA2 are two of the Arabidopsis class A HSFs and their expressions are dramatically induced in response to heat shock (HS) stress among all 21 Arabidopsis HSFs. However, the detailed biological roles of their cooperation have not been fully characterized. In this study, we employed an integrated approach that combined bioinformatics, molecular genetics and computational analysis to identify and validate the molecular mechanism that controls seed longevity and thermotolerance in Arabidopsis. The acquisition of tolerance to deterioration was accompanied by a significant transcriptional switch that involved the induction of primary metabolism, reactive oxygen species and unfolded protein response, as well as the regulation of genes involved in response to dehydration, heat and hypoxia. In addition, the cis -regulatory motif analysis in normal stored and controlled deterioration treatment (CDT) seeds confirmed the CDT-repressed genes with heat-shock element (HSE) in their promoters. Using a yeast two-hybrid and molecular dynamic interaction assay, it is shown that HSFA9 acted as a potential regulator that can interact with HSFA2. Moreover, the knock-out mutants of both HSFA9 and HSFA2 displayed a significant reduction in seed longevity. These novel findings link HSF transcription factors with seed deterioration tolerance and longevity. [ABSTRACT FROM AUTHOR]

Lack of phosphorus (P) is a major environmental factor affecting rapeseed (Brassica napus. L) root growth and development. For breeding purposes, it is crucial to identify the molecular mechanisms underlying root system architecture traits that confer low-P tolerance in rapeseed. Natural variations in the glycine-rich protein gene BnGRP1 were analysed in the natural population of 400 rapeseed cultivars under low-P stress through genome-wide association study and transcriptome analysis. Based on 11 single nucleotide polymorphism mutations in the BnGRP1 sequence, 10 haplotypes (Hap) were formed. Compared with the other types, the cultivar BnGRP1 Hap1 in the panel demonstrated the longest root length and heaviest root weight. BnGRP1 Hap1 overexpression in rapeseed led to enhanced low-P tolerance. CRISPR/Cas9-derived BnGRP1 Hap4 knockout mutations in rapeseed can lead to sensitivity to low-P stress. Furthermore, BnGRP1 Hap1 influences the expression of the phosphate transporter 1 gene (PHT1) associated with P absorption. Overall, the findings of this study highlight new insights into the mechanisms of GRP1 enhancement of low-P tolerance in rapeseed. [ABSTRACT FROM AUTHOR]

Phosphorus (P) deficiency is a major factor constraining plant growth and yield production worldwide because it is essential for living cells and organisms. To avoid disadvantageous genetic correlations between growth duration and root system, traits are critical in developing oilseed rape cultivars that use P efficiently. To understand the genetic basis underlying the correlations between root system traits and two levels of P availability in oilseed, we investigated 6091 different expression genes in the shoot and root tissues of the cultivar Eyou Changjia under low and normal P conditions. Subsequently, the Illumina Brassica 60 K single-nucleotide polymorphism (SNP) arrays were used in a diverse and representative core collection of 405 cultivated oilseed rape accessions, and nearly 13,340 functional SNPs with high polymorphisms were genotyped at the threshold interval of candidate genes. Four root system traits were investigated in the oilseed rape accessions in both low and normal P environments. A total of 224 suggestive association loci were identified for root system traits under low and normal P conditions. Eleven were co-located with the interval of quantitative trait loci (QTLs) for the same traits detected in previous studies. Mutation of co-located SNPs with favourable alleles leads to gene sequence mutations or gene expression changes that result in different phenotypes. The interaction between multiple optimal loci and the effect of QTL aggregation of combined haplotype types with C(A3) and A(A7) formed optimal haplotypes and could improve our understanding of molecular mechanisms underlying P efficiency in oilseed rape. [ABSTRACT FROM AUTHOR]

Disruption of epidermal permeability barrier induces an increase in proinflammatory cytokine expression and release, stimulation of epidermal lipid and DNA synthesis, and expression of antimicrobial peptides. Although alterations in epidermal function in the aged skin are known, whether the epidermal transcriptomic responses to barrier disruption differ between aged and young mice remains unknown. Here, we performed RNA sequencing of the epidermis in 2‐month‐ vs. 20‐month‐old mice following barrier disruption with repeated tape‐stripping. At baseline condition, the epidermis of 20‐month‐old mice displayed an upregulation of inflammation‐associated genes and down‐regulation of epidermal structure‐ and development‐related genes in comparison to 2‐month‐old mice. Barrier disruption upregulated expression levels of 327 genes and downregulated 209 genes in 2‐month‐old mice. In 20‐month‐old mice, the numbers of upregulated and down‐regulated genes were 537 and 299, respectively. In comparison to young mice, the prominently upregulated genes in the 20‐month‐old mice were associated with the IL‐17 signalling pathway, while downregulated genes were mainly involved in the cytokine–cytokine receptor interaction pathway. These results indicate that inflammation‐associated signalling pathways are upregulated, while epidermal structure‐ and development‐related genes are downregulated in the epidermis of aged mice, with further aggravation following barrier disruption, suggesting the importance of improving epidermal function in the elderly. [ABSTRACT FROM AUTHOR]

Introduction: Although it is well known that epidermal function changes with aging, the transcriptomic basis and possible signaling pathways for aging-associated functional changes remain largely unknown. Methods: Here, we employed RNA sequencing techniques to assess epidermal gene expression profiles in the epidermis of mice aged 1, 2, 6, 12 and 20 months. Results: A total of 132 genes displayed reductions in expression levels with aging, while expression levels of 406 genes increased with aging. Epidermal gene expression was prominently upregulated in 2-month-old vs 1-month-old mice, while more genes were downregulated in 12-month-old mice. Upregulation of genes associated with immune/inflammatory responses was observed in the epidermis of aged mice in comparison to that of young mice, whereas downregulated signaling pathways in the epidermis of aged mice were primarily involved in metabolism, such as fatty acid elongation, glutathione metabolism and biosynthesis of antibiotics. Some signaling pathways, such as chemokine signaling, cytokine/cytokine receptor interaction signaling and IL-17 signaling pathways, were remarkably upregulated in 12-month-old mice. Steroid synthesis, metabolic pathway, thermogenesis and proteasome pathways were steadily downregulated, starting at 2 months old. Conclusion: These results indicate that the epidermis of aged mice displays an upregulation of genes associated with inflammatory signaling pathways, and downregulation of genes related to metabolic signaling pathways. [ABSTRACT FROM AUTHOR]

Punicalagin, a major ellagitannin isolated from pomegranate, is proved to have various pharmacological activities with an undefined therapy mechanism. The objective of this research was to demonstrate the effect of punicalagin on anti-inflammatory and angiogenic activation in human umbilical vein endothelial cells (HUVECs) and their potential mechanisms. Endothelial-leukocyte adhesion assay was applied to evaluate primary cultures of HUVECs activation following tumor necrosis factor alpha (TNF-α) treatment. The endothelial cell proliferation, migration, permeability and tube formation were assessed by EdU assay, wound migration assay, trans-endothelial electrical resistances (TEER) assay, and capillary-like tube formation assay, respectively. In addition, the expression of relevant proteins was assessed using Western blot analysis. We confirmed that punicalagin could reduce the adhesion of human monocyte cells to HUVECs in vitro and in vivo. Further, punicalagin decreased the expression of mRNA and proteins of ICAM-1 and VCAM-1 in HUVECs. Moreover, punicalagin inhibited permeability, proliferation, migration, and tube formation in VEGF-induced HUVECs, suppressed IKK-mediated activation of NF-κB signaling in TNF-α-induced endothelial cells, and inhibited vascular endothelial growth factor receptor 2 (VEGFR2) activation and downstream p-PAK1. Our findings indicated that punicalagin might have a protective effect on HUVECs activation, which suggested that punicalagin functions through an endothelial mediated mechanism for treating various disorders such as, cancer, rheumatoid arthritis, and cardiovascular disease. [ABSTRACT FROM AUTHOR]

In wild strains of Bacillus, a handful of extracellular natural products act as signals that can regulate multicellular behavior, but relatively little is known about molecular mechanisms' detail. We proposed a previously unreported molecular mechanism for triggering multicellularity in B. velezensis Bs916 by an endogenous cyclic lipopeptide, bacillomycin L. The genome-wide effect on gene expression was caused by the disruption of bacillomycin L gene cluster, and 100 µg/mL bacillomycin L was revealed by quantitative transcriptomics. A total of 878 differentially expressed genes among Bs916, Δbl, and Δbl + 100BL were identified and grouped into 9 functional categories. The transcription levels of 40 candidate genes were further evaluated by RT-qPCR analysis. The expression of eight candidate genes regulated by bacillomycin L in a dose-dependent manner was revealed by LacZ fusion experiment. Although the addition of bacillomycin L could not completely restore the expression levels of the differentially regulated genes in △bl, our results strongly suggest that bacillomycin L acts as a tuning signal of swarming motility and complex biofilm formation by indirectly regulating the expression levels of some two-component systems (TCSs) connector genes, particularly including several Raps that potentially regulate the phosphorylation levels of three major regulators ComA, DegU, and Spo0A. Key points • Proposed model for bacillomycin L regulation in B. velezensis Bs916. • Bacillomycin L can act as an extracellular signal to regulate the phosphorylation levels of three major regulators, ComA, DegU, and Spo0A and control the multicellular processes of vegetative growth, competent, motility, matrix production, sporulation, and autolysis. [ABSTRACT FROM AUTHOR]

Aplastic anemia (AA) is a bone marrow failure syndrome with high morbidity and mortality. Bone marrow (BM)-mesenchymal stem cells (MSCs) are the main components of the BM microenvironment, and dysregulation of BM-MSC adipogenic differentiation is a pathologic hallmark of AA. MicroRNAs (miRNAs/miRs) are crucial regulators of multiple pathological processes such as AA. However, the role of miR-30a-5p in the modulation of BM-MSC adipogenic differentiation in AA remains unclear. The present study aimed to explore the effect of miR-30a-5p on AA BM-MSC adipogenic differentiation and the underlying mechanism. The levels of miR-30a-5p expression and family with sequence similarity 13, member A (FAM13A) mRNA expression in BM-MSCs were quantified using reverse transcription-quantitative (RT-q) PCR. The mRNA expression levels of adipogenesis-associated factors [fatty acid-binding protein 4 (FABP4), lipoprotein lipase (LPL), perilipin-1 (PLIN1), peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer binding protein α (C/EBPα)] were analyzed using RT-qPCR. Lipid droplet accumulation was evaluated using Oil Red O staining in BM-MSCs. The interaction between miR-30a-5p and the FAM13A 3′-untranslated region was identified by TargetScan, and a dual-luciferase reporter assay was used to confirm the interaction. The expression levels of FAM13A and Wnt/β-catenin pathway-related proteins were examined via western blotting. The results showed that miR-30a-5p expression levels were significantly elevated in BM-MSCs from patients with AA compared with those in control subjects (iron deficiency anemia). miR-30a-5p expression levels were also significantly increased in adipose-induced BM-MSCs in a time-dependent manner. miR-30a-5p significantly promoted AA BM-MSC adipogenic differentiation, and significantly enhanced the mRNA expression levels of FABP4, LPL, PLIN1, PPARγ and C/EBPα as well as lipid droplet accumulation. miR-30a-5p was also demonstrated to target FAM13A in AA BM-MSCs. FAM13A significantly reduced BM-MSC adipogenic differentiation by activating the Wnt/β-catenin signaling pathway. In conclusion, miR-30a-5p was demonstrated to serve a role in AA BM-MSC adipogenic differentiation by targeting the FAM13A/Wnt/β-catenin signaling pathway. These findings suggest that miR-30a-5p may be a therapeutic target for AA. [ABSTRACT FROM AUTHOR]

Endoplasmic reticulum (ER) stress and mitochondrial dysfunction play a pivotal role in the pathological process of sepsis-induced acute lung injury (ALI). Quercetin has been proved to exert anti-inflammation in ALI. This study aimed to explore the protection mechanism of quercetin against sepsis-induced ALI via suppressing ER stress and mitochondrial dysfunction. Cecal ligation and puncture (CLP) mouse model was established to mimic sepsis, and LPS was used to stimulate murine lung epithelial (MLE-12) cells. We observed that quercetin ameliorated pulmonary pathological lesion and oxidative damage in sepsis-induced mice. In LPS-stimulated MLE-12 cells, quercetin could inhibit the level of ER stress as evidenced by decreased mRNA expression of PDI, CHOP, GRP78, ATF6, PERK, IRE1α and improve mitochondrial function, as presented by increased MMP, SOD level and reduced production of ROS, MDA. Meanwhile, transcriptome analysis revealed that quercetin upregulated SIRT1/AMPK mRNA expression. Furthermore, we used siRNA to knockdown SIRT1 in MLE-12 cells, and we found that SIRT1 knockdown could abrogate the quercetin-elicited antioxidation in vitro. Therefore, quercetin could protect against sepsis-induced ALI by suppressing oxidative stress-mediated ER stress and mitochondrial dysfunction via induction of the SIRT1/AMPK pathways. • The present study linked the anti-inflammatory and antioxidant of quercetin to endoplasmic reticulum (ER) stress and mitochondrial dysfunction. • In this study, we focused on the protective effects of quercetin on sepsis-induced ER stress and mitochondrial dysfunction via activating the SIRT1/AMPK pathway and its potential therapeutic effects on sepsis-induced ALI. I feel that we provided the evidence that sepsis destroys alveolar epithelial cells by causing ER stress and mitochondrial dysfunction leading to acute lung injury. Notably, quercetin mitigated ER stress and mitochondrial dysfunction through the SIRT1/AMPK pathways both in vivo and in vitro. • To further explore the underlying mechanism of quercetin on ALI, we performed a transcriptome study by RNA-seq. Transcriptome analysis revealed that quercetin markedly elevated the mRNA level of SIRT1 and AMPK. [ABSTRACT FROM AUTHOR]