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BACH1 plays an important role in promoting cancer. This study aims to further verify the relationship between the expression level of BACH1 in lung adenocarcinoma prognosis, as well as the influence of BACH1 expression on lung adenocarcinoma and the potential mechanism. The expression level of BACH1 in lung adenocarcinoma and its relationship with prognosis was evaluated by lung adenocarcinoma tissue microarray analysis combined with bioinformatics approaches. Gene knockdown and overexpression were used to investigate the functions and molecular mechanisms of BACH1 in lung adenocarcinoma cells. The regulatory downstream pathways and target genes of BACH1 in lung adenocarcinoma cells were explored by bioinformatics and RNA sequencing data analysis, real-time PCR, western blot analysis, and cell immunofluorescence and cell adhesion assays. Chromatin immunoprecipitation and dual-luciferase reporter assays were carried out to verify the target gene binding site. In the present study, BACH1 is abnormally highly expressed in lung adenocarcinoma tissues, and high BACH1 expression is negatively correlated with patient prognosis. BACH1 promotes the migration and invasion of lung adenocarcinoma cells. Mechanistically, BACH1 directly binds to the upstream sequence of the ITGA2 promoter to promote ITGA2 expression, and the BACH1-ITGA2 axis is involved in cytoskeletal regulation in lung adenocarcinoma cells by activating the FAK-RAC1-PAK signaling pathway. Our results indicated that BACH1 positively regulates the expression of ITGA2 through a transcriptional mechanism, thereby activating the FAK-RAC1-PAK signaling pathway to participate in the formation of the cytoskeleton in tumor cells and then promoting the migration and invasion of tumor cells., (© 2023 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Plants possess well-developed light sensing mechanisms and signal transduction systems for regulating photomorphogenesis. ELONGATED HYPOCOTYL5 (HY5), a basic leucine zipper (bZIP) transcription factor, has been extensively characterized in dicots. In this study, we show that OsbZIP1 is a functional homolog of Arabidopsis (Arabidopsis thaliana) HY5 (AtHY5) and is important for light-mediated regulation of seedling and mature plant development in rice (Oryza sativa). Ectopic expression of OsbZIP1 in rice reduced plant height and leaf length without affecting plant fertility, which contrasts with OsbZIP48, a previously characterized HY5 homolog. OsbZIP1 is alternatively spliced, and the OsbZIP1.2 isoform lacking the CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1)-binding domain regulated seedling development in the dark. Rice seedlings overexpressing OsbZIP1 were shorter than the vector control under white and monochromatic light conditions, whereas RNAi knockdown seedlings displayed the opposite phenotype. While OsbZIP1.1 was light-regulated, OsbZIP1.2 showed a similar expression profile in both light and dark conditions. Due to its interaction with OsCOP1, OsbZIP1.1 undergoes 26S proteasome-mediated degradation under dark conditions. Also, OsbZIP1.1 interacted with and was phosphorylated by CASEIN KINASE2 (OsCK2α3). In contrast, OsbZIP1.2 did not show any interaction with OsCOP1 or OsCK2α3. We propose that OsbZIP1.1 likely regulates seedling development in the light, while OsbZIP1.2 is the dominant player under dark conditions. The data presented in this study reveal that AtHY5 homologs in rice have undergone neofunctionalization, and alternative splicing of OsbZIP1 has increased the repertoire of its functions., Competing Interests: Conflict of interest statement. None declared., (© American Society of Plant Biologists 2023. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Competing Interests: Conflict of interest statement. None declared.

Epstein-Barr virus (EBV) and Plasmodium falciparum have a well described role in the development of endemic Burkitt lymphoma (BL), yet the mechanisms involved remain unknown. A major hallmark of malarial disease is hemolysis and bystander eryptosis of red blood cells, which causes release of free heme in large quantities into peripheral blood. We hypothesized that heme released during malaria infection drives differentiation of latently infected EBV-positive B cells, resulting in viral reactivation and release of infectious virus. To test this hypothesis, we used the EBV-positive Mutu I B-cell line and treated with hemin (the oxidized form of heme) and evaluated evidence of EBV reactivation. Hemin treatment resulted in the expression of EBV immediate early, early and late lytic gene transcripts. In addition, expression of CD138, a marker of plasma cells was co-expressed with the late lytic protein gp350 on hemin treated Mutu I cells. Finally, DNase-resistant EBV DNA indicative of virion production was detected in supernatant. To assess the transcriptional changes induced by hemin treatment, RNA sequencing was performed on mock- and hemin-treated Mutu I cells, and a shift from mature B cell transcripts to plasma cell transcripts was identified. To identify the mechanism of hemin-induced B cell differentiation, we measured levels of the plasma cell transcriptional repressor, BACH2, that contains specific heme binding sites. Hemin treatment caused significant degradation of BACH2 by 24 hours post-treatment in four BL cell lines (two EBV positive, two EBV negative). Knockdown of BACH2 in Mutu I cells using siRNAs significantly increased CD138+gp350+ cells to levels similar to treatment with hemin. This suggested that hemin induced BACH2 degradation was responsible for plasma cell differentiation and viral reactivation. Together, these data support a model where EBV reactivation can occur during malaria infection via heme modulation, providing a mechanistic link between malaria and EBV., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Burnet et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Regulator of calcineurin 1.4 (RCAN1.4) is a functionally downregulated metastasis progression suppressor (MPS) in thyroid cancer; however, the mechanisms for RCAN1.4 loss in thyroid cancer have not yet been reported. The RCAN1.4 promoter and gene contain several cytosine-guanine (CG)-rich regions, some of which are reported to be hypermethylated in nonthyroid tissues. We, therefore, hypothesized that RCAN1.4 downregulation in thyroid cancer was in part due to hypermethylation. Methods: Studies were performed in 5 thyroid cancer cell lines (TPC1, FTC133, BCPAP, C643, and 8505C) with different genetic drivers, and in 18 paired normal and thyroid cancer human thyroid cancer tissues. Basal RCAN1.4 messenger RNA (mRNA) and protein levels were assessed in all of the cell lines. Cell lines with lowest RCAN1.4 expression levels were treated with the DNA methyl transferase inhibitor, decitabine. Normal/tumor tissue pairs were analyzed for methylation of three CG-rich regions both by capture of methylated DNA by MBD2 protein and by methylation-specific polymerase chain reaction (MSPCR). Results: In all assessed cell lines, RCAN1.4 mRNA and protein levels increased after decitabine treatment. In silico analysis of the RCAN1.4 gene identified 3 CG-rich regions as possible methylation targets: 1 in the proximal promoter and 2 in intron 1. Hypermethylation of the intron 1 CG-rich regions was identified by both the capture method and MSPCR. In contrast, hypermethylation of the CG-rich region of the proximal promoter was not identified. Gene expression confirmed that hypermethylation in thyroid cancer samples in intron 1 of RCAN1.4 was associated with lower levels of RCAN1.4 mRNA. Finally, the cancer samples demonstrated increased NFE2L3 expression, a downstream marker of functional RCAN1.4 loss. Conclusions: The MPS gene, RCAN1.4, is downregulated in thyroid cancer cells and human thyroid cancer in part by hypermethylation of CG-rich regions in intron 1.

BACH2-related immunodeficiency and autoimmunity (BRIDA) is an inborn error of immunity, newly reported in 2017, presenting with symptoms of immunoglobulin deficiency and ongoing colitis. Studies using a mouse model have demonstrated that BACH2 deficiency predisposes individuals to systemic lupus erythematosus (SLE); however, no BACH2 deficiency has been reported in SLE patients. Here we describe a patient with BRIDA presenting with early-onset SLE, juvenile dermatomyositis, and IgA deficiency. Whole exome sequencing analysis of the patient and her parents revealed a novel heterozygous point mutation in BACH2, c.G1727T, resulting in substitution of a highly conserved arginine with leucine (R576L), which is predicted to be deleterious, in the patient and her father. Reduced BACH2 expression and deficient transcriptional repression of the BACH2 target, BLIMP1, were detected in PBMCs or lymphoblastoid cell lines of our patient. Notably, extreme reduction of memory B cells was detected in the patient's father, although he had no obvious symptoms. SLE symptoms and recurrent fever were relieved by treatment with prednisone combined with tofacitinib. Thus, we present the second report of BRIDA and demonstrate that BACH2 may be a monogenic cause of SLE., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Excessive accumulation of misfolded proteins in the endoplasmic reticulum (ER) causes ER stress, which is an underlying cause of major crop losses and devastating human conditions. ER proteostasis surveillance is mediated by the conserved master regulator of the unfolded protein response (UPR), Inositol Requiring Enzyme 1 (IRE1), which determines cell fate by controlling pro-life and pro-death outcomes through as yet largely unknown mechanisms. Here we report that Arabidopsis IRE1 determines cell fate in ER stress by balancing the ubiquitin-proteasome system (UPS) and UPR through the plant-unique E3 ligase, PHOSPHATASE TYPE 2CA (PP2CA)-INTERACTING RING FINGER PROTEIN 1 (PIR1). Indeed, PIR1 loss leads to suppression of pro-death UPS and the lethal phenotype of an IRE1 loss-of-function mutant in unresolved ER stress in addition to activating pro-survival UPR. Specifically, in ER stress, PIR1 loss stabilizes ABI5, a basic leucine zipper (bZIP) transcription factor, that directly activates expression of the critical UPR regulator gene, bZIP60, triggering transcriptional cascades enhancing pro-survival UPR. Collectively, our results identify new cell fate effectors in plant ER stress by showing that IRE1's coordination of cell death and survival hinges on PIR1, a key pro-death component of the UPS, which controls ABI5, a pro-survival transcriptional activator of bZIP60., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Ferroptosis is a regulated cell death induced by iron-dependent lipid peroxidation. The heme-responsive transcription factor BTB and CNC homology 1 (BACH1) promotes ferroptosis by repressing the transcription of genes involved in glutathione (GSH) synthesis and intracellular labile iron metabolism, which are key regulatory pathways in ferroptosis. We found that BACH1 re-expression in Bach1-/- immortalized mouse embryonic fibroblasts (iMEFs) can induce ferroptosis upon 2-mercaptoethanol removal, without any ferroptosis inducers. In these iMEFs, GSH synthesis was reduced, and intracellular labile iron levels were increased upon BACH1 re-expression. We used this system to investigate whether the major ferroptosis regulators glutathione peroxidase 4 (Gpx4) and apoptosis-inducing factor mitochondria-associated 2 (Aifm2), the gene for ferroptosis suppressor protein 1, are target genes of BACH1. Neither Gpx4 nor Aifm2 was regulated by BACH1 in the iMEFs. However, we found that BACH1 represses AIFM2 transcription in human pancreatic cancer cells. These results suggest that the ferroptosis regulators targeted by BACH1 may vary across different cell types and animal species. Furthermore, we confirmed that the ferroptosis induced by BACH1 re-expression exhibited a propagating effect. BACH1 re-expression represents a new strategy for inducing ferroptosis after GPX4 or system Xc- suppression and is expected to contribute to future ferroptosis research., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.)

The deubiquitinating enzyme USP14 has been established as a crucial regulator in various diseases, including tumors, neurodegenerative diseases, and metabolic diseases, through its ability to stabilize its substrate proteins. Our group has utilized proteomic techniques to identify new potential substrate proteins for USP14, however, the underlying signaling pathways regulated by USP14 remain largely unknown. Here, we demonstrate the key role of USP14 in both heme metabolism and tumor invasion by stabilizing the protein BACH1. The cellular oxidative stress response factor NRF2 regulates antioxidant protein expression through binding to the antioxidant response element (ARE). BACH1 can compete with NRF2 for ARE binding, leading to the inhibition of the expression of antioxidant genes, including HMOX-1. Activated NRF2 also inhibits the degradation of BACH1, promoting cancer cell invasion and metastasis. Our findings showed a positive correlation between USP14 expression and NRF2 expression in various cancer tissues from the TCGA database and normal tissues from the GTEx database. Furthermore, activated NRF2 was found to increase USP14 expression in ovarian cancer (OV) cells. The overexpression of USP14 was observed to inhibit HMOX1 expression, while USP14 knockdown had the opposite effect, suggesting a role for USP14 in regulating heme metabolism. The depletion of BACH1 or inhibition of heme oxygenase 1 (coded by HMOX-1) was also found to significantly impair USP14-dependent OV cell invasion. In conclusion, our results highlight the importance of the NRF2-USP14-BACH1 axis in regulating OV cell invasion and heme metabolism, providing evidence for its potential as a therapeutic target in related diseases., Competing Interests: Declaration of competing interest All authors have no conflict of interests to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Gene expression stochasticity is inherent in the functional properties and evolution of biological systems, creating non-genetic cellular individuality and influencing multiple processes, including differentiation and stress responses. In a distinct form of non-transcriptional noise, we find that interactions of the yeast translation machinery with the GCN4 mRNA 5'UTR, which underpins starvation-induced regulation of this transcriptional activator gene, manifest stochastic variation across cellular populations. We use flow cytometry, fluorescence-activated cell sorting and microfluidics coupled to fluorescence microscopy to characterize the cell-to-cell heterogeneity of GCN4-5'UTR-mediated translation initiation. GCN4-5'UTR-mediated translation is generally not de-repressed under non-starvation conditions; however, a sub-population of cells consistently manifests a stochastically enhanced GCN4 translation (SETGCN4) state that depends on the integrity of the GCN4 uORFs. This sub-population is eliminated upon deletion of the Gcn2 kinase that phosphorylates eIF2α under nutrient-limitation conditions, or upon mutation to Ala of the Gcn2 kinase target site, eIF2α-Ser51. SETGCN4 cells isolated using cell sorting spontaneously regenerate the full bimodal population distribution upon further growth. Analysis of ADE8::ymRuby3/ GCN4::yEGFP cells reveals enhanced Gcn4-activated biosynthetic pathway activity in SETGCN4 cells under non-starvation conditions. Computational modeling interprets our experimental observations in terms of a novel translational noise mechanism underpinned by natural variations in Gcn2 kinase activity., (© The Author(s) 2023. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Background: Basic leucine zipper (bZIP) proteins are important transcription factors in plants. To study the role of bZIP transcription factors in walnut explant browning, this study used bioinformatics software to analyze walnut bZIP gene family members, along with their transcript levels in different walnut tissues, to evaluate the transcriptional expression of this gene family during the primary culture of walnut explants and to reveal the mechanism of action of walnut bZIP genes in walnut explant browning., Results: The results identified 65 JrbZIP genes in the walnut genome, which were divided into 8 subfamilies and distributed on 16 chromosomes. The results of transcriptome data analysis showed that there were significant differences in the expression of four genes, namely, JrbZIP55, JrbZIP70, JrbZIP72, and JrbZIP88, under both vermiculite and agar culture conditions. There were multiple hormone (salicylic acid, abscisic acid, auxin, and gibberellin) signaling and regulatory elements that are responsive to stress (low temperature, stress, and defense) located in the promoter regions of JrbZIP55, JrbZIP70, JrbZIP72, and JrbZIP88. The walnut JrbZIP55 protein and Arabidopsis bZIP42 protein are highly homologous, and the proteins interacting with Arabidopsis bZIP42 include the AT2G19940 oxidoreductases, which act on aldehyde or oxygen-containing donors., Conclusion: It is speculated that JrbZIP55 may participate in the regulation of browning in walnut explants., (© 2023. The Author(s).)

Elongated hypocotyls 5 (HY5) is a transcription factor that can be induced by illumination and promotes nitrate uptake in Arabidopsis. However, whether GhHY5 regulates nitrate uptake in cotton is unknown. In this study, the cotton seedlings growing in light and dark conditions were treated with 15 N-labeled nutrient solution to study whether the GhHY5 regulates nitrate uptake in cotton. The results showed that the 15 N content and GhNRT1.1 expression in the light condition were higher than that in the dark condition, indicating that light induced the expression of GhNRT1.1 and subsequently promoted N uptake. Additionally, the expression of GhHY5 in the leaf and root of cotton was induced by light and the expression pattern of GhHY5 in the root was similar to that of GhNRT1.1. Furthermore, when the GhHY5 expression in the root was reduced, the 15 N content and GhNRT1.1 expression were both decreased, indicating that the GhNRT1.1 expression was regulated by GhHY5. The root expression of GhHY5 was decreased in the grafted seedlings which the GhHY5 in the shoot was silenced by VIGS or the seedlings which the hypocotyl was girdled, but the expression of GhHY5 on one side root of the grafted cotton seedling was not changed if the GhHY5 was silenced on the other side root. Thus, we proposed that the light induced shoot-derived GhHY5 gene or GhHY5 protein may be transported from the xylem to the root, regulating the expression of GhHY5 and GhNRT1.1, and thus regulating N uptake at the root of cotton., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Masson SAS. All rights reserved.)

Low temperature and abscisic acid (ABA) are the two main factors that induce anthocyanin synthesis; however, their potential relationships in governing anthocyanin biosynthesis in Solanum lycopersicum (tomato) seedlings remains unclear. Our study revealed the involvement of the transcription factor SlAREB1 in the low-temperature response of tomato seedlings via the ABA-dependent pathway, for a specific temperature range. The overexpression of SlAREB1 enhanced the expression of anthocyanin-related genes and the accumulation of anthocyanins, especially under low-temperature conditions, whereas silencing SlAREB1 dramatically reduced gene expression and anthocyanin accumulation. There is a direct interaction between SlAREB1 and the promoters of SlDFR and SlF3'5'H, which are structural genes that impact anthocyanin biosynthesis. SlAREB1 can regulate anthocyanins through controlling SlDFR and SlF3'5'H expression. Accordingly, SlAREB1 takes charge of regulating anthocyanin biosynthesis in tomato seedlings via the ABA-dependent pathway at low temperatures., (© 2023 Society for Experimental Biology and John Wiley & Sons Ltd.)

A major pharmacological assumption is that lowering disease-promoting protein levels is generally beneficial. For example, inhibiting metastasis activator BACH1 is proposed to decrease cancer metastases. Testing such assumptions requires approaches to measure disease phenotypes while precisely adjusting disease-promoting protein levels. Here we developed a two-step strategy to integrate protein-level tuning, noise-aware synthetic gene circuits into a well-defined human genomic safe harbor locus. Unexpectedly, engineered MDA-MB-231 metastatic human breast cancer cells become more, then less and then more invasive as we tune BACH1 levels up, irrespective of the native BACH1. BACH1 expression shifts in invading cells, and expression of BACH1's transcriptional targets confirm BACH1's nonmonotone phenotypic and regulatory effects. Thus, chemical inhibition of BACH1 could have unwanted effects on invasion. Additionally, BACH1's expression variability aids invasion at high BACH1 expression. Overall, precisely engineered, noise-aware protein-level control is necessary and important to unravel disease effects of genes to improve clinical drug efficacy., (© 2023. The Author(s).)

Introduction: BTB and CNC homology 1 (Bach1) is a protein that antagonizes some actions of nuclear factor erythroid 2-related factor-2 (Nrf2), the master regulator of cytoprotective responses. Bach1 binds to genomic DNA and inhibits the synthesis of antioxidant enzymes, thereby increasing inflammation. Bach1 may be a therapeutic target for mitigating inflammation in chronic kidney disease (CKD) patients. However, no clinical study has been reported on Bach1 in this population. This study aimed to evaluate Bach1 mRNA expression with different treatments for CKD, including conservative treatment (nondialysis), hemodialysis (HD), and peritoneal dialysis (PD)., Methods: Twenty patients undergoing HD (56.5 [19] years), 15 on PD (54 [24] years) and 13 nondialysis patients (63 [10] years, with an estimated glomerular filtration rate of 41 [14] mL/min/1.73 m 2 ) were enrolled in the study. The mRNA expression of Nrf2, NF-kB, heme oxygenase 1 (HO-1), and Bach1 was evaluated in peripheral blood mononuclear cells using quantitative real-time polymerase chain reaction. Malondialdehyde (MDA) was evaluated as a lipid peroxidation marker. Routine biochemical parameters were also evaluated., Findings: As expected, patients on dialysis were more inflamed. Bach1 mRNA expression was significantly higher in patients undergoing HD than in PD and nondialysis patients (p < 0.007). The mRNA expression of HO-1, NF-kB, and Nrf2 was not different in the groups., Conclusion: In conclusion, CKD patients on HD exhibited an upregulation of Bach1 mRNA expression compared to patients on PD treatment and nondialysis CKD patients. The association between Nrf2 and Bach1 expression in these patients warrants further investigation., (© 2023 International Society for Hemodialysis.)

The circadian rhythm disorder and abnormal expression of rhythm genes are related to many diseases, especially cancer. Rhythm gene NFIL3 is involved in energy metabolism and immune cell differentiation, and its aberrant expression is associated with metabolic diseases and inflammation. Previously, numerous studies have shown that aberrant NFIL3 expression is associated with tumorigenesis, progression, and chemotherapy resistance. For instance, NFIL3 performs as a nuclear transcription factor, impacts cell proliferation, represses apoptosis, and promotes cancer cell invasion and metastasis by regulating the transcription of target genes. In addition, NFIL3 expressed in cancer cells influences the type and proportion of infiltrated immune cells in the tumor microenvironment. Increased expression of NFIL3 induces the chemotherapy and immunotherapy resistance in cancer. In this review, we summarized the pathological functions of NFIL3 in tumorigenesis, cancer development, and treatment. The rhythm gene NFIL3 can be used as a promising target in cancer therapy in the future., (© 2023. The Author(s), under exclusive licence to Federación de Sociedades Españolas de Oncología (FESEO).)

Seed germination is the complex adaptive trait of higher plants influenced by a large number of genes and environmental factors. Numerous studies have been performed to better understand how germination is controlled by various environmental factors and applied chemicals, such as cyanide. However, still very little is known about the molecular mechanisms of how extrinsic signals regulate seed germination. Our and previous studies found that non-lethal cyanide treatment promotes seed germination, but the regulatory mechanism is unclear. In this study, we found that a low concentration of cyanide pretreatment significantly enhanced the expression of endo-β-mannanase 5 ( MAN5 ) gene in Arabidopsis thaliana , and the mutation of this gene impaired cyanide-mediated seed germination. In contrast, overexpression of MAN5 gene enhanced Arabidopsis seed germination ability under both normal and salt stress conditions. Further studies showed that the expression of the MAN5 gene was negatively regulated by ABA insensitive 5 (ABI5); In abi5 mutant seeds, the expression of the MAN5 gene was increased and the seed germination rate was accelerated. Additionally, cyanide pretreatment markedly reduced the gene expression of ABI5 in Arabidopsis seeds. Taken together, our data support the involvement of MAN5 as a key gene in cyanide-mediated seed germination and confirm the role of ABI5 as a critical negative factor involved in cyanide-regulated MAN5 gene expression., Competing Interests: The authors declare no conflict of interest.

Human T-cell leukemia virus type 1 (HTLV-1) is the etiologic cause of adult T-cell leukemia/lymphoma (ATL) and encodes a viral oncoprotein (Hbz) that is consistently expressed in asymptomatic carriers and ATL patients, suggesting its importance in the development and maintenance of HTLV-1 leukemic cells. Our previous work found Hbz protein is dispensable for virus-mediated T-cell immortalization but enhances viral persistence. We and others have also shown that hbz mRNA promotes T-cell proliferation. In our current studies, we evaluated the role of hbz mRNA on HTLV-1-mediated immortalization in vitro as well as in vivo persistence and disease development. We generated mutant proviral clones to examine the individual contributions of hbz mRNA, hbz mRNA secondary structure (stem-loop), and Hbz protein. Wild-type (WT) and all mutant viruses produced virions and immortalized T-cells in vitro. Viral persistence and disease development were also evaluated in vivo by infection of a rabbit model and humanized immune system (HIS) mice, respectively. Proviral load and sense and antisense viral gene expression were significantly lower in rabbits infected with mutant viruses lacking Hbz protein compared to WT or virus with an altered hbz mRNA stem-loop (M3 mutant). HIS mice infected with Hbz protein-deficient viruses showed significantly increased survival times compared to animals infected with WT or M3 mutant virus. Altered hbz mRNA secondary structure, or loss of hbz mRNA or protein, has no significant effect on T-cell immortalization induced by HTLV-1 in vitro; however, the Hbz protein plays a critical role in establishing viral persistence and leukemogenesis in vivo., Competing Interests: The authors declare no competing interests that could be perceived to bias this work., (Copyright: © 2023 Maksimova et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Main Conclusion: This study provides an overview of the structure, classification, regulatory mechanisms, and biological functions of the basic (region) leucine zipper transcription factors and their molecular mechanisms in flavonoid, terpenoid, alkaloid, phenolic acid, and lignin biosynthesis. Basic (region) leucine zippers (bZIPs) are evolutionarily conserved transcription factors (TFs) in eukaryotic organisms. The bZIP TFs are widely distributed in plants and play important roles in plant growth and development, photomorphogenesis, signal transduction, resistance to pathogenic microbes, biotic and abiotic stress, and secondary metabolism. Moreover, the expression of bZIP TFs not only promotes or inhibits the accumulation of secondary metabolites in medicinal plants, but also affects the stress response of plants to the external adverse environment. This paper describes the structure, classification, biological function, and regulatory mechanisms of bZIP TFs. In addition, the molecular mechanism of bZIP TFs regulating the biosynthesis of flavonoids, terpenoids, alkaloids, phenolic acids, and lignin are also elaborated. This review provides a summary for in-depth study of the molecular mechanism of bZIP TFs regulating the synthesis pathway of secondary metabolites and plant molecular breeding, which is of significance for the generation of beneficial secondary metabolites and the improvement of plant varieties., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: BATF, as a transcription factor, and CD112, as a receptor for TIGIT, are involved in T-cell exhaustion. We investigated BATF and CD112 gene expression in the peripheral blood mononuclear cells from CLL patients and healthy subjects., Methods: In a case-control study, 33 patients with CLL and 20 sex- and age-matched healthy individual were enrolled. Diagnosis and classification of patients was done according to immunophenotyping via flow cytometry and RAI staging system, respectively. Relative mRNA expression of BATF and CD112 was measured using qRT-PCR., Result: Our results showed that the expression of BATF and CD112 in CLL samples were significantly decreased in comparison those of the healthy controls (P = 0.0236 and P = 0.0002, respectively)., Conclusion: These findings suggest the role of BATF and CD112 not only as a role in T cell exhaustion, but in effector differentiation program in CLL, which warrants further studies in future.

Thioredoxin (TXN) is essential for preserving balance and controlling the intracellular redox state. Most studies have focused on the function of TXN in redox reactions, which is critical for tumor progression. Here, we showed that TXN promotes hepatocellular carcinoma (HCC) stemness properties in a non-redox-dependent manner, which has rarely been reported in previous studies. TXN exhibited upregulated expression in human HCC specimens, which was associated with a poor prognosis. Functional studies showed that TXN promoted HCC stemness properties and facilitated HCC metastasis both in vitro and in vivo. Mechanistically, TXN promoted the stemness of HCC cells by interacting with BTB and CNC homology 1 (BACH1) and stabilized BACH1 expression by inhibiting its ubiquitination. BACH1 was positively correlated with TXN expression and was significantly upregulated in HCC. In addition, BACH1 promotes HCC stemness by activating the AKT/mammalian target of rapamycin (mTOR) pathway. Furthermore, we found that the specific inhibition of TXN in combination with lenvatinib in mice significantly improved the treatment of metastatic HCC. In summary, our data demonstrate that TXN plays a crucial role in HCC stemness and BACH1 plays an integral part in regulating this process by activating the AKT/mTOR pathway. Thus, TXN is a promising target for metastatic HCC therapy., (© 2023 Federation of American Societies for Experimental Biology.)

Cold stress seriously affects plant development, resulting in heavy agricultural losses. L-ascorbic acid (AsA, vitamin C) is an antioxidant implicated in abiotic stress tolerance and metabolism of reactive oxygen species (ROS). Understanding whether and how cold stress elicits AsA biosynthesis to reduce oxidative damage is important for developing cold-resistant plants. Here, we show that the accumulation of AsA in response to cold stress is a common mechanism conserved across the plant kingdom, from single-cell algae to angiosperms. We identified a basic leucine zipper domain (bZIP) transcription factor (TF) of kiwifruit (Actinidia eriantha Benth.), AcePosF21, which was triggered by cold and is involved in the regulation of kiwifruit AsA biosynthesis and defense responses against cold stress. AcePosF21 interacted with the R2R3-MYB TF AceMYB102 and directly bound to the promoter of the gene encoding GDP-L-galactose phosphorylase 3 (AceGGP3), a key conduit for regulating AsA biosynthesis, to up-regulate AceGGP3 expression and produce more AsA, which neutralized the excess ROS induced by cold stress. On the contrary, VIGS or CRISPR-Cas9-mediated editing of AcePosF21 decreased AsA content and increased the generation of ROS in kiwifruit under cold stress. Taken together, we illustrated a model for the regulatory mechanism of AcePosF21-mediated regulation of AceGGP3 expression and AsA biosynthesis to reduce oxidative damage by cold stress, which provides valuable clues for manipulating the cold resistance of kiwifruit., Competing Interests: Conflict of interest statement. The authors declare that they have no competing interests., (© American Society of Plant Biologists 2023. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The transcription factor BTB and CNC homology 1(BACH1) has been linked to coronary artery disease risk by human genome-wide association studies, but little is known about the role of BACH1 in vascular smooth muscle cell (VSMC) phenotype switching and neointima formation following vascular injury. Therefore, this study aims to explore the role of BACH1 in vascular remodeling and its underlying mechanisms. BACH1 was highly expressed in human atherosclerotic plaques and has high transcriptional factor activity in VSMCs of human atherosclerotic arteries. VSMC-specific loss of Bach1 in mice inhibited the transformation of VSMC from contractile to synthetic phenotype and VSMC proliferation and attenuated the neointimal hyperplasia induced by wire injury. Mechanistically, BACH1 suppressed chromatin accessibility at the promoters of VSMC marker genes via recruiting histone methyltransferase G9a and cofactor YAP and maintaining the H3K9me2 state, thereby repressing VSMC marker genes expression in human aortic smooth muscle cells (HASMCs). BACH1-induced repression of VSMC marker genes was abolished by the silencing of G9a or YAP. Thus, these findings demonstrate a crucial regulatory role of BACH1 in VSMC phenotypic transition and vascular homeostasis and shed light on potential future protective vascular disease intervention via manipulation of BACH1., (© The Author(s) 2023. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Adult T-cell leukemia (ATL) is a peripheral T-cell malignancy caused by human T-cell leukemia virus type 1 (HTLV-1). Microsatellite instability (MSI) has been observed in ATL cells. Although MSI results from impaired mismatch repair (MMR) pathway, no null mutations in the genes encoding MMR factors are detectable in ATL cells. Thus, it is unclear whether or not impairment of MMR causes the MSI in ATL cells. HTLV-1 bZIP factor (HBZ) protein interacts with numerous host transcription factors and significantly contributes to disease pathogenesis and progression. Here we investigated the effect of HBZ on MMR in normal cells. The ectopic expression of HBZ in MMR-proficient cells induced MSI, and also suppressed the expression of several MMR factors. We then hypothesized that the HBZ compromises MMR by interfering with a transcription factor, nuclear respiratory factor 1 (NRF-1), and identified the consensus NRF-1 binding site at the promoter of the gene encoding MutS homologue 2 (MSH2), an essential MMR factor. The luciferase reporter assay revealed that NRF-1 overexpression enhanced MSH2 promoter activity, while co-expression of HBZ reversed this enhancement. These results supported the idea that HBZ suppresses the transcription of MSH2 by inhibiting NRF-1. Our data demonstrate that HBZ causes impaired MMR, and may imply a novel oncogenesis driven by HTLV-1., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Masao Matsuoka reports a relationship with Kyowa Kirin Co Ltd that includes: speaking and lecture fees. Masao Matsuoka reports a relationship with Meiji Seika Pharma Co Ltd that includes: speaking and lecture fees. Masao Matsuoka reports a relationship with Bristol Myers Squibb Co that includes: speaking and lecture fees. Masao Matsuoka reports a relationship with Chugai Pharmaceutical Co Ltd that includes: speaking and lecture fees. Akifumi Takaori-Kondo reports a relationship with Ono Pharmaceutical Co Ltd that includes: funding grants., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The floral transition occurs at the shoot apical meristem (SAM) in response to favourable external and internal signals. Among these signals, variations in daylength (photoperiod) act as robust seasonal cues to activate flowering. In Arabidopsis, long-day photoperiods stimulate production in the leaf vasculature of a systemic florigenic signal that is translocated to the SAM. According to the current model, FLOWERING LOCUS T (FT), the main Arabidopsis florigen, causes transcriptional reprogramming at the SAM, so that lateral primordia eventually acquire floral identity. FT functions as a transcriptional coregulator with the bZIP transcription factor FD, which binds DNA at specific promoters. FD can also interact with TERMINAL FLOWER 1 (TFL1), a protein related to FT that acts as a floral repressor. Thus, the balance between FT-TFL1 at the SAM influences the expression levels of floral genes targeted by FD. Here, we show that the FD-related bZIP transcription factor AREB3, which was previously studied in the context of phytohormone abscisic acid signalling, is expressed at the SAM in a spatio-temporal pattern that strongly overlaps with FD and contributes to FT signalling. Mutant analyses demonstrate that AREB3 relays FT signals redundantly with FD, and the presence of a conserved carboxy-terminal SAP motif is required for downstream signalling. AREB3 shows unique and common patterns of expression with FD, and AREB3 expression levels are negatively regulated by FD thus forming a compensatory feedback loop. Mutations in another bZIP, FDP, further aggravate the late flowering phenotypes of fd areb3 mutants. Therefore, multiple florigen-interacting bZIP transcription factors have redundant functions in flowering at the SAM., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Martignago et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Abscisic acid (ABA) is a plant hormone that plays an important regulatory role in plant growth and stress response. The AREB (ABA-responsive element binding protein)/ ABF (ABRE-binding factor) are important ABA-signaling components that participate in abiotic stress response. However, genome-scale analysis of ABF/AREB has not been systemically investigated in tomato. This study was conducted to identify tomato ABF/AREB family members and analyze their response to ABA and abiotic stresses. The results show that a total of 10 ABF/AREB members were identified in tomato, which are randomly distributed on five chromosomes. Domain analysis showed that these members exhibit high protein similarity, especially in the basic leucine zipper (bZIP) domain region. Subcellular localization analysis indicated that all 10 ABF/AREB members are localized in the nucleus. Phylogenetic tree analysis showed that tomato ABF/AREB genes are divided into two groups, and they are similar with the orthologs of other plants. The analysis of cis -acting elements showed that most tomato ABF/AREB genes contain a variety of hormones and stress-related elements. Expression profiles of different tissues indicated that SlABF2 and SlABF10 play an important role in fruit ripening. Finally, qRT-PCR analysis revealed that 10 tomato ABF/AREB genes respond to ABA, with SlABF3 being the most sensitive. SlABF3 , SlABF5 and SlABF10 positively respond to salt and cold stresses. SlABF1 , SlABF3 and SlABF10 are significantly induced under UV radiation treatment. SlABF3 and SlABF5 are significantly induced in osmotic stress. Overall, this study may provide insight into the role of tomato ABF/AREB homologues in plant response to abiotic stresses, which laid a foundation for future functional study of ABF/AREB in tomato., Competing Interests: The authors declare that they have no competing interests., (© 2023 Pan et al.)

Main Conclusion: TabZIP60 is found to interact with TaCDPK30 and act as a positive regulator of ABA synthesis-mediated salt tolerance in wheat. Wheat basic leucine zipper (bZIP) transcription factor (TabZIP60) was previously found to act as a positive regulator of salt resistance. However, its molecular mechanism in response to salt stress in wheat is still unclear. In this study, TabZIP60 was found to interact with wheat calcium-dependent protein kinase (TaCDPK30), which belonged to group III of CDPK family, and was induced by salt, polyethylene glycol, and abscisic acid (ABA) treatments. This mutation of serine 110 in TabZIP60 resulted in no interaction with TaCDPK30. Moreover, TaCDPK30 was involved in interactions with wheat protein phosphatase 2C clade A (TaPP2CA116/TaPP2CA121). TabZIP60-overexpressing wheat plants showed increased salt tolerance, as exhibited by better growth status, higher soluble sugar, and lower malonaldehyde contents of transgenic plants than wild-type wheat cv. Kenong 199 under salt stress. Moreover, transgenic lines showed high ABA content by upregulating ABA synthesis-related gene expression levels. TabZIP60 protein could bind and interact with the promoter of the wheat nine-cis epoxycarotenoid dioxygenase (TaNCED2) gene. Furthermore, TabZIP60 upregulated several stress response gene expression levels, which could also increase the plant's ability to resist salt stress. Thus, these results suggest that TabZIP60 could function as a regulator of ABA synthesis-mediated salt tolerance through interacting with TaCDPK30 in wheat., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The yeast Saccharomyces cerevisiae is a widely used cell factory for protein production. Increasing the protein production capacity of a yeast strain may be beneficial for obtaining recombinant proteins as a product or exerting its competence in consolidated bioprocessing. However, heterologous protein expression usually imposes stress on cells. Improving the cell's ability to cope with stress enhances protein yield. HAC1 is a key transcription factor in the unfolded protein response (UPR). In this study, several genes related to the UPR signal pathway, including unfolded protein sensing, HAC1 mRNA splicing, mRNA ligation, mRNA decay, translation, and Hac1p degradation, were selected as targets to engineer yeast strains. The final engineered strain produced α-amylase 3.3-fold, and human serum albumin 15.3-fold, greater than that of the control strain. Key regulation and metabolic network changes in the engineered strains were identified by transcriptome analysis and physiological characterizations. This study demonstrated that cell engineering with genes relevant to the key node HAC1 in UPR increased protein secretion substantially. The verified genetic modifications of this study provide useful targets in the construction of yeast cell factories for efficient protein production., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: The authors have filed a patent for protecting the protein production in engineered yeast strains., (Copyright © 2023 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.)

APETALA2 (AP2) is well known for regulating the development of floral organs, ovules, seed coats, and the mass of seeds, but the role of AP2 in seed germination remains unclear. Here, we report that AP2 interacts with ABI5 in nuclear speckles and functions in controlling seed germination. Genetic study showed that the abi5 mutation could restore the ABA-sensitive phenotype of ap2 mutants, supporting that AP2 antagonizes ABI5 in ABA signaling and ABA-mediated inhibition of seed germination. In addition, we observed the interactions of AP2 with SnRK2.2, SnRK2.3, and SnRK2.6 in nuclear speckles, suggesting that AP2 plays a multifaceted role in the ABA signaling pathway. Our findings revealed that the interactions of AP2 with SnRK2s and ABI5 are critical for ABA signaling in control of seed germination., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: RNA N 6 -methyladenosine (m 6 A) modification is critical for plant growth and crop yield. m 6 A reader proteins can recognize m 6 A modifications to facilitate the functions of m 6 A in gene regulation. ECT2, ECT3, and ECT4 are m 6 A readers that are known to redundantly regulate trichome branching and leaf growth, but their molecular functions remain unclear., Results: Here, we show that ECT2, ECT3, and ECT4 directly interact with each other in the cytoplasm and perform genetically redundant functions in abscisic acid (ABA) response regulation during seed germination and post-germination growth. We reveal that ECT2/ECT3/ECT4 promote the stabilization of their targeted m 6 A-modified mRNAs, but have no function in alternative polyadenylation and translation. We find that ECT2 directly interacts with the poly(A) binding proteins, PAB2 and PAB4, and maintains the stabilization of m 6 A-modified mRNAs. Disruption of ECT2/ECT3/ECT4 destabilizes mRNAs of ABA signaling-related genes, thereby promoting the accumulation of ABI5 and leading to ABA hypersensitivity., Conclusion: Our study reveals a unified functional model of m 6 A mediated by m 6 A readers in plants. In this model, ECT2/ECT3/ECT4 promote stabilization of their target mRNAs in the cytoplasm., (© 2023. The Author(s).)

Dysfunction of interleukin-10 producing regulatory B cells has been associated with the pathogenesis of autoimmune diseases, but whether regulatory B cells can be therapeutically induced in humans is currently unknown. Here we demonstrate that a subset of activated B cells expresses CD25, and the addition of low-dose recombinant IL-2 to in vitro stimulated peripheral blood and splenic human B cells augments IL-10 secretion. Administration of low dose IL-2, aldesleukin, to patients increases IL-10-producing B cells. Single-cell RNA sequencing of circulating immune cells isolated from low dose IL2-treated patients reveals an increase in plasmablast and plasma cell populations that are enriched for a regulatory B cell gene signature. The transcriptional repressor BACH2 is significantly down-regulated in plasma cells from IL-2-treated patients, BACH2 binds to the IL-10 gene promoter, and Bach2 depletion or genetic deficiency increases B cell IL-10, implicating BACH2 suppression as an important mechanism by which IL-2 may promote an immunoregulatory phenotype in B cells., (© 2023. The Author(s).)

Innate immunity is the first line of host defense against pathogenic invasion in metazoans. The transcription factor basic leucine zipper transcriptional factor ATF-like 3 (BATF3) plays a crucial role in the development of conventional dendritic cells and the program of CD8 + T cell survival and memory, but the role of BATF3 in innate immune responses remains unclear. Here, we show an evolutionarily conserved basic-region leucine zipper (bZIP) transcription factor BATF3/ZIP-10 suppresses innate immune response through repressing the p38/PMK-1 mitogen-activated protein kinase (MAPK) pathway in vitro and in vivo. The worm mutant lacking the Caenorhabditis elegans homolog BATF3, ZIP-10, exhibited enhanced resistance to PA14 infection, which was completely rescued by transgenic expression of either endogenous zip-10 or mouse or human Batf3 cDNA driven by the worm zip-10 promoter. ZIP-10 expression was inhibited by a microRNA miR-60 that was downregulated upon PA14 infection. Moreover, the level of phosphorylated but not total PMK-1/p38 was attenuated by ZIP-10 and stimulated by miR-60. The human HEK293 cells with Batf3 overexpression or RNA-interference knockdown exhibited a reduction or increase of the cell viability upon Pseudomonas aeruginosa PA14 infection, respectively. The overexpression of either worm ZIP-10 or human BATF3 abolished the activation of p38 and inhibited the expression of antimicrobial peptides and cytokine genes in HEK293 cells. Our findings indicate that the genetic transcriptional program of the evolutionally conserved bZIP transcription factor BATF3/ZIP-10 suppresses innate immunity by attenuating the p38 MAPK signaling activity, which expands our understanding of the pathological mechanisms underlying relevant infectious diseases., (© The Author(s) 2022. Published by Oxford University Press on behalf of The Japanese Society for Immunology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

ABSCISIC ACID-INSENSITIVE3 (ABI3) and ABI5 are 2 crucial transcription factors in abscisic acid (ABA) signaling, and their homeostasis at the protein level plays a decisive role in seed germination and subsequent seedling growth. Here, we found that PLANT U-BOX 8 (PUB8), a U-box E3 ubiquitin ligase, physically interacts with ABI3 and ABI5 and negatively regulates ABA responses during early Arabidopsis (Arabidopsis thaliana) seedling growth. Loss-of-function pub8 mutants were hypersensitive to ABA-inhibited cotyledon greening, while lines overexpressing PUB8 with low levels of ABI5 protein abundance were insensitive to ABA. Genetic analyses showed that ABI3 and ABI5 were required for the ABA-sensitive phenotype of pub8, indicating that PUB8 functions upstream of ABI3 and ABI5 to regulate ABA responses. Biochemical analyses showed that PUB8 can associate with ABI3 and ABI5 for degradation through the ubiquitin-mediated 26S proteasome pathway. Correspondingly, loss-of-function of PUB8 led to enhanced ABI3 and ABI5 stability, while overexpression of PUB8 impaired accumulation of ABI3 and ABI5 in planta. Further phenotypic analysis indicated that PUB8 compromised the function of ABI5 during early seedling growth. Taken together, our results reveal the regulatory role of PUB8 in modulating the early seedling growth by controlling the homeostasis of ABI3 and ABI5., Competing Interests: Conflict of interest statement. No conflict of interest is declared., (© The Author(s) 2023. Published by Oxford University Press on behalf of American Society of Plant Biologists.)

Ferroptosis is triggered by a chain of intracellular labile iron-dependent peroxidation of cell membrane phospholipids. Ferroptosis is important not only as a cause of ischaemic and neurodegenerative diseases but also as a mechanism of cancer suppression, and a better understanding of its regulatory mechanism is required. It has become clear that ferroptosis is finely controlled by two oxidative stress-responsive transcription factors, NRF2 (NF-E2-related factor 2) and BACH1 (BTB and CNC homology 1). NRF2 and BACH1 inhibit and promote ferroptosis, respectively, by activating or suppressing the expression of genes in the major regulatory pathways of ferroptosis: intracellular labile iron metabolism, the GSH (glutathione) -GPX4 (glutathione peroxidase 4) pathway and the FSP1 (ferroptosis suppressor protein 1)-CoQ (coenzyme Q) pathway. In addition to this, NRF2 and BACH1 control ferroptosis through the regulation of lipid metabolism and cell differentiation. This multifaceted regulation of ferroptosis by NRF2 and BACH1 is considered to have been acquired during the evolution of multicellular organisms, allowing the utilization of ferroptosis for maintaining homeostasis, including cancer suppression. In terms of cell-cell interaction, it has been revealed that ferroptosis has the property of propagating to surrounding cells along with lipid peroxidation. The regulation of ferroptosis by NRF2 and BACH1 and the propagation phenomenon could be used to realize anticancer cell therapy in the future. In this review, these points will be summarized and discussed., (© 2022 Federation of European Biochemical Societies.)

T and B cells participate in the development of systemic lupus erythematosus (SLE). BTB and CNC homology 2 (Bach2) is an irreplaceable regulator in the T and B lineages that helps to maintain immune homeostasis. However, the function of Bach2 in the pathogenesis of SLE has not been studied in depth. Flow cytometry and qRT-PCR were used to assess Bach2 levels, bisulfite sequencing PCR was used to measure the methylation level, and silencing by electroporation and stimulation with a cytokine concentration gradient were used to investigate the effect of Bach2 on T cells. Bach2 expression was elevated in the helper T-cell subsets (T follicular helper, Th1, Th2, Th17, and Treg cells) of SLE patients and negatively correlated with disease severity and autoantibody levels. CD4 + T cells from SLE patients had decreased methylation levels in the Bach2 promoter region. Silencing Bach2 in CD4 + T cells induced increases in the CD19 + B-cell count, plasmablasts, and secretion of IgG by prompting the secretion of cytokines. The activation signals CD3/CD28, IL-6, and IL-21 upregulated Bach2 expression in CD4 + T cells. The regulation of Bach2 by cytokines and T-cell activation signals in CD4 + T cells was shown to act on B cells and play a protective role against SLE., (© 2023 Wiley-VCH GmbH.)

Despite unequivocal roles in disease, transcription factors (TFs) remain largely untapped as pharmacologic targets due to the challenges in targeting protein-protein and protein-DNA interactions. Here we report a chemical strategy to generate modular synthetic transcriptional repressors (STRs) derived from the bHLH domain of MAX. Our synthetic approach yields chemically stabilized tertiary domain mimetics that cooperatively bind the MYC/MAX consensus E-box motif with nanomolar affinity, exhibit specificity that is equivalent to or beyond that of full-length TFs and directly compete with MYC/MAX protein for DNA binding. A lead STR directly inhibits MYC binding in cells, downregulates MYC-dependent expression programs at the proteome level and inhibits MYC-dependent cell proliferation. Co-crystallization and structure determination of a STR:E-box DNA complex confirms retention of DNA recognition in a near identical manner as full-length bHLH TFs. We additionally demonstrate structure-blind design of STRs derived from alternative bHLH-TFs, confirming that STRs can be used to develop highly specific mimetics of TFs targeting other gene regulatory elements., (© 2022. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Oomycetes are filamentous microorganisms easily mistaken as fungi but vastly differ in physiology, biochemistry, and genetics. This commonly-held misconception lead to a reduced effectiveness by using conventional fungicides to control oomycetes, thus it demands the identification of novel functional genes as target for precisely design oomycetes-specific microbicide. The present study initially analyzed the available transcriptome data of the model oomycete pathogen, Phytophthora sojae, and constructed an expression matrix of 10,953 genes across the stages of asexual development and host infection. Hierarchical clustering, specificity, and diversity analyses revealed a more pronounced transcriptional plasticity during the stages of asexual development than that in host infection, which drew our attention by particularly focusing on transcripts in asexual development stage to eventually clustered them into 6 phase-specific expression modules. Three of which respectively possessing a serine/threonine phosphatase (PP2C) expressed during the mycelial and sporangium stages, a histidine kinase (HK) expressed during the zoospore and cyst stages, and a bZIP transcription factor (bZIP32) exclusive to the cyst germination stage were selected for down-stream functional validation. In this way, we demonstrated that PP2C, HK, and bZIP32 play significant roles in P. sojae asexual development and virulence. Thus, these findings provide a foundation for further gene functional annotation in oomycetes and crop disease management., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Qiu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

TGA (TGACG-binding) transcription factors, which bind their target DNA through a conserved basic region leucine zipper (bZIP) domain, are vital regulators of gene expression in salicylic acid (SA)-mediated plant immunity. Here, we investigated the role of StTGA2.1, a potato (Solanum tuberosum) TGA lacking the full bZIP, which we named a mini-TGA. Such truncated proteins have been widely assigned as loss-of-function mutants. We, however, confirmed that StTGA2.1 overexpression compensates for SA-deficiency, indicating a distinct mechanism of action compared with model plant species. To understand the underlying mechanisms, we showed that StTGA2.1 can physically interact with StTGA2.2 and StTGA2.3, while its interaction with DNA was not detected. We investigated the changes in transcriptional regulation due to StTGA2.1 overexpression, identifying direct and indirect target genes. Using in planta transactivation assays, we confirmed that StTGA2.1 interacts with StTGA2.3 to activate StPRX07, a member of class III peroxidases (StPRX), which are known to play role in immune response. Finally, via structural modeling and molecular dynamics simulations, we hypothesized that the compact molecular architecture of StTGA2.1 distorts DNA conformation upon heterodimer binding to enable transcriptional activation. This study demonstrates how protein truncation can lead to distinct functions and that such events should be studied carefully in other protein families., Competing Interests: Conflict of interest statement. None declared., (© The Author(s) 2022. Published by Oxford University Press on behalf of American Society of Plant Biologists.)

During innate immune responses, myeloid differentiation primary response 88 (MyD88) functions as a critical signaling adaptor protein integrating stimuli from toll-like receptors (TLR) and the interleukin-1 receptor (IL-1R) family and translates them into specific cellular outcomes. In B cells, somatic mutations in MyD88 trigger oncogenic NF-κB signaling independent of receptor stimulation, which leads to the development of B-cell malignancies. However, the exact molecular mechanisms and downstream signaling targets remain unresolved. We established an inducible system to introduce MyD88 to lymphoma cell lines and performed transcriptomic analysis (RNA-seq) to identify genes differentially expressed by MyD88 bearing the L265P oncogenic mutation. We show that MyD88 L265P activates NF-κB signaling and upregulates genes that might contribute to lymphomagenesis, including CD44, LGALS3 (coding Galectin-3), NFKBIZ (coding IkBƺ), and BATF. Moreover, we demonstrate that CD44 can serve as a marker of the activated B-cell (ABC) subtype of diffuse large B-cell lymphoma (DLBCL) and that CD44 expression is correlated with overall survival in DLBCL patients. Our results shed new light on the downstream outcomes of MyD88 L265P oncogenic signaling that might be involved in cellular transformation and provide novel therapeutical targets.

Maf-family basic motif leucine zipper protein NRL specifies rod photoreceptor cell fate during retinal development and, in concert with homeodomain protein CRX and other regulatory factors, controls the expression of most rod-expressed genes including the visual pigment gene Rhodopsin (Rho). Transcriptional regulatory activity of NRL is modulated by post-translational modifications, especially phosphorylation, and mutations at specific phosphosites can lead to retinal degeneration. During our studies to elucidate NRL-mediated transcriptional regulation, we identified protein kinase CK2 in NRL-enriched complexes bound to Rho promoter-enhancer regions and in NRL-enriched high molecular mass fractions from the bovine retina. The presence of CK2 in NRL complexes was confirmed by co-immunoprecipitation from developing and adult mouse retinal extracts. In vitro kinase assay and bioinformatic analysis indicated phosphorylation of NRL at Ser117 residue by CK2. Co-transfection of Csnk2a1 cDNA encoding murine CK2 with human NRL and CRX reduced the bovine Rho promoter-driven luciferase expression in HEK293 cells and mutagenesis of NRL-Ser117 residue to Ala restored the reporter gene activity. In concordance, overexpression of CK2 in the mouse retina in vivo by electroporation resulted in reduction of Rho promoter-driven DsRed reporter expression as well as the transcript level of many phototransduction genes. Thus, our studies demonstrate that CK2 can phosphorylate Ser117 of NRL. Modulation of NRL activity by CK2 suggests intricate interdependence of transcriptional and signaling pathways in maintaining rod homeostasis., (Published by Oxford University Press 2022.)

Macrophages play essential roles in erythrophagocytosis and iron recycling. β-thalassemia is characterized by a genetic defect in hemoglobin synthesis, which increases the rate of iron recycling. We previously showed that reduced expression of the BTB and CNC homolog 1 (BACH1) gene leads to increased phagocytosis of abnormal RBCs by activated monocytes. However, the mechanisms underlying this abnormal RBC clearance remained unclear. Herein, the spleen and bone marrow cells of β-thalassemic mice were examined for erythrophagocytosis CD markers and iron-recycling genes. Higher expression levels of CD47 and CD163 on RBCs and macrophages, respectively, were observed in β-thalassemic mice than in wild-type cells. The decreased expression of BACH1 caused an increase in Nrf2, Spic, Slc40a1, and HMOX1 expression in splenic red pulp macrophages of thalassemic mice. To investigate BACH1 regulation, a macrophage cell line was transfected with BACH1-siRNA. Decreased BACH1 expression caused an increase in CD163 expression; however, the expression levels were lower when the cells were cultured in media supplemented with β-thalassemia/HbE patient plasma. Additionally, the iron recycling-related genes SPIC, SLC40A1, and HMOX1 were significantly upregulated in BACH1-suppressed macrophages. Our findings provide insights into BACH1 regulation, which plays an important role in erythrophagocytosis and iron recycling in thalassemic macrophages., (© 2022 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.)

The unfolded protein response (UPR) is an important pathway to prevent endoplasmic reticulum (ER) stress in eukaryotic cells. In Saccharomyces cerevisiae, Ire1 is a key regulatory factor required for HAC1 gene splicing for further production of functional Hac1 and activation of UPR gene expression. Autophagy is another mechanism involved in the attenuation of ER stress by ER-phagy, and Atg8 is a core protein in autophagy. Both autophagy and UPR are critical for ER stress response, but whether they act individually or in combination in Candida albicans is unknown. In this study, we explored the interaction between Ire1 and the autophagy protein Atg8 for the ER stress response by constructing the atg8Δ/Δire1Δ/Δ double mutant in the pathogenic fungus C. albicans. Compared to the single mutants atg8Δ/Δ or ire1Δ/Δ, atg8Δ/Δire1Δ/Δ exhibited much higher sensitivity to various ER stress-inducing agents and more severe attenuation of UPR gene expression under ER stress. Further investigations showed that the double mutant had a defect in ER-phagy, which was associated with attenuated vacuolar fusion under ER stress. This study revealed that Ire1 and Atg8 in combination function in the activation of the UPR and ER-phagy to maintain ER homeostasis under ER stress in C. albicans., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2022 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)

Whole-plant transpiration, controlled by plant hydraulics and stomatal movement, is regulated by endogenous and environmental signals, with the light playing a dominant role. Stomatal pore size continuously adjusts to changes in light intensity and quality to ensure optimal CO 2 intake for photosynthesis on the one hand, together with minimal water loss on the other. The link between light and transpiration is well established, but the genetic knowledge of how guard cells perceive those signals to affect stomatal conductance is still somewhat limited. In the current study, we evaluated the role of two central light-responsive transcription factors; a bZIP-family transcription factor ELONGATED HYPOCOTYL5 (HY5) and the basic helix-loop-helix (BHLH) transcription factor PHYTOCHROME INTERACTING FACTOR4 (PIF4), in the regulation of steady-state transpiration. We show that overexpression of PIF4 exclusively in guard cells (GCPIF4) decreases transpiration, and can restrain the high transpiration of the pif4 mutant. Expression of HY5 specifically in guard cells (GCHY5) had the opposite effect of enhancing transpiration rates of WT- Arabidopsis and tobacco plants and of the hy5 mutant in Arabidopsis. In addition, we show that GCHY5 can reverse the low transpiration caused by guard cell overexpression of the sugar sensor HEXOKINASE1 (HXK1, GCHXK), an established low transpiring genotype. Finally, we suggest that the GCHY5 reversion of low transpiration by GCHXK requires the auto-activation of the endogenous HY5 in other tissues. These findings support the existence of an ongoing diurnal regulation of transpiration by the light-responsive transcription factors HY5 and PIF4 in the stomata, which ultimately determine the whole-plant water use efficiency., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The complex retrovirus, human T-cell leukemia virus type 1 (HTLV-1), primarily infects CD4+ T-cells in vivo. Infectious spread within this cell population requires direct contact between virally-infected and target cells. The HTLV-1 accessory protein, HBZ, was recently shown to enhance HTLV-1 infection by activating intracellular adhesion molecule 1 (ICAM-1) expression, which promotes binding of infected cells to target cells and facilitates formation of a virological synapse. In this study we show that HBZ additionally enhances HTLV-1 infection by activating expression of myoferlin (MyoF), which functions in membrane fusion and repair and vesicle transport. Results from ChIP assays and quantitative reverse transcriptase PCR indicate that HBZ forms a complex with c-Jun or JunB at two enhancer sites within the MYOF gene and activates transcription through recruitment of the coactivator p300/CBP. In HTLV-1-infected T-cells, specific inhibition of MyoF using the drug, WJ460, or shRNA-mediated knockdown of MyoF reduced infection efficiency. This effect was associated with a decrease in cell adhesion and an intracellular reduction in the abundance of HTLV-1 envelope (Env) surface unit (SU) and transmembrane domain (TM). Lysosomal protease inhibitors partially restored SU levels in WJ460-treated cells, and SU localization to LAMP-2 sites was increased by MyoF knockdown, suggesting that MyoF restricts SU trafficking to lysosomes for degradation. Consistent with these effects, less SU was associated with cell-free virus particles. Together, these data suggest that MyoF contributes to HTLV-1 infection through modulation of Env trafficking and cell adhesion., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Polakowski et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Multiple lines of evidences have unraveled the emerging role of ferroptosis in the pathophysiological process of acute lung injury (ALI). In this study, we aimed to decipher the role of BACH1 in the onset and progression of ALI with a focus on ferroptosis and elucidated potential molecular mechanism. We observed that BACH1 expression was drastically elevated in BEAS-2B cells upon exposure to LPS. In the functional aspect, BACH1 deletion exerted an anti-inflammatory property, featured by decreased the secretion of several cytokines including TNF-α, IL-1β and IL-6 in the face of LPS challenge. What's more important, BACH1 knockout evidently repressed LPS-triggered oxidative stress damage, as evidenced by reduced reactive oxygen species (ROS) production and malondialdehyde (MDA) generation, accompanied with the elevated the activities of superoxide dismutase (SOD), GSH-Px and CAT. Meanwhile, ablation of BACH1 restrained LPS-elicited ferroptosis, as characterized by decreased iron content and PTGS2 expression, accompanied with increased expression of SLC7A11 and GPX4. In terms of mechanism, Nrf2/HO-1 signaling inhibitor effectively abrogated the beneficial effects of BACH1 inhibition on LPS-stimulated inflammation, oxidative damage and ferroptosis. Taken together, these preceding outcomes strongly illuminated that BACH1 was a novel regulator of LPS-evoked injury through regulation of inflammation response, oxidative stress and ferroptosis via activation Nrf2/HO-1 signaling, indicating that BACH1 may represent as a promising novel therapeutic candidate for ALI treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Selectively targeting leukemia stem cells (LSCs) is a promising approach in treating acute myeloid leukemia (AML), for which identification of such therapeutic targets is critical. Increasing lines of evidence indicate that FBXO22 plays a critical role in solid tumor development and therapy response. However, its potential roles in leukemogenesis remain largely unknown., Methods: We established a mixed lineage leukemia (MLL)-AF9-induced AML model with hematopoietic cell-specific FBXO22 knockout mice to elucidate the role of FBXO22 in AML progression and LSCs regulation, including self-renewal, cell cycle, apoptosis and survival analysis. Immunoprecipitation combined with liquid chromatography-tandem mass spectrometry analysis, Western blotting and rescue experiments were performed to study the mechanisms underlying the oncogenic role of FBXO22., Results: FBXO22 was highly expressed in AML, especially in MLL-rearranged (MLLr) AML. Upon FBXO22 knockdown, human MLLr leukemia cells presented markedly increased apoptosis. Although conditional deletion of Fbxo22 in hematopoietic cells did not significantly affect the function of hematopoietic stem cells, MLL-AF9-induced leukemogenesis was dramatically abrogated upon Fbxo22 deletion, together with remarkably reduced LSCs after serial transplantations. Mechanistically, FBXO22 promoted degradation of BACH1 in MLLr AML cells, and overexpression of BACH1 suppressed MLLr AML progression. In line with this, heterozygous deletion of BACH1 significantly reversed delayed leukemogenesis in Fbxo22-deficient mice., Conclusions: FBXO22 promotes MLLr AML progression by targeting BACH1 and targeting FBXO22 might be an ideal strategy to eradicate LSCs without influencing normal hematopoiesis., (© 2023. The Author(s).)

The carcinogenesis and progression of renal cell carcinoma (RCC), a heterogeneous cancer derived from renal tubular epithelial cells, is closely related to oxidative stress responses (OSRs). Oxidative stress responses participate in various biological processes related to the metabolism and metastatic potential of cancer such as inflammation, epithelial-mesenchymal transition (EMT), and angiogenesis. In this study, we investigated the role of broad complex-tramtrack-bric-a-brac and cap 'n' collar homology 1 (BACH1), a key transcription factor for OSRs, in clear cell RCC (ccRCC) development and prognosis. The poor prognosis and elevation of serum inflammation markers in nephrectomized ccRCC patients were correlated with the intratumor expression of BACH1 accompanied by a downregulation of heme oxygenase-1. BACH1 contributes to the invasion and migration abilities of RCC cell lines without affecting their proliferation in vitro. In contrast, BACH1 contributes to tumor progression in vivo, in relation to OSRs with the activation of EMT-related pathways. BACH1 involvement in other OSR-linked pathways, including inflammatory responses, angiogenesis, and mTOR signaling, was further revealed by RNA sequencing analysis of BACH1-knockdown cells. In conclusion, the crucial role of BACH1 in the pathogenesis and poor prognosis of ccRCC through the promotion of OSRs is suggested., (© 2022 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Light is known to regulate anthocyanin pigment biosynthesis in plants on several levels, but the significance of protein phosphorylation in light-induced anthocyanin accumulation needs further investigation. In this study, we investigated the dynamics of the apple fruit phosphoproteome in response to light, using high-performance liquid chromatography-tandem mass spectrometry analysis. Among the differentially phosphorylated proteins, the bZIP (basic leucine zipper) transcription factor, HY5, which has been identified as an anthocyanin regulator, was rapidly activated by light treatment of the fruit. We hypothesized that phosphorylated MdHY5 may play a role in light-induced anthocyanin accumulation of apple fruit. Protein interaction and phosphorylation assays showed that mitogen-activated protein kinase MdMPK6 directly interacted with, and activated, MdHY5 via phosphorylation under light conditions, thereby increasing its stability. Consistent with this finding, the suppression of the mitogen-activated protein kinase genes MdMPK6 or MdHY5 resulted in an inhibition of anthocyanin accumulation, and further showed that light-induced anthocyanin accumulation is dependent on MdMPK6 kinase activity, and is required for maximum MdHY5 activity. Under light conditions, active MdMPK6 phosphorylated MdHY5 leading to accumulation of phospho-MdHY5, which enhanced the binding of MdHY5 to its target anthocyanin related genes in fruit. Our findings reveal an MdMPK6-MdHY5 phosphorylation pathway in light-induced anthocyanin accumulation, providing new insights into the regulation of light-induced anthocyanin biosynthesis in apple fruit at both the transcriptional and post-translational levels., (© 2022 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.)

The bZIP transcription factors (TFs) govern regulation of development, secondary metabolism, and various stress responses in filamentous fungi. In this work, we carried out genome-wide expression studies employing Illumina RNAseq to understand the roles of the two bZIP transcription factors AtfA and AtfB in Aspergillus nidulans . Comparative analyses of transcriptomes of control, Δ atfA , Δ atfB , and Δ atfA Δ atfB mutant strains were performed. Dependence of a gene on AtfA (AtfB) was decided by its differential downregulation both between the reference and Δ atfA (Δ atfB ) strains and between the Δ atfB (Δ atfA ) and the Δ atfA Δ atfB strains in vegetatively grown cells (mycelia) and asexual spores (conidia) of menadione sodium bisulfite (MSB)-treated or untreated cultures. As AtfA is the primary bZIP TF governing stress-response in A. nidulans , the number of differentially expressed genes for Δ atfA was significantly higher than for Δ atfB in both mycelial and conidial samples, and most of the AtfB-dependent genes showed AtfA dependence, too. Moreover, the low number of genes depending on AtfB but not on AtfA can be a consequence of Δ atfA leading to downregulation of atfB expression. Conidial samples showed much higher abundance of atfA and atfB mRNAs and more AtfA- and AtfB-affected genes than mycelial samples. In the presence of MSB, the number of AtfB- (but not of AtfA-) affected genes decreased markedly, which was accompanied with decreased mRNA levels of atfB in MSB-treated mycelial (reference strain) and conidial (Δ atfA mutant) samples. In mycelia, the overlap between the AtfA-dependent genes in MSB-treated and in untreated samples was low, demonstrating that distinct genes can be under AtfA control under different conditions. Carbohydrate metabolism genes were enriched in the set of AtfA-dependent genes. Among them, AtfA-dependence of glycolytic genes in conidial samples was the most notable. Levels of transcripts of certain secondary metabolitic gene clusters, such as the Emericellamide cluster, also showed AtfA-dependent regulation. Genes encoding catalase and histidine-containing phosphotransfer proteins showed AtfA-dependence under all experimental conditions. There were 23 AtfB-dependent genes that did not depend on AtfA under any of our experimental conditions. These included a putative α-glucosidase ( agdB ), a putative α-amylase, calA, which is involved in early conidial germination, and an alternative oxidase. In summary, in A. nidulans there is a complex interaction between the two bZIP transcription factors, where AtfA plays the primary regulatory role.

Esophageal squamous cell carcinoma (ESCC) is one of the fatal malignancies worldwide. It has an increased propensity to metastasize via lymphogenous routes in an early stage. The prognosis of patients with lymph node metastases (LNM) is often worse than that of patients without metastases. Although several factors have been found to influence metastasis, the mechanisms of preference for specific metastatic routes remain poorly understood. Herein, we provide evidence that the intrinsic hypersensitivity of tumor cells to ferroptosis may proactively drive lymphatic metastasis. Serum autoantibodies associated with LNM of early ESCC were screened using a whole-proteome protein array containing 19 394 human recombinant proteins, and an anti-BACH1 autoantibody was first identified. Pan-cancer analysis of ferroptosis-related genes with preferential lymphatic metastasis and preferential hematogenous metastasis based on The Cancer Genome Atlas data was performed. Only BACH1 showed significant overexpression in tumors with preferential lymphatic metastasis, whereas it was downregulated in most tumors with preferential nonlymphatic metastasis. In addition, it was found that the serum levels of autoantibodies against BACH1 were elevated in early-stage patients with LNM. Interestingly, BACH1 overexpression and ferroptosis induction promoted LNM but inhibited hematogenous metastasis in mouse models. Transcriptomic and lipidomic analyses found that BACH1 repressed SCD1-mediated biosynthesis of monounsaturated fatty acids, especially oleic acid (OA). OA significantly attenuated the ferroptotic phenotypes and reversed the metastatic properties of BACH1-overexpressing cells. OA addition significantly rescued the ferroptotic phenotypes and reversed the metastatic properties of BACH1-overexpressing cells. Importantly, the concentration gradient of OA between primary lesions and the lymph resulted in the chemoattraction of tumor cells to promote invasion, thus facilitating lymphatic metastasis. BACH1-induced ferroptosis drives lymphatic metastasis via the BACH1-SCD1-OA axis. More importantly, this study confirms that ferroptosis is a double-edged sword in tumorigenesis and tumor progression. The clinical application of ferroptosis-associated agents requires a great caution., (© 2023. The Author(s).)