Glucose regulation of adipose tissue browning by CBP/p300- and HDAC3-mediated reversible acetylation of CREBZF.

Glucose is required for generating heat during cold-induced nonshivering thermogenesis in adipose tissue, but the regulatory mechanism is largely unknown. CREBZF has emerged as a critical mechanism for metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as nonalcoholic fatty liver disease (NAFLD). We investigated the roles of CREBZF in the control of thermogenesis and energy metabolism. Glucose induces CREBZF in human white adipose tissue (WAT) and inguinal WAT (iWAT) in mice. Lys208 acetylation modulated by transacetylase CREB-binding protein/p300 and deacetylase HDAC3 is required for glucose-induced reduction of proteasomal degradation and augmentation of protein stability of CREBZF. Glucose induces rectal temperature and thermogenesis in white adipose of control mice, which is further potentiated in adipose-specific CREBZF knockout (CREBZF FKO) mice. During cold exposure, CREBZF FKO mice display enhanced thermogenic gene expression, browning of iWAT, and adaptive thermogenesis. CREBZF associates with PGC-1α to repress thermogenic gene expression. Expression levels of CREBZF are negatively correlated with UCP1 in human adipose tissues and increased in WAT of obese ob/ob mice, which may underscore the potential role of CREBZF in the development of compromised thermogenic capability under hyperglycemic conditions. Our results reveal an important mechanism of glucose sensing and thermogenic inactivation through reversible acetylation.

Identification of BACH1-IT2-miR-4786-Siglec-15 immune suppressive axis in bladder cancer.

The sialic acid binding Ig like lectin 15 (Siglec-15) was previously identified as tumor immune suppressor gene in some human cancers with elusive molecular mechanism to be elucidated. The continuous focus on both clinical and basic biology of bladder cancer leads us to characterize aberrant abundance of BACH1-IT2 associating with stabilization of Siglec-15, which eventually contributes to local immune suppressive microenvironment and therefore tumor advance. This effect was evidently mediated by miR-4786-5p. BACH1-IT2 functions in this scenario as microRNA sponge, and competitively conceals miR-4786 and up-regulates cancer cell surface Siglec-15. The BACH1-IT2-miR-4786-Siglec-15 axis significantly influences activation of immune cell co-culture. In summary, our data highlights the critical involvements of BACH1-IT2 and miR-4786 in immune evasion in bladder cancer, which hints the potential for both therapeutic and prognostic exploitation.

Identification of bZIP Transcription Factors That Regulate the Development of Leaf Epidermal Cells in Arabidopsis thaliana by Single-Cell RNA Sequencing.

Epidermal cells are the main avenue for signal and material exchange between plants and the environment. Leaf epidermal cells primarily include pavement cells, guard cells, and trichome cells. The development and distribution of different epidermal cells are tightly regulated by a complex transcriptional regulatory network mediated by phytohormones, including jasmonic acid, and transcription factors. How the fate of leaf epidermal cells is determined, however, is still largely unknown due to the diversity of cell types and the complexity of their regulation. Here, we characterized the transcriptional profiles of epidermal cells in 3-day-old true leaves of Arabidopsis thaliana using single-cell RNA sequencing. We identified two genes encoding BASIC LEUCINE-ZIPPER (bZIP) transcription factors, namely bZIP25 and bZIP53, which are highly expressed in pavement cells and early-stage meristemoid cells. Densities of pavement cells and trichome cells were found to increase and decrease, respectively, in bzip25 and bzip53 mutants, compared with wild-type plants. This trend was more pronounced in the presence of jasmonic acid, suggesting that these transcription factors regulate the development of trichome cells and pavement cells in response to jasmonic acid.

FAK mediates hypoxia-induced pulmonary artery smooth muscle cell proliferation by modulating mitochondrial transcription termination factor 1/cyclin D1.

This study aimed to investigate the mechanism of FAK-dependent hypoxia-induced proliferation on human pulmonary artery smooth muscle cells (HPASMCs). Primary HPASMCs were isolated and cultured in vitro under normal and hypoxia conditions to assess cell proliferation with cell counting kit-8. FAK and mitochondrial transcription termination factor 1 (mTERF1) were silenced with siRNA, mRNA, and protein levels of FAK, mTERF1, and cyclin D1 were determined. HPASMC proliferation increased under hypoxia compared to normal conditions. Knocking down FAK or mTERF1 with siRNA led to decreased cell proliferation under both normal and hypoxia conditions. FAK knockdown led to the reduction of both mTERF1 and cyclin D1 expressions under the hypoxia conditions, whereas mTERF1 knockdown led to the downregulation of cyclin D1 expression but not FAK expression under the same condition. However, under normal conditions, knocking down either FAK or mTERF1 had no impact on cyclin D1 expression. These results suggested that FAK may regulate the mTERF1/cyclin D1 signaling pathway to modulate cell proliferation in hypoxia.

Cdc73 is a major regulator of apoptosis-inducing factor 1 expression in Saccharomyces cerevisiae via H3K36 methylation.

Apoptosis-inducing factor 1 (AIF1) overexpression is intimately linked to the sensitivity of yeast cells towards hydrogen peroxide or acetic acid. Therefore, studying the mechanism of AIF1 regulation in the cell would provide a significant understanding of the factors guiding yeast apoptosis. In this report, we show the time-dependent induction of AIF1 under hydrogen peroxide stress. Additionally, we find that AIF1 expression in response to hydrogen peroxide is mediated by two transcription factors, Yap5 (DNA binding) and Cdc73 (non-DNA binding). Furthermore, substituting the H3K36 residue with another amino acid significantly abrogates AIF1 expression. However, substituting the lysine (K) in H3K4 or H3K79 with alanine (A) does not affect AIF1 expression level under hydrogen peroxide stress. Altogether, reduced AIF1 expression in cdc73Δ is plausibly due to reduced H3K36me3 levels in the cells.

Light-dependent expression and accumulation of miR408-encoded peptide, miPEP408, is regulated by HY5 in Arabidopsis.

Recent studies propose that primary transcripts of miRNAs (pri-miRNAs) contain small Open Reading Frames (ORFs) capable of encoding miRNA-encoded peptides (miPEPs). These miPEPs can function as transcriptional regulators for their corresponding pri-miRNAs, ultimately enhancing mature miRNA accumulation. Notably, pri-miR408 encodes the functional peptide miPEP408, regulating expression of miR408 and its target genes, providing plant tolerance to stresses. While miPEPs are crucial regulators, the factors governing them are have not been studied in detail. Here, we explored the light-dependent regulation of miPEP408 in Arabidopsis. Expression analysis during dark-light transitions revealed light-induced transcription and accumulation of the miPEP408. As the promoter of miR408 contains cis-acting elements responsible for binding to the bZIP-type transcription factor ELONGATED HYPOCOTYL5 (HY5), known for light-mediated regulation in plants, we studied its involvement in the regulation of miR408. Analysis of HY5 mutant (hy5-215), complemented line (HY5OX/hy5), and CONSTITUTIVE PHOTOMORPHOGENIC 1 mutant (cop1-4) plants supported HY5's positive regulation of miPEP408. Grafting and GUS assays further suggested the role of HY5 as a shoot-root mobile signal inducing light-dependent miPEP408 expression. This study underscores the regulatory impact of light on small peptides, exemplified by miPEP408, mediated by the key transcription factor HY5.

Identification roles of NFE2L3 in digestive system cancers.

BACKGROUND: Morbidity and mortality rates of Digestive System Cancers (DSC) continue to pose human lives and health. Nuclear factor erythroid 2-like protein 3 (NFE2L3) is aberrantly expressed in DSC. This study aimed to explore the clinical value and underlying mechanisms of NFE2L3 as a novel biomarker in DSC. METHODS: We utilized data from databases and clinical gastric cancer specimens to validate the aberrant expression level of NFE2L3 and further assessed the clinical value of NFE2L3. To investigate the potential molecular mechanism of NFE2L3, we analyzed the correlation of NFE2L3 with immune molecular mechanisms, constructed PPI network, performed GO analysis and KEGG analysis, and finally explored the biological function of NFE2L3 in gastric cancer cells. RESULTS: NFE2L3 expression is up-regulated in DSC and has both prognostic and diagnostic value. NFE2L3 correlates with various immune mechanisms, PPI network suggests proteins interacting with NFE2L3, GSEA analysis suggests potential molecular mechanisms for NFE2L3 to play a role in cancer promotion, and in vitro cellular experiments also confirmed the effect of NFE2L3 on the biological function of gastric cancer cells. CONCLUSION: Our study confirms the aberrant expression and molecular mechanisms of NFE2L3 in DSC, indicating that NFE2L3 could serve as a novel biomarker for diagnosis and prognosis of DSC.

Vulnerability to APOBEC3G linked to the pathogenicity of deltaretroviruses.

Human retroviruses are derived from simian ones through cross-species transmission. These retroviruses are associated with little pathogenicity in their natural hosts, but in humans, HIV causes AIDS, and human T-cell leukemia virus type 1 (HTLV-1) induces adult T-cell leukemia-lymphoma (ATL). We analyzed the proviral sequences of HTLV-1, HTLV-2, and simian T-cell leukemia virus type 1 (STLV-1) from Japanese macaques (Macaca fuscata) and found that APOBEC3G (A3G) frequently generates G-to-A mutations in the HTLV-1 provirus, whereas such mutations are rare in the HTLV-2 and STLV-1 proviruses. Therefore, we investigated the mechanism of how HTLV-2 is resistant to human A3G (hA3G). HTLV-1, HTLV-2, and STLV-1 encode the so-called antisense proteins, HTLV-1 bZIP factor (HBZ), Antisense protein of HTLV-2 (APH-2), and STLV-1 bZIP factor (SBZ), respectively. APH-2 efficiently inhibits the deaminase activity of both hA3G and simian A3G (sA3G). HBZ and SBZ strongly suppress sA3G activity but only weakly inhibit hA3G, suggesting that HTLV-1 is incompletely adapted to humans. Unexpectedly, hA3G augments the activation of the transforming growth factor (TGF)-ß/Smad pathway by HBZ, and this activation is associated with ATL cell proliferation by up-regulating BATF3/IRF4 and MYC. In contrast, the combination of APH-2 and hA3G, or the combination of SBZ and sA3G, does not enhance the TGF-ß/Smad pathway. Thus, HTLV-1 is vulnerable to hA3G but utilizes it to promote the proliferation of infected cells via the activation of the TGF-ß/Smad pathway. Antisense factors in each virus, differently adapted to control host cellular functions through A3G, seem to dictate the pathogenesis.

Concise review: The heterogenous roles of BATF3 in cancer oncogenesis and dendritic cells and T cells differentiation and function considering the importance of BATF3-dependent dendritic cells.

The transcription factor, known as basic leucine zipper ATF-like 3 (BATF3), is a crucial contributor to the development of conventional type 1 dendritic cells (cDC1), which is definitely required for priming CD8 + T cell-mediated immunity against intracellular pathogens and malignancies. In this respect, BATF3-dependent cDC1 can bring about immunological tolerance, an autoimmune response, graft immunity, and defense against infectious agents such as viruses, microbes, parasites, and fungi. Moreover, the important function of cDC1 in stimulating CD8 + T cells creates an excellent opportunity to develop a highly effective target for vaccination against intracellular pathogens and diseases. BATF3 has been clarified to control the development of CD8α+ and CD103+ DCs. The presence of BATF3-dependent cDC1 in the tumor microenvironment (TME) reinforces immunosurveillance and improves immunotherapy approaches, which can be beneficial for cancer immunotherapy. Additionally, BATF3 acts as a transcriptional inhibitor of Treg development by decreasing the expression of the transcription factor FOXP3. However, when overexpressed in CD8 + T cells, it can enhance their survival and facilitate their transition to a memory state. BATF3 induces Th9 cell differentiation by binding to the IL-9 promoter through a BATF3/IRF4 complex. One of the latest research findings is the oncogenic function of BATF3, which has been approved and illustrated in several biological processes of proliferation and invasion.

Structural basis for specific DNA sequence recognition by the transcription factor NFIL3.

The CCAAT/enhancer-binding proteins (C/EBPs) constitute a family of pivotal transcription factors involved in tissue development, cellular function, proliferation, and differentiation. NFIL3, as one of them, plays an important role in regulating immune cell differentiation, circadian clock system, and neural regeneration, yet its specific DNA recognition mechanism remains enigmatic. In this study, we showed by the ITC binding experiments that NFIL3 prefers to bind to the TTACGTAA DNA motif. Our structural studies revealed that the α-helical NFIL3 bZIP domain dimerizes through its leucine zipper region, and binds to DNA via its basic region. The two basic regions of the NFIL3 bZIP dimer were pushed apart upon binding to DNA, facilitating the snug accommodation of the two basic regions within the major grooves of the DNA. Remarkably, our binding and structural data also revealed that both NFIL3 and C/EBPα/ß demonstrate a shared preference for the TTACGTAA sequence. Furthermore, our study revealed that disease-associated mutations within the NFIL3 bZIP domain result in either reduction or complete disruption of its DNA binding ability. These discoveries not only provide valuable insights into the DNA binding mechanisms of NFIL3 but also elucidate the causal role of NFIL3 mutations in disease pathogenesis.

The bZIP transcription factor MpbZIP9 regulates anthocyanin biosynthesis in Malus 'Pinkspire' fruit.

Malus 'Pinkspire' is regulated by abscisic acid (ABA), which results in a red colour, but the regulatory relationship between ABA and anthocyanin synthesis has not been determined. The key factors affecting the colour change of M. 'Pinkspire' peel were investigated during the periods of significant colour changes during fruit ripening. The results showed that the transcription factor MpbZIP9 associated with ABA was screened by transcriptomic analysis. MpbZIP9 expression was consistent with the trend of structural genes expression for anthocyanin synthesis in the peel during fruit ripening, as well as with changes in the content of ABA, which is a positive regulator. A yeast one-hybrid assay showed that MpbZIP9 can directly bind to the promoter of MpF3'H. Dual luciferase reporter gene assays and GUS staining experiments showed that MpbZIP9 significantly activate MpF3'H expression. In addition, overexpression of the MpbZIP9 significantly enhanced anthocyanin accumulation and the expression of genes involved in anthocyanin synthesis. In contrast, virus-induced silencing of the MpbZIP9 significantly reduced the expression of structural genes involved in anthocyanin synthesis. These results suggest that the MpbZIP9 transcription factor can regulate the synthesis of peel anthocyanin and is a positive regulator that promotes anthocyanin biosynthesis by activating MpF3'H expression.

EuTGA1, a bZIP transcription factor, positively regulates EuFPS1 expression in Eucommia ulmoides.

Eucommia ulmoides (E. ulmoides) is widely cultivated and exhibits remarkable adaptability in China. It is the most promising rubber source plant in the temperate zone. E. ulmoides gum (EUG) is a trans-polyisoprene with a unique "rubber-plastic duality", and is widely used in advanced materials and biomedical fields. The transcription of Farnesyl pyrophosphate synthase (FPS), the rate-limiting enzyme of EUG biosynthesis, is controlled by regulatory mechanisms that remain poorly elucidated. In this research, 12 TGA transcription factors (TFs) in E. ulmoides were identified. Promoter prediction results revealed that the EuFPS1 promoter had binding sites for EuTGAs. Subsequently, the EuTGA1 was obtained by screening the E. ulmoides cDNA library using the EuFPS1 promoter as a bait. The individual yeast one­hybrid and dual-luciferase assays confirmed that in the tobacco plant, EuTGA1 interacted with the EuFPS1 promoter, resulting in a more than threefold increase in the activity of the EuFPS1. Subcellular localization study further revealed that EuTGA1 is localized in the nucleus and acts as a TF to regulate EuFPS1 expression. In addition, qRT-PCR analysis demonstrated that the expression trend of EuFPS1 and EuTGA1 was the same at different time of the year. Notably, low temperature and MeJA treatments down-regulated EuTGA1 expression. Additionally, the transient transformation of EuTGA1 enhanced NtFPS1 expression in tobacco plants. Overall, this study identified a TF that interacted with EuFPS1 promoter to positively regulate EuFPS1 expression. The findings of this study provide a theoretical basis for further research on the expression regulation of EuFPS1.

Regulation of metal homoeostasis by two F-group bZIP transcription factors bZIP48 and bZIP50 in rice.

Zinc (Zn) deficiency not only impairs plant growth and development but also has negative effects on human health. Rice (Oryza Sativa L.) is a staple food for over half of the global population, yet the regulation of Zn deficiency response in rice remains largely unknown. In this study, we provide evidence that two F-group bZIP transcription factors, OsbZIP48/50, play a crucial role in Zn deficiency response. Mutations in OsbZIP48/50 result in impaired growth and reduced Zn/Fe/Cu content under Zn deficiency conditions. The N-terminus of OsbZIP48/OsbZIP50 contains two Zn sensor motifs (ZSMs), deletion or mutation of these ZSMs leads to increased nuclear localization. Both OsbZIP48 and OsbZIP50 exhibit transcriptional activation activity, and the upregulation of 1117 genes involved in metal uptake and other processes by Zn deficiency is diminished in the OsbZIP48/50 double mutant. Both OsbZIP48 and OsbZIP50 bind to the promoter of OsZIP10 and activate the ZDRE cis-element. Amino acid substitution mutation of the ZSM domain of OsbZIP48 in OsbZIP50 mutant background increases the content of Zn/Fe/Cu in brown rice seeds and leaves. Therefore, this study demonstrates that OsbZIP48/50 play a crucial role in regulating metal homoeostasis and identifies their downstream genes involved in the Zn deficiency response in rice.

Integrated genetic analysis of diabetic complications: Bioinformatics insights into foot ulcers, neuropathy and peripheral artery disease.

Diabetic foot ulcers (DFU), diabetic peripheral neuropathy (DPN) and peripheral arterial disease (PAD) are common complications of diabetes mellitus, while diabetic peripheral neuropathy and peripheral arterial disease contribute to the pathogenesis of diabetic foot ulcers, and the pathogenic mechanisms between these three diseases still need further investigation. The keywords 'diabetic foot ulcer', 'diabetic peripheral neuropathy' and 'atherosclerosis' were used to search for related gene sets in the GEO database. Differentially expressed genes (DEGs) were screened and analysed for GO, KEGG and enrichR functional enrichment. Potential three disease biomarkers were identified by SVM-SVM-RFE and LASSO regression analysis. The results were also validated using external datasets and discriminability was measured by area under the ROC curve (AUC). Finally, biomarkers and co-upregulated genes were analysed through the GSEA and Attie Laboratories diabetes databases. A total of 11 shared genes (KRT16, CD24, SAMD9L, SRGAP2, FGL2, GPR34, DDIT4, NFE2L3, FBLN5, ANXA3 and CPA3), two biomarkers (SAMD9L and FGL2) and one co-upregulated gene (CD24) were screened. GO and KEGG pathway analysis of DEGs, enrichr enrichment analysis of shared differential genes and GSEA analysis of biomarkers showed that these significant genes were mainly focused on vasoregulatory, inflammatory-oxidative stress and immunomodulatory pathways. In this study, we used bioinformatics to investigate the intrinsic relationship and potential mechanisms of three common lower extremity complications of diabetes and identified two pivotal genes using the LASSO model and the SVM-RFE algorithm, which will further help clinicians to understand the relationship between diabetic complications, improve the diagnosis and treatment of diabetic foot problems and help doctors to identify the potential risk factors of diabetic foot.

ABA functions in low phosphate-induced anthocyanin accumulation through the transcription factor ABI5 in Arabidopsis.

KEY MESSAGE: ABI5 functions in ABA-mediated anthocyanin accumulation in plant response to low phosphate. Low phosphate (LP)-induced anthocyanin biosynthesis and accumulation play an important role in plant adaptive response to phosphate starvation conditions. However, whether and how the stress phytohormone abscisic acid (ABA) participates in LP-induced anthocyanin accumulation remain elusive. Here, we report that ABA is required for LP-induced anthocyanin accumulation in Arabidopsis thaliana. Disrupting ABA DEFICIENT2 (ABA2), a key ABA-biosynthetic gene, or BETA-GLUCOSIDASE1 (BG1), a major gene implicated in converting conjugated ABA to active ABA, significantly impairs LP-induced anthocyanin accumulation, as LP-induced expression of the anthocyanin-biosynthetic genes Chalcone Synthase (CHS) is dampened in the aba2 and bg1 mutant. In addition, LP-induced anthocyanin accumulation is defective in the mutants of ABA signaling pathway, including ABA receptors, ABA Insensitive2, and the transcription factors ABA Insensitive5 (ABI5), suggesting a role of ABI5 in ABA-mediated upregulation of anthocyanin-biosynthetic genes in plant response to LP. Indeed, LP-induced expression of CHS is repressed in the abi5-7 mutant but further promoted in the ABI5-overexpressing plants compared to the wild-type. Moreover, ABI5 can bind to and transcriptionally activate CHS, and the defectiveness of LP-induced anthocyanin accumulation in abi5-7 can be restored by overexpressing CHS. Collectively, our findings illustrates that ABI5 functions in ABA-mediated LP-induced anthocyanin accumulation in Arabidopsis.

Genome-wide analysis of bZIP gene family members in Pleurotus ostreatus, and potential roles of PobZIP3 in development and the heat stress response.

The basic leucine zipper (bZIP) transcription factor (TF) is widespread among eukaryotes and serves different roles in fungal processes including nutrient utilization, growth, stress responses and development. The oyster mushroom (Pleurotus ostreatus) is an important and widely cultivated edible mushroom worldwide; nevertheless, reports are lacking on the identification or function of bZIP gene family members in P. ostreatus. Herein, 11 bZIPs on 6 P. ostreatus chromosomes were systematically identified, which were classified into 3 types according to their protein sequences. Phylogenetic analysis of PobZIPs with other fungal bZIPs indicated that PobZIPs may have differentiated late. Cis-regulatory element analysis revealed that at least one type of stress-response-related element was present on each bZIP promoter. RNA-seq and RT-qPCR analyses revealed that bZIP expression patterns were altered under heat stress and different developmental stages. We combined results from GST-Pull-down, EMSA and yeast two-hybrid assays to screen a key heat stress-responsive candidate gene PobZIP3. PobZIP3 overexpression in P. ostreatus enhanced tolerance to high temperature and cultivation assays revealed that PobZIP3 positively regulates the development of P. ostreatus. RNA-seq analysis showed that PobZIP3 plays a role in glucose metabolism pathways, antioxidant enzyme activity and sexual reproduction. These results may support future functional studies of oyster mushroom bZIP TFs.

Root-specific photoreception directs early root development by HY5-regulated ROS balance.

Root development is tightly controlled by light, and the response is thought to depend on signal transmission from the shoot. Here, we show that the root apical meristem perceives light independently from aboveground organs to activate the light-regulated transcription factor ELONGATED HYPOCOTYL5 (HY5). The ROS balance between H2O2 and superoxide anion in the root is disturbed under darkness with increased H2O2. We demonstrate that root-derived HY5 directly activates PER6 expression to eliminate H2O2. Moreover, HY5 directly represses UPBEAT1, a known inhibitor of peroxidases, to release the expression of PERs, partially contributing to the light control of ROS balance in the root. Our results reveal an unexpected ability in roots with specific photoreception and provide a mechanistic framework for the HY5-mediated interaction between light and ROS signaling in early root development.

S1 basic leucine zipper transcription factors shape plant architecture by controlling C/N partitioning to apical and lateral organs.

Plants tightly control growth of their lateral organs, which led to the concept of apical dominance. However, outgrowth of the dormant lateral primordia is sensitive to the plant's nutritional status, resulting in an immense plasticity in plant architecture. While the impact of hormonal regulation on apical dominance is well characterized, the prime importance of sugar signaling to unleash lateral organ formation has just recently emerged. Here, we aimed to identify transcriptional regulators, which control the trade-off between growth of apical versus lateral organs. Making use of locally inducible gain-of-function as well as single and higher-order loss-of-function approaches of the sugar-responsive S1-basic-leucine-zipper (S1-bZIP) transcription factors, we disclosed their largely redundant function in establishing apical growth dominance. Consistently, comprehensive phenotypical and analytical studies of S1-bZIP mutants show a clear shift of sugar and organic nitrogen (N) allocation from apical to lateral organs, coinciding with strong lateral organ outgrowth. Tissue-specific transcriptomics reveal specific clade III SWEET sugar transporters, crucial for long-distance sugar transport to apical sinks and the glutaminase GLUTAMINE AMIDO-TRANSFERASE 1_2.1, involved in N homeostasis, as direct S1-bZIP targets, linking the architectural and metabolic mutant phenotypes to downstream gene regulation. Based on these results, we propose that S1-bZIPs control carbohydrate (C) partitioning from source leaves to apical organs and tune systemic N supply to restrict lateral organ formation by C/N depletion. Knowledge of the underlying mechanisms controlling plant C/N partitioning is of pivotal importance for breeding strategies to generate plants with desired architectural and nutritional characteristics.

Molecular identification and functional characterization of an environmental stress responsive glutaredoxin gene ROXY1 in Quercus glauca.

Quercus glauca is a valuable natural resource with both economic and ecological values. It is one of the dominant forest tree species widely distributed in Southern China. As a perennial broadleaf plant, Q. glauca inevitably encounters numerous stresses from environment. Glutaredoxins (GRXs) are a kind of small oxidoreductases that play an important role in response to oxidative stress. CC-type GRXs also known as ROXYs are specific to land plants. In this study, we isolated a CC-type GRX gene, QgROXY1, from Q. glauca. Expression of QgROXY1 is induced by a variety of environmental stimuli. QgROXY1 protein localizes to both cytoplasm and nucleus; whereas the nucleus localized QgROXY1 could physically interact with the basic region/leucine zipper motif (bZIP) transcription factor AtTGA2 from Arabidopsis thaliana. Transgenic A. thaliana ectopically expressing QgROXY1 is hypersensitive to exogenously applied salicylic acid. Induction of plant defense gene is significantly impaired in QgROXY1 transgenic plants that results in enhanced susceptibility to infection of Botrytis cinerea pathogen, indicating the evolutionary conserved function among ROXY homologs in weedy and woody plants. This is the first described function for the ROXYs in tree plants. Through this case study, we demonstrated the feasibility and efficacy of molecular technology applied to characterization of gene function in tree species.

Exosomal miR-361-3p promotes the viability of breast cancer cells by targeting ETV7 and BATF2 to upregulate the PAI-1/ERK pathway.

BACKGROUND: Malignant progression is the major cause of poor prognosis in breast cancer (BC) patients. Plasma exosomal miRNAs have been reported to be involved in tumor progression, but their roles in BC remain unclear. METHODS: We performed plasma exosomal miRNA sequencing on 45 individuals, including healthy controls and nonmetastatic and metastatic BC patients. We examined the correlation between miRNA expression in tumor tissues and plasma exosomes in BC patients by qRT‒PCR. The effects of exosomal miR-361-3p on BC cells were determined by CellTiter-Glo, migration and wound healing assays. The target genes of miR-361-3p and downstream pathways were explored by dual-luciferase reporter assay, RNA knockdown, rescue experiments, and western blotting. We utilized murine xenograft model to further assess the impact of plasma exosomal miR-361-3p on the malignant progression of BC. RESULTS: We found that the expression level of plasma exosomal miR-361-3p gradually increased with malignant progression in BC patients, and the expression of miR-361-3p in plasma exosomes and BC tissues was positively correlated. Consistently, exosomal miR-361-3p enhanced the migration and proliferation of two BC cell lines, MDA-MB-231 and SK-BR-3. Furthermore, our data showed that miR-361-3p inhibited two novel target genes, ETV7 and BATF2, to activate the PAI-1/ERK pathway, leading to increased BC cell viability. Finally, the consistency of the in vivo experimental results supported that elevated plasma exosomal miR-361-3p promote the malignant progression of BC. CONCLUSIONS: We found for the first time that plasma exosomal miR-361-3p was associated with malignant progression in BC patients. Mechanistically, exosomal miR-361-3p can enhance the migration and proliferation of BC cells by targeting the ETV7 and BATF2/PAI-1/ERK pathways. Our data suggest that plasma exosomal miR-361-3p has the potential to serve as a biomarker for predicting malignant progression in BC patients.