Transcriptional Regulatory Factors Research Articles

An updated compendium and reevaluation of the evidence for nuclear transcription factor occupancy over the mitochondrial genome.

In most eukaryotes, mitochondrial organelles contain their own genome, usually circular, which is the remnant of the genome of the ancestral bacterial endosymbiont that gave rise to modern mitochondria. Mitochondrial genomes are dramatically reduced in their gene content due to the process of endosymbiotic gene transfer to the nucleus; as a result most mitochondrial proteins are encoded in the nucleus and imported into mitochondria. This includes the components of the dedicated mitochondrial transcription and replication systems and regulatory factors, which are entirely distinct from the information processing systems in the nucleus. However, since the 1990s several nuclear transcription factors have been reported to act in mitochondria, and previously we identified 8 human and 3 mouse transcription factors (TFs) with strong localized enrichment over the mitochondrial genome using ChIP-seq (Chromatin Immunoprecipitation) datasets from the second phase of the ENCODE (Encyclopedia of DNA Elements) Project Consortium. Here, we analyze the greatly expanded in the intervening decade ENCODE compendium of TF ChIP-seq datasets (a total of 6,153 ChIP experiments for 942 proteins, of which 763 are sequence-specific TFs) combined with interpretative deep learning models of TF occupancy to create a comprehensive compendium of nuclear TFs that show evidence of association with the mitochondrial genome. We find some evidence for chrM occupancy for 50 nuclear TFs and two other proteins, with bZIP TFs emerging as most likely to be playing a role in mitochondria. However, we also observe that in cases where the same TF has been assayed with multiple antibodies and ChIP protocols, evidence for its chrM occupancy is not always reproducible. In the light of these findings, we discuss the evidential criteria for establishing chrM occupancy and reevaluate the overall compendium of putative mitochondrial-acting nuclear TFs.

Fish oil replacement with different vegetable oils in Onychostoma macrolepis: Effects on fatty acid metabolism based on whole-body fatty acid balance method and genes expression.

To evaluate the fatty acid (FA) metabolism status and possibility as a DHA source of farmed Onychostoma macrolepis, a total of 168 fish (2.03 ± 0.23 g) were fed four diets supplemented with fish oil (FO), linseed oil (LO), soybean oil (SO), and a mixture of LO and SO oil (MO), respectively, for 70 days. Body FA compositions were modified reflecting dietary FAs. Comparing liver and intestine fatty acids with fish fed four diets, the content of ARA in fish fed SO was significantly higher than others (P < 0.05), but showed no difference in muscle. The tissue FA profile showed that the FO-fed group successfully deposited DHA, while the LO-fed group converted ALA to DHA effectively, as well as the liver and intestine EPA was notably highest in the FO group, whereas no difference between the FO and LO group in the muscle. The FA results showed that the DHA contents in the muscle of Onychostoma macrolepis are at a medium-high level compared with several other fish species with the highest aquaculture yield. Correspondingly, in the fish fed diet with LO, SO, and MO, the genes of most FA biosynthesis, transportation, and transcriptional regulation factors were increased in the liver and muscle, but no significant difference was observed in the gene expression of Elovl4b, FATP1, and FABP10 in the muscle. In addition, the enzyme activity involved in PUFA metabolism was higher in fish fed vegetable oil-based diets, corroborating the results of the gene expression. Increased in vivo elongase and desaturase (Δ5, Δ6, and Δ9) activities were recorded in fish fed fish oil-devoid diets, which resulted in the appearance of products associated with elongase and desaturase activities in fish. Besides, as the specific n-3 PUFA synthesis substrate, the dietary supplementation of ALA not only retains most of the nutrition value but also ensures the muscular texture, such as fiber diameter and density. It is concluded that farmed O. macrolepis owns strong n-3 LC-PUFA biosynthetic capacity and high DHA contents so it can be a good DHA source for the population.

Human T-cell lymphotropic virus type 1 (HTLV-1) grip on T-cells: investigating the viral tapestry of activation

IntroductionHuman T-cell Lymphotropic virus type 1 (HTLV-1) belongs to retroviridae which is connected to two major diseases, including HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and Adult T-cell leukemia/lymphoma (ATLL). This study aims to investigate the mRNA expressions of key proteins correlated to T-cell activation in asymptomatic carriers (ACs) HTLV-1 infected patients, shedding light on early molecular events and T-cell activation following HTLV-1 infection.Material and MethodsThe study involved 40 participants, including 20 ACs and 20 healthy subjects. Blood samples were collected, ELISA assessment for screening and confirmation with PCR for Trans-activating transcriptional regulatory protein (Tax) and HTLV-1 basic leucine zipper factor (HBZ) of the HTLV-1 were done. mRNA expressions of C-terminal Src kinase (CSK), Glycogen Synthase Kinase-3 Beta (GSK3β), Mitogen-Activated Protein Kinase 14 (MAP3K14 or NIK), Phospholipase C Gamma-1 (PLCG1), Protein Tyrosine Phosphatase non-Receptor Type 6 (PTPN6) and Mitogen-Activated Protein Kinase Kinase Kinase-7 (SLP-76) and Mitogen-Activated Protein Kinase14 (MAP3K7 or TAK1) were assayed using RT-qPCR. Statistical analyses were performed using PRISM and SPSS software.ResultsWhile there were no significant upregulation in CSK and PTPN6 in ACs compared to healthy individuals, expression levels of GSK3β, MAP3K14, PLCG1, SLP-76, and TAK1 were significantly higher in ACs compared to healthy subjects which directly contributes to T-cell activation in the HTLV-1 ACs.ConclusionHTLV-1 infection induces differential mRNA expressions in key proteins associated with T-cell activation. mRNAs related to T-cell activation showed significant upregulation compared to PTPN6 and CSK which contributed to T-cell regulation. Understanding these early molecular events in ACs may provide potential markers for disease progression and identify therapeutic targets for controlling viral replication and mitigating associated diseases. The study contributes novel insights to the limited literature on T-cell activation and HTLV-1 pathogenesis.

Tannic acid inhibits Escherichia coli biofilm formation and underlying molecular mechanisms: Biofilm regulator CsgD

Biofilms often engender persistent infections, heightened antibiotic resistance, and the recurrence of infections. Therefor, infections related to bacterial biofilms are often chronic and pose challenges in terms of treatment. The main transcription regulatory factor, CsgD, activates csgABC-encoded curli to participate in the composition of extracellular matrix, which is an important skeleton for biofilm development in enterobacteriaceae. In our previous study, a wide range of natural bioactive compounds that exhibit strong affinity to CsgD were screened and identified via molecular docking. Tannic acid (TA) was subsequently chosen, based on its potent biofilm inhibition effect as observed in crystal violet staining. Therefore, the aim of this study was to investigate the specific effects of TA on the biofilm formation of clinically isolated Escherichia coli (E. coli). Results demonstrated a significant inhibition of E. coli Ec032 biofilm formation by TA, while not substantially affecting the biofilm of the ΔcsgD strain. Moreover, deletion of the csgD gene led to a reduction in Ec032 biofilm formation, alongside diminished bacterial motility and curli synthesis inhibition. Transcriptomic analysis and RT-qPCR revealed that TA repressed genes associated with the csg operon and other biofilm-related genes. In conclusion, our results suggest that CsgD is one of the key targets for TA to inhibit E. coli biofilm formation. This work preliminarily elucidates the molecular mechanisms of TA inhibiting E. coli biofilm formation, which could provide a lead structure for the development of future antibiofilm drugs.

Engineering Fatty Acid Biosynthesis in Microalgae: Recent Progress and Perspectives.

Microalgal lipids hold significant potential for the production of biodiesel and dietary supplements. To enhance their cost-effectiveness and commercial competitiveness, it is imperative to improve microalgal lipid productivity. Metabolic engineering that targets the key enzymes of the fatty acid synthesis pathway, along with transcription factor engineering, are effective strategies for improving lipid productivity in microalgae. This review provides a summary of the advancements made in the past 5 years in engineering the fatty acid biosynthetic pathway in eukaryotic microalgae. Furthermore, this review offers insights into transcriptional regulatory mechanisms and transcription factor engineering aimed at enhancing lipid production in eukaryotic microalgae. Finally, the review discusses the challenges and future perspectives associated with utilizing microalgae for the efficient production of lipids.

Inhibitory potential of Syzygium aromaticum against Fusarium oxysporum f. sp. lycopersici: In-vitro analysis and molecular docking studies

The antifungal potential of the extract of cloves (Syzygium aromaticum) was investigated in this study. The crude extracts of cloves and n-hexane, chloroform and n-butanol fractions were prepared. The antifungal activity of obtained fractions was studied at various concentrations ranging from 1.5 to 200.00 µg/mL. Thiophanate methyl (TM) was used as +ve control in this study. The fractions including methanolic, n-hexane, n-butanol, and chloroform significantly inhibited the growth of Fusarium oxysporum f.sp. lycopersici (FOL) ranging from 93.8 to 100 % when used at 200 µg/mL. The chloroform fraction showed 6.25 µg/mL MIC as compared to TM with 64 µg/mL MIC. GC/MS analysis showed that the chloroform fraction contained Eugenol, Phenol, 2,2′-methylenebis[6-(1,1-dimethylethyl)-4-methyl, 2,4-Di‑tert-butylphenol, n-Hexadecanoic acid, Phenol, and 2‑methoxy-4-(2-propenyl)- acetate. The findings of in-vitro antifungal analysis were further supported by molecular docking studies. Two virulence proteins of FOL i.e., global transcription regulator (SGE1) and DNA binding transcription factor (STE12) were docked with identified phytocompounds in the chloroform fraction by GC/MS analysis. Both of the receptors showed maximum binding affinities with 2-[2-(4-Phenyl-piperidin-1-yl)-ethyl]-isoindole-1,3‑dione (PED) (-12.054 kcal/mol) and 3,5-di‑tert-Butyl-4-hydroxyphenylpropionic acid (BHP) (-13.327 kcal/mol) respectively with strong hydrophilic/phobic interactions with active pocket residues. In conclusion, the chloroform fraction of S. aromaticum can be used to manage FOL.

Improving the production of carbamoyltobramycin by an industrial Streptoalloteichus tenebrarius through metabolic engineering

Tobramycin is an essential and extensively used broad-spectrum aminoglycoside antibiotic obtained through alkaline hydrolysis of carbamoyltobramycin, one of the fermentation products of Streptoalloteichus tenebrarius. To simplify the composition of fermentation products from industrial strain, the main byproduct apramycin was blocked by gene disruption and constructed a mutant mainly producing carbamoyltobramycin. The generation of antibiotics is significantly affected by the secondary metabolism of actinomycetes which could be controlled by modifying the pathway-specific regulatory proteins within the cluster. Within the tobramycin biosynthesis cluster, a transcriptional regulatory factor TobR belonging to the Lrp/AsnC family was identified. Based on the sequence and structural characteristics, tobR might encode a pathway-specific transcriptional regulatory factor during biosynthesis. Knockout and overexpression strains of tobR were constructed to investigate its role in carbamoyltobramycin production. Results showed that knockout of TobR increased carbamoyltobramycin biosynthesis by 22.35%, whereas its overexpression decreased carbamoyltobramycin production by 10.23%. In vitro electrophoretic mobility shift assay (EMSA) experiments confirmed that TobR interacts with DNA at the adjacent tobO promoter position. Strains overexpressing tobO with ermEp* promoter exhibited 36.36% increase, and tobO with kasOp* promoter exhibited 22.84% increase in carbamoyltobramycin titer. When the overexpressing of tobO and the knockout of tobR were combined, the production of carbamoyltobramycin was further enhanced. In the shake-flask fermentation, the titer reached 3.76 g/L, which was 42.42% higher than that of starting strain. Understanding the role of Lrp/AsnC family transcription regulators would be useful for other antibiotic biosynthesis in other actinomycetes.Key points• The transcriptional regulator TobR belonging to the Lrp/AsnC family was identified. • An oxygenase TobO was identified within the tobramycin biosynthesis cluster.• TobO and TobR have significant effects on the synthesis of carbamoyltobramycin.

SIRT1 and ZNF350 as novel biomarkers for osteoporosis: a bioinformatics analysis and experimental validation.

Osteoporosis (OP) is characterized by bone mass decrease and bone tissue microarchitectural deterioration in bone tissue. This study identified potential biomarkers for early diagnosis of OP and elucidated the mechanism of OP. Gene expression profiles were downloaded from Gene Expression Omnibus (GEO) for the GSE56814 dataset. A gene co-expression network was constructed using weighted gene co-expression network analysis (WGCNA) to identify key modules associated with healthy and OP samples. Functional enrichment analysis was conducted using the R clusterProfiler package for modules to construct the transcriptional regulatory factor networks. We used the "ggpubr" package in R to screen for differentially expressed genes between the two samples. Gene set variation analysis (GSVA) was employed to further validate hub gene expression levels between normal and OP samples using RT-PCR and immunofluorescence to evaluate the potential biological changes in various samples. There was a distinction between the normal and OP conditions based on the preserved significant module. A total of 100 genes with the highest MM scores were considered key genes. Functional enrichment analysis suggested that the top 10 biological processes, cellular component and molecular functions were enriched. The Toll-like receptor signaling pathway, TNF signaling pathway, PI3K-Akt signaling pathway, osteoclast differentiation, JAK-STAT signaling pathway, and chemokine signaling pathway were identified by Kyoto Encyclopedia of Genes and Genomes pathway analysis. SIRT1 and ZNF350 were identified by Wilcoxon algorithm as hub differentially expressed transcriptional regulatory factors that promote OP progression by affecting oxidative phosphorylation, apoptosis, PI3K-Akt-mTOR signaling, and p53 pathway. According to RT-PCR and immunostaining results, SIRT1 and ZNF350 levels were significantly higher in OP samples than in normal samples. SIRT1 and ZNF350 are important transcriptional regulatory factors for the pathogenesis of OP and may be novel biomarkers for OP treatment.

The novel candidate gene Grb10 regulates the growth performance of Guizhou white goats

Growth factor receptor binding protein 10 (Grb10) regulates muscle growth but its function in goats is not well studied. This study examined the relationship between Grb10 gene polymorphism and growth traits in Guizhou white goats. Further, the effect of promoter polymorphism on Grb10 transcription was analyzed via a dual-luciferase assay. Quantitative reverse transcription-polymerase chain reaction analysis showed that the expression level of the Grb10 gene was the highest in the longissimus dorsi muscle (P < 0.01) and the lowest in the spleen. Moreover, sequencing results showed that the Grb10 gene had five single nucleotide polymorphisms. The association analysis showed that g.–246 C > T, g.72323 T > C, and g.178634 A > G loci were significantly associated with growth traits (P < 0.05). Linkage disequilibrium analysis of each locus showed that g.72323 T > C and g.72814 T > A loci had the strongest linkage (r2 = 0.482, D' = 0.73). Furthermore, according to an analysis conducted using TFDB4 software, it was predicted that a mutation in the promoter region of the g.–246 C > T locus resulted in the absence of four transcriptional regulatory factors. The results of dual-luciferase reporter assay further demonstrated that mutation of the g.–246 C > T locus reduced the transcriptional activity of the promoter region of the Grb10 gene. These findings suggest that Grb10 gene polymorphism could affect growth traits in goats.

IFI35 regulates non-canonical NF-κB signaling to maintain glioblastoma stem cells and recruit tumor-associated macrophages.

Glioblastoma (GBM) is the most aggressive malignant primary brain tumor characterized by a highly heterogeneous and immunosuppressive tumor microenvironment (TME). The symbiotic interactions between glioblastoma stem cells (GSCs) and tumor-associated macrophages (TAM) in the TME are critical for tumor progression. Here, we identified that IFI35, a transcriptional regulatory factor, plays both cell-intrinsic and cell-extrinsic roles in maintaining GSCs and the immunosuppressive TME. IFI35 induced non-canonical NF-kB signaling through proteasomal processing of p105 to the DNA-binding transcription factor p50, which heterodimerizes with RELB (RELB/p50), and activated cell chemotaxis in a cell-autonomous manner. Further, IFI35 induced recruitment and maintenance of M2-like TAMs in TME in a paracrine manner. Targeting IFI35 effectively suppressed in vivo tumor growth and prolonged survival of orthotopic xenograft-bearing mice. Collectively, these findings reveal the tumor-promoting functions of IFI35 and suggest that targeting IFI35 or its downstream effectors may provide effective approaches to improve GBM treatment.

Silencing TRIM29 Sensitizes Non-small Cell Lung Cancer Cells to Anlotinib by Promoting Apoptosis via Binding RAD50.

Previous studies have proposed that the transcriptional regulatory factor tripartite motif containing 29 (TRIM29) is involved in carcinogenesis via binding with nucleic acid. TRIM29 is confirmed to be highly expressed when the cancer cells acquire therapy-resistant properties. We noticed that TRIM29 levels were significantly increased in anlotinib-resistant NCIH1975 (NCI-H1975/AR) cells via mining data information from gene expression omnibus (GEO) gene microarray (GSE142031; log2 fold change > 1, p &#60; 0.05). Our study aimed to investigate the function of TRIM29 on the resistance to anlotinib in non-small cell lung cancer (NSCLC) cells, including NCI-H1975 and A549 cells. Real-time RT-PCR and western blot were used to detect TRIM29 expression in anlotinib- resistant NSCLC (NSCLC/AR) cells. Apoptosis were determined through flow cytometry, acridine orange/ethidium bromide staining as well as western blot. ELISA was used to measure the content of C-X3-C motif chemokine ligand 1. Co-Immunoprecipitation assay was performed to verify the interaction between TRIM29 and RAD50 double-strand break repair protein (RAD50). TRIM29 expression was shown to be elevated in the cytoplasm and nucleus of NSCLC/ AR cells compared to normal NSCLC cells. Next, we demonstrated that TRIM29 knockdown facilitated apoptosis and enhanced the sensitivity to anlotinib in NSCLC/AR cells. Based on the refined results citing from the database BioGRID, it was proved that TRIM29 interacted with RAD50. Herein, RAD50 overexpression diminished the pro-apoptotic effect induced by silencing TRIM29 in anlotinib-resistant A549 (A549/AR) cells. Finally, we concluded that the increased sensitivity to anlotinib in NSCLC/AR cells was achieved by knocking down TRIM29, besides, the positive effects of TRIM29 knockdown were attributed to the promotion of apoptosis via binding to RAD50 in NSCLC/AR cell nucleus. Therefore, TRIM29 might become a potential target for overcoming anlotinib resistance in NSCLC treatment.

Key chromatin regulator-related genes associated with the risk of coronary artery disease regulate the expression of HCFC1, RNF8, TNP1 and SET

Chromatin regulators are indispensable upstream epigenetic regulators.The emergence and progression of atherosclerosis has been demonstrated to be influenced by smooth muscle-related chromatin regulators, such as ZEB2 and MAFF. However, specific chromatin regulators and their possible roles have not been clarified. Information was gathered from 51 patients diagnosed with coronary artery disease (CAD) and 50 individuals in good health from the GEO database. 440 genes were identified as having differential expression across the two datasets, and these genes were linked to cellular reactions. Enrichment of pathways related to histone modification and transcriptional regulatory factors was observed in GO and KEGG analyses. Four machine learning models (RF, SVM, GLM, and XGB) were developed using the expression profiles of 440 chromatin-associated genes in the CAD cohort to pinpoint genes with significant diagnostic potential. After evaluating residuals, root mean square errors, receiver operating characteristic curves, and immune-infiltration, four key genes (HCFC1, RNF8, TNP1, and SET) were identified. Gene expression in different blood vessel levels in atherosclerotic plaques in a mouse model of coronary artery disease showed significant variations. The gene expression levels in macrophages aligned with clinical data from the GEO database as expected. This discovery is crucial for future analysis and the prediction of drug and miRNA targets. In conclusion, we found that the four hub genes are important in the mechanism of CAD. These findings provide new ideas for the study of potential epigenetic predictive markers and therapeutic targets to be used in determining a treatment strategy for CAD.

The involvement of interferon regulatory factor 8 in regulating the proliferation of haemocytes in oyster Crassostrea gigas

Interferon regulatory factor 8 (IRF8) is an important transcriptional regulatory factor involving in multiple biological process, such as the antiviral immune response, immune cell proliferation and differentiation. In the present study, the involvement of a previously identified IRF8 homologue (CgIRF8) in regulating haemocyte proliferation of oyster were further investigated. CgIRF8 mRNA transcripts were detectable in all the stages of C. gigas larvae with the highest level in D-veliger (1.76-fold of that in zygote, p < 0.05). Its mRNA transcripts were also detected in all the three haemocyte subpopulations of adult oysters with the highest expression in granulocytes (2.79-fold of that in agranulocytes, p < 0.01). After LPS stimulation, the mRNA transcripts of CgIRF8 in haemocytes significantly increased at 12 h and 48 h, which were 2.04-fold and 1.65-fold (p < 0.05) of that in control group, respectively. Meanwhile, the abundance of CgIRF8 protein in the haemocytes increased significantly at 12 h after LPS stimulation (1.71-fold of that in seawater, p < 0.05). The immunofluorescence assay and Western blot showed that LPS stimulation induced an obvious nucleus translocation of CgIRF8 protein in haemocytes. After the expression of CgIRF8 was inhibited by the injection of CgIRF8 siRNA, the percentage of EdU positive haemocytes, the proportion of granulocytes, and the mRNA expression levels of CgGATA and CgSCL all declined significantly at 12 h after LPS stimulation, which was 0.64-fold (p < 0.05), 0.7-fold (p < 0.05), 0.31-fold and 0.54-fold (p < 0.001) of that in the NC group, respectively. While the expression level of cell proliferation-related protein CgCDK2, CgCDC6, CgCDC45 and CgPCNA were significantly increased (1.99-fold, and 2.41-fold, 3.76-fold and 4.79-fold compared to that in the NC group respectively, p < 0.001). Dual luciferase reporter assay demonstrated that CgIRF8 was able to activate the CgGATA promoter in HEK293T cells after transfection of CgGATA and CgIRF8. These results collectively indicated that CgIRF8 promoted haemocyte proliferation by regulating the expression of CgGATA and other related genes in the immune response of oyster.

NPM3 as an Unfavorable Prognostic Biomarker Involved in Oncogenic Pathways of Lung Adenocarcinoma via MYC Translational Activation.

The nucleoplasmin/nucleophosmin (NPM) family was previously regarded as a critical regulator during disease development, and its mediation in carcinogenesis has achieved intensive attention recently. However, the clinical importance and functional mechanism of NPM3 in lung adenocarcinoma (LUAD) have not been reported yet. This study aimed to investigate the role and clinical significance of NPM3 in the development and progression of LUAD, including the underlying mechanisms. The expression of NPM3 in pan-cancer was analyzed via GEPIA. The effect of NPM3 on prognosis was analyzed by the Kaplan-Meier plotter and the PrognoScan database. In vitro, cell transfection, RT-qPCR, CCK-8 assay, and wound healing assay were employed to examine the role of NPM3 in A549 and H1299 cells. Gene set enrichment analysis (GSEA) was performed using the R software package to analyze the tumor hallmark pathway and KEGG pathway of NPM3. The transcription factors of NPM3 were predicted based on the ChIP-Atlas database. Dual-luciferase reporter assay was applied to verify the transcriptional regulatory factor of the NPM3 promoter region. The NPM3 expression was found to be markedly higher in the LUAD tumor group than the normal group and to be positively correlated with poor prognosis, tumor stages, and radiation therapy. In vitro, the knockdown of NPM3 greatly inhibited the proliferation and migration of A549 and H1299 cells. Mechanistically, GSEA predicted that NPM3 activated the oncogenic pathways. Further, the NPM3 expression was found to be positively correlated with cell cycle, DNA replication, G2M checkpoint, HYPOXIA, MTORC1 signaling, glycolysis, and MYC targets. Besides, MYC targeted the promoter region of NPM3 and contributed to the enhanced expression of NPM3 in LUAD. The overexpression of NPM3 is an unfavorable prognostic biomarker participating in oncogenic pathways of LUAD via MYC translational activation and it contributes to tumor progression. Thus, NPM3 could be a novel target for LUAD therapy.

Infectious bursal disease virus VP5 triggers host shutoff in a transcription-dependent manner.

Viruses have evolved intricate mechanisms to evade host antiviral responses and exploit cellular resources by manipulating the expression profile of host genes. During infection, viruses encode proteins with shutoff activity to globally inhibit host protein synthesis, which is an effective strategy for immune evasion. In this study, compelling evidence shows that infectious bursal disease virus (IBDV) infection triggers the suppression of host protein synthesis. Furthermore, using both in vitro and in vivo viral infection models, we have identified that IBDV specifically impedes the transcription of host genes via the shutoff activity of viral VP5, simultaneously conferring advantages to IBDV infection in these circumstances. The proposed mechanism suggests that VP5 competitively binds to RanBP1, disrupting the RanGDP/GTP gradient. This disruption interferes with cellular nucleocytoplasmic transport, impairing the nuclear import of proteins bearing nuclear localization signals. The nuclear transport of pivotal transcriptional regulatory factors, such as p65 and IFN regulatory factor 7, is also compromised, leading to the inhibition of pro-inflammatory cytokines and interferon expression. This newly discovered strategy employed by IBDV enables them to manipulate host gene expression, providing novel insights into how viruses evade host immune responses and establish infections.IMPORTANCEViruses manipulate host processes at various levels to regulate or evade both innate and adaptive immune responses, promoting self-survival and efficient transmission. The "host shutoff," a global suppression of host gene expression mediated by various viruses, is considered a critical mechanism for evading immunity. In this study, we have validated the presence of host shutoff during infectious bursal disease virus (IBDV) infection and additionally uncovered that the viral protein VP5 plays a pivotal role in inhibiting the overall synthesis of host proteins, including cytokines, through a transcription-dependent pathway. VP5 competitively binds with RanBP1, leading to disruption of the Ran protein cycle and consequently interfering with nucleocytoplasmic transport, which ultimately results in the suppression of host gene transcription. These findings unveil a novel strategy employed by IBDV to evade host innate immunity and rapidly establish infection. This study also suggests a novel supplement to understanding the pathway through which viruses inhibit host protein synthesis.

ZNF471 Interacts with BANP to Reduce Tumour Malignancy by Inactivating PI3K/AKT/mTOR Signalling but is Frequently Silenced by Aberrant Promoter Methylation in Renal Cell Carcinoma.

Background: Renal cell carcinoma (RCC) is one of the most common malignant tumours of the urinary system. However, the aetiology and pathogenesis of RCC remain unclear. The C2H2 zinc finger protein (ZNF) family is the largest transcriptional regulatory factor family found in mammals, and Krüppel-associated box domain-containing zinc finger proteins (KRAB-ZFPs) constitute the largest subfamily of the C2H2 zinc finger protein family and play an important role in the occurrence and development of tumours. The aim of this study was to explore the role of abnormal methylation of ZNF471 in the development of renal carcinoma. Methods: In this study, we first used the TCGA and EWAS Data Hub databases to analyse the expression and methylation levels of ZNF471 in renal carcinoma tissues and adjacent normal tissues. Second, we collected samples of renal cancer and adjacent normal tissues at Peking University First Hospital to investigate the expression and methylation level of ZNF471 in renal cancer tissues and the relationships between these levels and the clinicopathological features and prognosis of patients with renal cancer. Next, we investigated the effects of ZNF471 on the proliferation, metastasis, cell cycle progression, and apoptosis of renal cell carcinoma cells by cell biology experiments. Finally, we elucidated the underlying molecular mechanisms of ZNF471 in renal cell carcinoma by transcriptome sequencing, bioinformatics analysis and molecular biology experiments. Results: The expression of ZNF471 in renal carcinoma tissues and cell lines was significantly lower than that in adjacent normal tissues and cell lines due to abnormal promoter CpG methylation. Furthermore, the expression of ZNF471 in renal carcinoma tissues was negatively correlated with tumour stage and grade in patients with renal carcinoma. The results of the cell biology experiments showed that ZNF471 could significantly inhibit the proliferation, migration and cell cycle progression of renal cell carcinoma cells and promote apoptosis in these cells. In addition, ZNF471 could interact with BANP and suppress the malignant phenotype of RCC by inactivating the PI3K/AKT/mTOR signalling pathway. Conclusions: As an important tumour suppressor, ZNF471 can interact with BANP in renal cancer cells and inhibit the activation of the PI3K/AKT/mTOR signalling pathway, thereby inhibiting the occurrence and development of renal cancer.

Regulating Pathways of Bacillus pumilus Adamalysin-like Metalloendopeptidase Expression.

The minor secreted proteinase of B. pumilus 3-19 MprBp classified as the unique bacillary adamalysin-like enzyme of the metzincin clan. The functional role of this metalloproteinase in the bacilli cells is not clear. Analysis of the regulatory region of the mprBp gene showed the presence of potential binding sites to the transcription regulatory factors Spo0A (sporulation) and DegU (biodegradation). The study of mprBp activity in mutant strains of B. subtilis defective in regulatory proteins of the Spo- and Deg-systems showed that the mprBp gene is partially controlled by the Deg-system of signal transduction and independent from the Spo-system.

Development of a whole-cell biosensor for detection of pyocyanin based on a transcriptional regulation factor

The infection caused by multidrug-resistant bacteria Pseudomonas aeruginosa is a huge challenge in biomedical treatment, and early identification of pathogen P. aeruginosa has guiding significance for patient treatment. Pyocyanin (PYO) is a virulence factor uniquely secreted by the P. aeruginosa, thus valuable information about the presence of P. aeruginosa and the patient's infection progression status can be revealed through detection of PYO (the biomarker of P. aeruginosa infection) in clinical samples. Herein, we developed a unique and convenient whole-cell biosensor for PYO based on a transcriptional regulator (BrlR) responding to PYO. The input signal of this biosensor is the concentration of PYO, and the output signal is the intensity of fluorescent protein. The characteristic curve of the biosensor fitted well with the hill equation (R2 =0.9911), and the limit of detection (LOD, S/N = 3) of PYO estimated from the whole-cell biosensor calibration curve was 1.3 μM, lower than the concentration range currently used for clinical detection and required only about 1/4 of current detection time. Moreover, this biosensor exhibits good reliability, repeatability, and reproducibility in detecting PYO concentration of biological samples. The biosensor we developed here can be used to detect PYO content in infected patients conveniently, sensitively, and inexpensively, paving the way for early warning of severe P. aeruginosa infections.

Microbiome and plant cell transformation trigger insect gall induction in cassava.

Several specialised insects can manipulate normal plant development to induce a highly organised structure known as a gall, which represents one of the most complex interactions between insects and plants. Thus far, the mechanism for insect-induced plant galls has remained elusive. To study the induction mechanism of insect galls, we selected the gall induced by Iatrophobia brasiliensis (Diptera: Cecidomyiidae) in cassava (Euphorbiaceae: Manihot esculenta Crantz) as our model. PCR-based molecular markers and deep metagenomic sequencing data were employed to analyse the gall microbiome and to test the hypothesis that gall cells are genetically transformed by insect vectored bacteria. A shotgun sequencing discrimination approach was implemented to selectively discriminate between foreign DNA and the reference host plant genome. Several known candidate insertion sequences were identified, the most significant being DNA sequences found in bacterial genes related to the transcription regulatory factor CadR, cadmium-transporting ATPase encoded by the cadA gene, nitrate transport permease protein (nrtB gene), and arsenical pump ATPase (arsA gene). In addition, a DNA fragment associated with ubiquitin-like gene E2 was identified as a potential accessory genetic element involved in gall induction mechanism. Furthermore, our results suggest that the increased quality and rapid development of gall tissue are mostly driven by microbiome enrichment and the acquisition of critical endophytes. An initial gall-like structure was experimentally obtained in M. esculenta cultured tissues through inoculation assays using a Rhodococcus bacterial strain that originated from the inducing insect, which we related to the gall induction process. We provide evidence that the modification of the endophytic microbiome and the genetic transformation of plant cells in M. esculenta are two essential requirements for insect-induced gall formation. Based on these findings and having observed the same potential DNA marker in galls from other plant species (ubiquitin-like gene E2), we speculate that bacterially mediated genetic transformation of plant cells may represent a more widespread gall induction mechanism found in nature.

Highly Similar Tetramerization Domains from the p53 Protein of Different Mammalian Species Possess Varying Biophysical, Functional and Structural Properties

The p53 protein is a transcriptional regulatory factor and many of its functions require that it forms a tetrameric structure. Although the tetramerization domain of mammalian p53 proteins (p53TD) share significant sequence similarities, it was recently shown that the tree shrew p53TD is considerably more thermostable than the human p53TD. To determine whether other mammalian species display differences in this domain, we used biophysical, functional, and structural studies to compare the properties of the p53TDs from six mammalian model organisms (human, tree shrew, guinea pig, Chinese hamster, sheep, and opossum). The results indicate that the p53TD from the opossum and tree shrew are significantly more stable than the human p53TD, and there is a correlation between the thermostability of the p53TDs and their ability to activate transcription. Structural analysis of the tree shrew and opossum p53TDs indicated that amino acid substitutions within two distinct regions of their p53TDs can dramatically alter hydrophobic packing of the tetramer, and in particular substitutions at positions corresponding to F341 and Q354 of the human p53TD. Together, the results suggest that subtle changes in the sequence of the p53TD can dramatically alter the stability, and potentially lead to important changes in the functional activity, of the p53 protein.