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Although antiviral drugs can effectively inhibit hepatitis B virus (HBV) replication, the maintenance of chronic inflammation in the liver is still considered to be an important cause for the progression of HBV-related liver disease to liver fibrosis and advanced liver disease. As an endogenous inhibitory receptor of IL-1R and TLR signaling pathways, single immunoglobulin interleukin-1-related receptor (SIGIRR) has been proven to reduce inflammation in tissues to maintain system homeostasis. However, the relationship between SIGIRR expression and HBV replication and inflammatory pathway activation in hepatocytes remains unclear. In this study, hepatitis B virus X protein (HBx) upregulated MyD88 in liver cells, promoting NF-κB signaling and inflammatory factor production with LPS treatment, and the cell supernatant accelerated the activation and collagen secretion of hepatic stellate cells. However, SIGIRR overexpression suppressed HBx-mediated MyD88/NF-κB inflammatory signaling activation and inflammatory cytokine production induced by LPS in hepatocytes and HBV replication hepatocytes. Although we did not find any effect of SIGIRR on HBV replication in vitro, this study investigated the role of SIGIRR in blocking the proinflammatory function of HBx, which may provide a new idea for the treatment of chronic hepatitis B., 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 © 2024 Elsevier B.V. All rights reserved.)

As an essential transcriptional activator, PDX1 plays a crucial role in pancreatic development and β-cell function. Mutations in the PDX1 gene may lead to type 4 maturity-onset diabetes of the young (MODY4) and neonatal diabetes mellitus. However, the precise mechanisms underlying MODY4 remain elusive due to the paucity of clinical samples and pronounced differences in pancreatic architecture and genomic composition between humans and existing animal models. In this study, three PDX1 -mutant cynomolgus macaques were generated using CRISPR/Cas9 technology, all of which succumbed shortly postpartum, exhibiting pancreatic agenesis. Notably, one tri-allelic PDX1 -mutant cynomolgus macaque (designated as M4) developed a pancreas, whereas the two mono-allelic PDX1- mutant cynomolgus macaques displayed no anatomical evidence of pancreatic formation. RNA sequencing of the M4 pancreas revealed substantial molecular changes in both endocrine and exocrine functions, indicating developmental delay and PDX1 haploinsufficiency. A marked change in m6A methylation was identified in the M4 pancreas, confirmed through cultured PDX1 -mutant islet organoids. Notably, overexpression of the m6A modulator METTL3 restored function in heterozygous PDX1 -mutant islet organoids. This study highlights a novel role of m6A methylation modification in the progression of MODY4 and provides valuable molecular insights for preclinical research.

Aging is an inevitable law of the process of life during which many physiological functions change. Brain aging is an important mechanism in the occurrence and development of degenerative diseases of the central nervous system. β-Hydroxybutyrate (BHBA) is a water-soluble, endogenous small-molecule ketone that can cross the blood-brain barrier and induce neuroprotective effects. This study aimed to investigate the effects of BHBA on D-galactose (D-gal) induced aging in mice and its underlying mechanisms using in vitro and in vivo experiments. These results indicated that D-gal-induced senescence, oxidative stress, and inflammatory responses were inhibited by BHBA, and autophagy was promoted by BHBA. Mechanistically, we explored the role of metastasis-associated antigen-1 (MTA1) in D-gal-induced damaged in HT22 cells using small interfering RNA (siRNA). The results demonstrated that the expression of MTA1 was significantly increased by BHBA, which attenuated D-gal-induced aging, oxidative stress, and inflammatory responses, and promoted autophagy through the upregulation of MTA1. In conclusion, MTA1 may be a novel target for treating aging caused by neurological damage. BHBA improves brain aging by activating the MTA1 pathway., 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 © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Dental pulp stem cells (DPSCs) have acquired noteworthy attention for their application in treating ischemic diseases and facilitating tissue regeneration. However, the host's immune response following allogenic DPSC transplantation often handicaps the long-term survival of transplanted cells, thereby limiting the application of DPSCs in cell therapy. This study aims to investigate whether genetic modification can alleviate the immunogenicity of DPSCs., Methods: Beta 2-microglobulin (B2M) and the class II histocompatibility complex transactivator (CIITA) were individually knocked down in DPSCs by lentiviral particles encoding short hairpin (sh) RNAs. The self-renewal capacity and pluripotency of DPSCs-shB2M (B2M silenced DPSCs) and DPSCs-shCIITA (CIITA silenced DPSCs) were evaluated by CCK8 and differentiation assays including osteogenesis, adipogenesis, and neurogenesis. The expression of HLA-I and HLA-II in DPSCs-shB2M and DPSCs-shCIITA after IFN-γ treatment were analyzed by western blotting, immunofluorescence, and flow cytometry. The function of genetically modified cells was assessed by leukocyte-mediated cytotoxicity and T-cell proliferation assays., Results: Western blotting, immunofluorescence, and flow cytometry revealed that DPSCs-shB2M and DPSCs-shCIITA exhibited impaired IFN-γ inducible HLA-I and HLA-II expression. There were no significant differences in the self-renewal capacity and pluripotency among DPSCs-shB2M, DPSCs-shCIITA, and control groups (p > 0.05). Lower leukocyte-mediated cytotoxicity and higher cell survival rates were found in DPSCs-shB2M and DPSCs-shCIITA groups compared to the control (p < 0.05). T cell proliferation was significantly inhibited in both DPSCs-shB2M and DPSCs-shCIITA groups (p < 0.05)., Conclusion: Genetic knockdown of B2M or CIITA in DPSCs substantially reduced their immunogenicity without compromising their stemness, thereby broadening the clinical application of DPSCs in cell therapy and tissue regeneration., Competing Interests: Declarations Ethics approval and consent to participate The collection of human blood in this study has been approved by the Institutional Review Board of the University of Hong Kong/Hospital Authority Hong Kong West Cluster in September 2022, IRB ref. Number: UW 22–611, titled “Beta-2 microglobulin and CIITA knockdown decrease allogeneic immune rejection and improve the survival of dental pulp stem cells”. All blood donors provided written informed consent for participation in this study and the use of the sample. Consent for publication Not applicable. Competing interests The authors declare that they have no competing interests., (© 2024. The Author(s).)

Human genetics analysis has identified many noncoding SNPs associated with diabetic traits, but whether and how these variants contribute to diabetes is largely unknown. Here, we focus on a noncoding variant, rs6048205, and report that the risk-G variant impairs the generation of PDX1+/NKX6-1+ pancreatic progenitor cells and further results in the abnormal decrease of functional β cells during pancreatic differentiation. Mechanistically, this risk-G variant greatly enhances RXRA binding and over-activates FOXA2 transcription, specifically in the pancreatic progenitor stage, which in turn represses NKX6-1 expression. Consistently, inducible FOXA2 overexpression could phenocopy the differentiation defect. More importantly, mice carrying risk-G exhibit abnormal pancreatic islet architecture and are more sensitive to streptozotocin or a high-fat diet to develop into diabetes eventually. This study not only identifies a causal noncoding variant in diabetes susceptibility but also dissects the underlying gain-of-function mechanism by recruiting stage-specific factors., Competing Interests: Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

In a retrospective analysis of clinical data from 587 DLBCL (diffuse large B-cell lymphoma) patients in China, 13.8% of cases were associated with HBV (hepatitis B virus) infection, leading to distinct clinical features and poorer prognosis. Moreover, HBV infection has a more pronounced impact on the survival of the GCB (germinal center B-cell-like) type DLBCL patients compared to the ABC (activated B-cell-like) type. In this study, we found that the expression of LncRNA MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) was downregulated in the HBV-infected GCB-type DLBCL patients, and the HBV core protein (HBX) directly inhibited the MALAT1 expression in DLBCL cells. Notably, the overexpression of HBX could attenuate the Erastin-induced ferroptosis in the GCB-type DLBCLs, while MALAT1 re-expression restored sensitivity in the HBX-overexpressing DLBCLs in vitro and in vivo. Mechanistically, MALAT1 competitively hindered SFPQ (splicing factor proline and glutamine-rich) from effectively splicing the pre-mRNA of SLC7A11 (solute carrier family 7 member 11), due to a shared TTGGTCT motif, which impeded the SLC7A11 pre-mRNA maturation and hence diminished its negative regulation on ferroptosis. Together, our study identified HBX's role in inhibiting MALAT1 expression, promoting SFPQ-mediated splicing of SLC7A11 pre-mRNA, and reducing the GCB-type DLBCL sensitivity to Erastin-induced ferroptosis. Combined with the recent studies that ferroptosis may be involved in the occurrence and development of DLBCL, these findings explain our clinical data analysis that DLBCL patients with low expression of MALAT1 have poorer prognosis and shorter overall survival, and provide a valuable therapeutic target for the HBV-infected GCB-type DLBCL patients., Competing Interests: Competing interests The authors declare no competing interests. Ethics approval and consent to participate All procedures involving experimental animals were conducted in strict accordance with the guidelines and regulations of the Experimental Animal Center at Tongji University. All animal experiments were performed following a protocol approved by the Animal Protection and Use Committee of Tongji University (Approval Number: TJAB04524105). The paraffin-embedded cancer patient samples used in this study were obtained from the affiliated Changhai Hospital of the Navy Medical University. Informed consent was obtained from all participants, and the study was approved by the Ethics Committee of the affiliated Changhai Hospital of the Navy Medical University., (© 2024. The Author(s).)

Activation domains (ADs) within transcription factors (TFs) induce gene expression by recruiting coactivators such as the Mediator complex. Coactivators lack DNA binding domains (DBDs) and are assumed to passively follow their recruiting TFs. This is supported by direct AD-coactivator interactions seen in vitro but has not yet been tested in living cells. To examine that, we targeted two Med15-recruiting ADs to a range of budding yeast promoters through fusion with different DBDs. The DBD-AD fusions localized to hundreds of genomic sites but recruited Med15 and induced transcription in only a subset of bound promoters, characterized by a fuzzy-nucleosome architecture. Direct DBD-Med15 fusions shifted DBD localization towards fuzzy-nucleosome promoters, including promoters devoid of the endogenous Mediator. We propose that Med15, and perhaps other coactivators, possess inherent promoter preference and thus actively contribute to the selection of TF-induced genes., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.)

The epigenetic landscape plays a critical role in cancer progression, yet its therapeutic potential remains underexplored. Glucocorticoids are essential components of treatments for lymphoid cancers, but resistance, driven in part by epigenetic changes at glucocorticoid-response elements, poses a major challenge to effective therapies. Here we show that glucocorticoid treatment induces distinct patterns of chromosomal organization in glucocorticoid-sensitive and resistant acute lymphoblastic leukemia xenograft models. These glucocorticoid-response elements are primed by the pioneer transcription factor PU.1, which interacts with the glucocorticoid receptor. Eviction of PU.1 promotes receptor binding, increasing the expression of genes involved in apoptosis and facilitating a stronger therapeutic response. Treatment with a PU.1 inhibitor enhances glucocorticoid sensitivity, demonstrating the clinical potential of targeting this pathway. This study uncovers a mechanism involving PU.1 and the glucocorticoid receptor, linking transcription factor activity with drug response, and suggesting potential therapeutic strategies for overcoming resistance., (© 2024. The Author(s).)

Staphylococcus aureus can cause outbreaks and becomes multi-drug resistant through gene mutations and acquiring resistance genes. However, why S. aureus easily adapts to hospital environments, promoting resistance and recurrent infections, remains unknown. Here we show that a specific S. aureus lineage evolved from a clone that expresses the accessory gene regulator (Agr) system to subclones that reversibly suppressed Agr and caused an outbreak in the hospital setting. S. aureus with flexible Agr regulation shows increased ability to acquire antibiotic-resistant plasmids, escape host immunity, and colonize mice. Bacteria with flexible Agr regulation shows altered cytosine genomic methylation, including the decreased 5mC methylation in transcriptional regulator genes (pcrA and rpsD), compared to strains with normal Agr expression patterns. In this work, we discover how altered genomic methylation promotes flexible Agr regulation which is associated with persistent pathogen colonization in the hospital environment., (© 2024. The Author(s).)

Lung injury activates epithelial stem or progenitor cells for alveolar repair and regeneration. Unraveling the origin and fate of injury-induced progenitors is crucial for elucidating lung repair mechanisms. Here, we report that p63-expressing progenitors emerge upon bleomycin-induced mouse lung injury. Single-cell RNA sequencing and clonal analysis reveal that these p63 + progenitors proliferate rapidly and differentiate into alveolar type 1 and type 2 cells through different trajectories. Dual recombinase-mediated sequential genetic-lineage tracing demonstrates that p63 + progenitors originate from airway secretory cells and subsequently generate alveolar cells. Functionally, p63 activation is essential for efficient alveolar regeneration from secretory cells post injury. Our study identifies secretory-cell-derived p63 + progenitors as contributors to alveolar repair, suggesting a potential therapeutic avenue for lung regeneration following injury., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

PDX1 is a crucial transcription factor in pancreas development and mature β-cell function. However, the regulation of PDX1 expression in larger animals mirroring human pancreas morphogenesis and endocrine maturation remains poorly understood. Therefore, we conducted a comparative analysis to characterize regulatory regions of goat PDX1 gene and assessed their transcriptional activity by transient transfection of several transgenic EGFP constructs in β- and non-β cell lines. We recognized several highly conserved regions encompassing the promoter and cis-regulatory elements (Area I-IV) at 5' flanking sequence of the genes. Within the promoter, we identified that a key E-box and nearby CAAT element synergistically drive transcription, constituting the basal promoter of goat PDX1 gene. Furthermore, each recognized regulatory area separately enhances this basal promoter activity in β-cells compared to non-β cells; however, cooperatively, they exhibit a bifunctional regulatory effect on transcription. Additionally, the intact ~ 3 kb upstream region (Area I-III) functions as the most efficient reporter transgene in vitro and shows islet-specific expression in native rat pancreas. Together, our findings suggest that the regulation of goat PDX1 gene is governed by conserved regions similar to other mammals, while both structurally and functionally, these regions exhibit a closer resemblance to those found in humans., (© 2024. The Author(s).)

Skeletal myofibers are syncytia made from the fusion of dozens or hundreds of mononuclear progenitor cells. Along myogenesis, the arriving nuclei from the progenitor cells have a long journey before being positioned at the periphery of a mature myofiber. Once at the periphery, nuclei are regularly spaced and each nucleus is transcriptionally responsible for its surrounding proportion of cytoplasm, known as the myonuclear domain. Disruption of these domains can be observed in various myopathies, suggesting their importance for skeletal muscle functionality. However, little is known about mechanisms regulating the myonuclear domain stability and organization. Here we take the example of MACF1, a microtubule-associated protein, as an essential actor in myonuclear domain organization, to highlight the potential role of microtubules and their associated proteome network for the stability of these domains and hence for proper myofiber functionality., (© 2024 médecine/sciences – Inserm.)

Gene expression emerges from DNA sequences through the interaction of transcription factors (TFs) with DNA cis-regulatory sequences. In eukaryotes, TFs bind to transcription factor binding sites (TFBSs) with differential affinities, enabling cell-specific gene expression. In this view, DNA enables TF binding along a continuum ranging from low to high affinity depending on its sequence composition; however, it is not known whether evolution has entailed a further level of entanglement between DNA-protein interaction. Here we found that the composition and length (22 bp) of the DNA sequence interposed between the CRX and NRL retinal TFs in the proximal promoter of RHODOPSIN (RHO) largely controls the expression levels of RHO. Mutagenesis of CRX-NRL DNA linking sequences (here termed "DNA-linker") results in uncorrelated gene expression variation. In contrast, mutual exchange of naturally occurring divergent human and mouse Rho cis-regulatory elements conferred similar yet species-specific Rho expression levels. Two orthogonal DNA-binding proteins targeted to the DNA-linker either activate or repress the expression of Rho depending on the DNA-linker orientation relative to the CRX and NRL binding sites. These results argue that, in this instance, DNA itself contributes to CRX and NRL activities through a code based on specific base sequences of a defined length, ultimately determining optimal RHO expression levels., (© 2024. The Author(s).)

The precise spatiotemporal expression of the hematopoietic ETS transcription factor PU.1, a key determinant of hematopoietic cell fates, is tightly regulated at the chromatin level. However, how chromatin signatures are linked to this dynamic expression pattern across different blood cell lineages remains uncharacterized. Here, we performed an in-depth analysis of the relationships between gene expression, chromatin structure, 3D architecture, and trans-acting factors at PU.1 cis-regulatory elements (PCREs). By identifying phylogenetically conserved DNA elements within chromatin-accessible regions in primary human blood lineages, we discovered multiple novel candidate PCREs within the upstream region of the human PU.1 locus. A subset of these elements localizes within an 8-kb-wide cluster exhibiting enhancer features, including open chromatin, demethylated DNA, enriched enhancer histone marks, present enhancer RNAs, and PU.1 occupation, presumably mediating PU.1 autoregulation. Importantly, we revealed the presence of a common 35-kb-wide CTCF-flanked insulated neighborhood that contains the PCRE cluster (PCREC), forming a chromatin territory for lineage-specific and PCRE-mediated chromatin interactions. These include functional PCRE-promoter interactions in myeloid and B cells that are absent in erythroid and T cells. By correlating chromatin structure and 3D architecture with PU.1 expression in various lineages, we were able to attribute enhancer versus silencer functions to individual elements. Our findings provide mechanistic insights into the interplay between dynamic chromatin structure and 3D architecture in the chromatin regulation of PU.1 expression. This study lays crucial groundwork for additional experimental studies that validate and dissect the role of PCREs in epigenetic regulation of normal and malignant hematopoiesis., (© 2024. The Author(s).)

As reported, long non-coding RNAs (lncRNAs) have been confirmed to be of great importance in regulating the progression of diseases, especially of cancers. LncRNA MACC1 antisense RNA 1 (MACC1-AS1) has been studied in some cancers, whereas its biological role and underlying mechanism is still unclear in small cell lung cancer (SCLC). In the current research, we found high level of MACC1-AS1 in SCLC cells. Subsequently, it was discovered that MACC1-AS1 knockdown considerably restrained the proliferative and migratory ability of SCLC cells by inducing the apoptosis. Importantly, the knockdown of MACC1-AS1 inhibited protein levels of genes of NOTCH pathway, and NOTCH pathway activator (Jagged1) countervailed the inhibition of MACC1-AS1 depletion on SCLC cell growth. Further, the deficiency of NOTCH1 hampered SCLC cell growth. More importantly, miR-579-3p was identified as a downstream gene of MACC1-AS1 and thereby targeted to NOTCH1. In addition, miR-579-3p repression recovered the suppressive role of MACC1-AS1 knockdown in NOTCH1 expression. Rescue assays indicated that repressed SCLC cell growth caused by MACC1-AS1 knockdown could be reserved by miR-579-3p repression or NOTCH1 overexpression. In brief, lncRNA MACC1-AS1 boosted SCLC cell growth via sequestering miR-579-3p and mediating NOTCH1-pathway., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), has a significantly higher risk of recurrence. However, the exact mechanism by which HBV prompts HCC recurrence remains largely unknown. In this study liver microarray test revealed significant upregulation of microtubule associated protein 1S (MAP1S) in metastatic HCC compared to control. MAP1S knockdown suppressed growth of HCCLM3 cells in vitro and in vivo. Mechanistically, HBV-encoded X protein (HBx) upregulates MAP1S, which enhances microtubule (MT) acetylation by promoting the degradation of histone deacetylase 6 (HDAC6), and facilitates the nuclear translocation of Smad complex, and thereby enhancing downstream TGF-β signaling. Smad complex, in turn, increases MAP1S, establishing a feedback loop of MAP1S/Smad/TGF-β1. Finally, survival analysis of 150 HBV-associated HCC patients demonstrated both increased MAP1S and decreased HDAC6 were significantly associated with shorter relapse-free survival. Collectively, this study reveals a unique mechanism whereby HBx-induced upregulation of MAP1S drives HBV-related HCC proliferation and migration through the MAP1S/Smad/TGF-β1 feedback loop. TEASER: MAP1S is a key link between HBV infection and a higher risk of metastatic recurrence of HCC., Competing Interests: Declaration of competing interest All authors declare no conflicting financial interests., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Activation-induced cytidine deaminase (AID, encoded by Aicda) plays a key role in somatic hypermutation and class switch recombination in germinal center B cells. However, off-target effects of AID are implicated in human leukemia and lymphoma. A mouse model of precursor B cell acute lymphoblastic leukemia driven by deletion of the related transcription factors PU.1 and Spi-B revealed C->T transition mutations compatible with being induced by AID. Therefore, we hypothesized that PU.1 negatively regulates Aicda during B cell development. Aicda mRNA transcript levels were increased in leukemia cells and bone marrow pre-B cells lacking PU.1 and/or Spi-B, relative to wild type cells. Using chromatin immunoprecipitation, PU.1 was found to interact with a negative regulatory region (R2-1) within the first intron of Aicda. CRISPR-Cas9-induced mutagenesis of R2-1 in cultured pre-B cells resulted in upregulation of Aicda in response to lipopolysaccharide stimulation. Mutation of the PU.1 interaction site and neighboring sequences resulted in reduced repressive ability of R2-1 in transient transfection analysis followed by luciferase assays. These results show that a PU.1-interacting intronic region negatively regulates Aicda transcription in developing B cells., Competing Interests: Declaration of Competing Interest The authors declare no competing interests, (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Aims: Cardiac fibrosis is characterized by aberrant collagen deposition in the heart. Macrophage polarization or infiltration is the main reason to accelerate the collagen deposition. We attempted to investigate the involvement of MKL1 in macrophages during the development of cardiac fibrosis., Materials and Methods: Cardiac fibrosis is induced by myocardial infarction (MI). The MKL1 f/f mice were crossed to the Lyz2-cre mice to generate macrophage conditional MKL1 knockout mice (MKL1 ΔMφ ). In addition, macrophage conditional MKL1 overexpression mice (MKL1 Mϕ-OE ) were constructed by crossing Lyz2-cre mice to MKL1 ΔN200-Rosa26 mice., Key Findings: MKL1 expression was significantly increased in macrophages of both ischemic cardiomyopathy (ICM) patients and mice induced to develop myocardial infarction. Deletion of MKL1 in macrophages improved the heart function after MI-induced cardiac fibrosis. Consistently, MKL1 Mϕ-OE mice displayed more severe cardiac fibrosis and worsened heart function than the control mice after MI. Moreover, administration of a small-molecule MKL1 inhibitor CCG-1423 also decreased the collagen deposition after MI., Significance: Our data demonstrate that MKL1 in macrophages contributes to cardiac fibrosis pathogenesis and reinforce the notion that targeting MKL1 may yield effective antifibrotic therapeutics in the heart., 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 © 2024. Published by Elsevier Inc.)

Introduction and Objectives: Blood glucose fluctuates severely in the diabetes (DM) and tumor microenvironment. Our previous works have found Hepatitis B virus X protein (HBx) differentially regulated metastasis and apoptosis of hepatoma cells depending on glucose concentration. We here aimed to explore whether HBx played dual roles in the angiogenesis of hepatocellular carcinoma varying on different glucose levels., Materials and Methods: We collected conditioned medium from HBx-overexpressing cells cultured with two solubilities of glucose, and then applied to EA.hy926 cells. Alternatively, a co-culture cell system was established with hepatoma cells and EA.hy926 cells. We analyzed the angiogenesis of EA.hy926 cells with CCK8, wound-healing, transwell-migartion and tube formation experiment. ELISA was conducted to detect the secretion levels of angiogenesis-related factors. siRNAs were used to detect the P53-VEGF axis., Results: HBx expressed in hepatoma cells suppressed VEGF secretion, and subsequently inhibited the proliferation, migration and tube formation of EA.hy926 cells in a high glucose condition, while attenuating these in the lower glucose condition. Furthermore, the p53-VEGF axis was required for the dual role of HBx in angiogenesis. Additionally, HBx mainly regulated the nuclear p53., Conclusions: These data suggest that the dual roles of HBx confer hepatoma cells to remain in a glucose-rich environment and escape from the glucose-low milieu through tumor vessels, promoting liver tumor progression overall. We exclusively revealed the dual role of HBx on the angiogenesis of liver tumors, which may shed new light on the mechanism and management strategy of HBV- and DM-related hepatocellular carcinoma., Competing Interests: Conflicts of interest None, (Copyright © 2024 Fundación Clínica Médica Sur, A.C. Published by Elsevier España, S.L.U. All rights reserved.)

This study aims to investigate the drug resistance, regulation mechanism of quorum sensing system, expression of related virulence genes, and epidemiological characteristics of carbapenem-resistant Pseudomonas aeruginosa (CRPA).In this study, Polymerase chain reaction amplification was performed to evaluate carbapenemase genes, OprD2 gene, quorum sensing system, and related virulence genes. Bacterial genotypes were analyzed using multilocus sequence typing and evolutionary analysis was conducted based on the goeBURST algorithm. The results demonstrated that a total of 47 CRPA strains were collected in this study, primarily from respiratory specimens in the ICU. Drug sensitivity results showed that the resistance rates of the 47 CRPA strains were highest for imipenem (97.87 %). The loss of OprD2 may be the main factor contributing to carbapenem resistance in our hospital's CRPA strains.All isolates tested positive for the quorum sensing system genes lasI and rhlI/R, and the virulence gene lasB was detected in all isolates, while the algD gene was detected in 19.15 % of the isolates. Among the 47 strains, 6 were untypeable, and the 41 strains with 28 different sequence types were clustered into three clonal complexes (BG1, BG2, and BG3).In conclusion, the CRPA isolates from our hospital exhibit high genetic diversity, with the deletion of the OprD2 gene possibly being the primary determinant of carbapenem resistance in Pseudomonas aeruginosa.Moreover, Las and RhI systems play a key role in quorum sensing signal system. Further research and development of drugs targeting quorum sensing signaling system may provide valuable guidance for the treatment of CRPA., 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 © 2024 Elsevier Ltd. All rights reserved.)

Germ cells mutant for bam or bgcn are locked in a germline stem cell (GSC)-like state, leading to tumor-like overgrowth in Drosophila ovaries. Our previous studies have demonstrated that germline overgrowth in bam mutants can be suppressed by defects in the miRNA pathway but enhanced by a null mutation in hippo. However, the genetic epistasis between the miRNA and Hippo pathways still remains unknown. Here, we determined that the miRNA pathway acts downstream of the Hippo pathway in regulating this process. Germ cells mutant for bam or bgcn and defective in both pathways divide very slowly, phenocopying those defective only in the miRNA pathway. In addition, we found that Yki, a key oncoprotein in the Hippo pathway, promotes the growth of both wild-type germ cells and bam mutant GSC-like cells. Like wild-type GSCs, bam mutant GSC-like cells predominantly stay in the G2 phase. Remarkably, many of those defective in the miRNA pathway are arrested before entering this phase. Furthermore, our studies identified bantam as a critical miRNA promoting germline overgrowth in bam or bgcn mutants. Taken together, these findings establish a genetic circuitry controlling Drosophila female germline overgrowth., (Copyright © 2024 Elsevier Inc. All rights reserved.)

We investigate the role and mechanism of imbalance via Th9 cells and Th17/Treg cells in the inflammatory and fibrotic phases of pulmonary fibrosis in mice. A total of mice were split into normal saline (control group) and inflammation and fibrosis mouse models (study group) randomly, and lung tissues and bronchoalveolar lavage fluid (BALF) were obtained from mice at the inflammatory and fibrotic phases on the 7th and 28th day, respectively. The degenerative changes in the mouse lung tissue were then visible using H&E staining. The expression of CCR6 and IL-9 in the lung tissues of two groups was examined through an immunohistochemistry assay. Fluorescence PCR was used to assess the expression of PU.1 mRNA in BALF, and flow cytometry was performed to identify the expression of Th17 and Treg. (1). The level of pulmonary fibrosis and lung inflammation in the research group was significantly higher than in the control group. (2). The expression of Th17, CCR6, IL-9 and PU.1 mRNA was substantially higher (P<0.05) in the research group at different time points; the expression level of Treg cells was considerably lower (P<0.05) in the research group than in the control group. (3). CCR6, IL-9 and PU.1 mRNA levels were statistically directly associated (P<0.05) with Th17 and inversely correlated 40 with Regulatory T cells (Tregs). CCR6 and Th9 cells may be involved in 45 developing Th17/Treg imbalance in the immune inflammation of pulmonary fibrosis, which promotes fibrocyte proliferation in lung tissue.

Background: As a component of the nucleosome remodeling and deacetylating (NuRD) complex, metastasis-associated protein 1 (MTA1) has been reported to be abundant in male reproductive system and might participate in spermatogenesis and sperm maturation, whereas the precise functional role of MTA1 in these processes is still undetermined., Objective: To investigate the effect and potential function of MTA1 in male fertility., Materials and Methods: Mta1 knockout mice (Mta1 -/- ) were employed to detect their reproductive phenotype. The pH value of Mta1 -/- epididymal luminal fluid was measured, and the potential mechanism of MTA1 involved in regulating luminal acidification was detected in vivo and in vitro. A vasectomy model with abnormal pH of epididymal lumen was established to further detect the effect of MTA1 on epididymal luminal microenvironment., Results: Mta1 -/- mice were fertile without any detectable defects in spermatogenesis or sperm motility while the deficiency of MTA1 could acidify the initial segment of epididymis to a certain extent. MTA1 could interact with estrogen receptor alpha (ERα) and inhibit the transcription of ERα target gene, hydrogen exchanger 3 (NHE3), and ultimately affect the epididymal luminal milieu. After vasectomy, the Mta1 -/- mice presented a more acidic epididymal lumen which was closer to the normal state compared to the wild-type model., Discussion and Conclusion: MTA1 is dispensable for male fertility in mice, but plays a potentially important function in regulating luminal acidification of the epididymis., (© 2024 American Society of Andrology and European Academy of Andrology.)

The transcription factor (TF) cone-rod homeobox (CRX) is essential for the differentiation and maintenance of photoreceptor cell identity. Several human CRX variants cause degenerative retinopathies, but most are variants of uncertain significance. We performed a deep mutational scan (DMS) of nearly all possible single amino acid substitutions in CRX using a cell-based transcriptional reporter assay, curating a high-confidence list of nearly 2000 variants with altered transcriptional activity. In the structured homeodomain, activity scores closely aligned to a predicted structure and demonstrated position-specific constraints on amino acid substitution. In contrast, the intrinsically disordered transcriptional effector domain displayed a qualitatively different pattern of substitution effects, following compositional constraints without specific residue position requirements in the peptide chain. These compositional constraints were consistent with the acidic exposure model of transcriptional activation. We evaluated the performance of the DMS assay as a clinical variant classification tool using gold-standard classified human variants from ClinVar, identifying pathogenic variants with high specificity and moderate sensitivity. That this performance could be achieved using a synthetic reporter assay in a foreign cell type, even for a highly cell type-specific TF like CRX, suggests that this approach shows promise for DMS of other TFs that function in cell types that are not easily accessible. Together, the results of the CRX DMS identify molecular features of the CRX effector domain and demonstrate utility for integration into the clinical variant classification pipeline., (© 2024 Shepherdson et al.; Published by Cold Spring Harbor Laboratory Press.)

Background: Hepatitis B virus (HBV) infection is a persistent global public health problem, and curing for chronic hepatitis B (CHB) through the application of existing antiviral drugs is beset by numerous challenges. The viral protein HBx is a critical regulatory factor in the life cycle of HBV. Targeting HBx is a promising possibility for the development of novel therapeutic strategies., Methods: The Nano-Glo ® HiBiT Lysis Detection System was used to screen the herbal monomer compound library for compounds that inhibit HBx expression. Western blotting was used to examine proteins expression. Southern blotting or Northern blotting were used to detect HBV DNA or HBV RNA. ELISA was performed to detect the HBsAg level. The effect of asiatic acid on HBV in vivo was investigated by using recombinant cccDNA mouse model., Results: Asiatic acid, an extract of Centella asiatica, significantly reduced the HBx level. Mechanistic studies demonstrated that asiatic acid may promote the degradation of HBx in an autophagy pathway-dependent manner. Subsequently, asiatic acid was found to reduce the amount of HBx bound to covalently closed circular DNA (cccDNA) microchromosomes, and repressive chromatin modifications then occurred, ultimately inhibiting cccDNA transcriptional activity. Moreover, in HBV-infected cells and a mouse model of persistent HBV infection, asiatic acid exhibited potent anti-HBV activity, as evidenced by decreased levels of HBV RNAs, HBV DNA and HBsAg., Conclusions: Asiatic acid was identified as a compound that targets HBx, revealing its potential for application as an anti-HBV agent., (© 2024. The Author(s).)

RNA binding proteins drive proliferation and tumorigenesis by regulating the translation and stability of specific subsets of messenger RNAs (mRNAs). We have investigated the role of eukaryotic initiation factor 4B (eIF4B) in this process and identify 10-fold more RNA binding sites for eIF4B in tumour cells from patients with diffuse large B-cell lymphoma compared to control B cells and, using individual-nucleotide resolution UV cross-linking and immunoprecipitation, find that eIF4B binds the entire length of mRNA transcripts. eIF4B stimulates the helicase activity of eIF4A, thereby promoting the unwinding of RNA structure within the 5' untranslated regions of mRNAs. We have found that, in addition to its well-documented role in mRNA translation, eIF4B additionally interacts with proteins associated with RNA turnover, including UPF1 (up-frameshift protein 1), which plays a key role in histone mRNA degradation at the end of S phase. Consistent with these data, we locate an eIF4B binding site upstream of the stem-loop structure in histone mRNAs and show that decreased eIF4B expression alters histone mRNA turnover and delays cell cycle progression through S phase. Collectively, these data provide insight into how eIF4B promotes tumorigenesis., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Pseudomonas plecoglossicida is a causative agent of visceral granulomas in large yellow croaker ( Larimichthys crocea ). Quorum sensing (QS) is widely involved in imparting virulence to pathogenic bacteria; however, it has not been studied in P. plecoglossicida . In this study, we annotated a LuxR family transcriptional regulator in P. plecoglossicida NB2011 and designated as PplR. We aligned the protein sequence by BlastP and Clustal X2, monitored the N-acyl-homoserine lactone (AHL) signal production through cross-feeding bioassay and HC-MS/MS; investigated exogenous AHL signal binding by recombinant expression and thin layer chromatography; constructed a deletion mutant of the target gene by method of double homologous recombination; sequenced the transcript RNA and analyzed the data; additionally, characterized phenotypes of wild type and mutant strain. The LuxR homolog PplR was found to share high similarity with PpoR-the LuxR solo of Pseudomonas putida -without a cognate LuxI. The wild-type strain did not produce any AHL signals and the recombinant LuxR protein was found to bind C6-L-homoserine lactone (C6-HSL), C8-HSL, 3-oxo-C10-HSL, and 3-oxo-C12-HSL. RNA-seq analysis indicated 84 differentially expressed genes-5 upregulated and 79 downregulated-mainly enriched in gene ontology terms, such as flagella-dependent motility, integral component of membrane, DNA binding and transcription, and metal ion binding, suggesting that PplR is a master transcription regulator. The mutant strain showed attenuated biofilm-forming ability and stress resistance, and the data support a role for PplR in the regulation of these traits in P. plecoglossicida NB2011 independent of the presence of AHL signals. This is the first study to provide QS-related information on P. plecoglossicida ., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Jia, Chi, Chen and Mao.)

Background: Calmodulin-binding transcription activator (CAMTA) is comprised of a group of transcription factors and plays an important role in the Ca 2+ signaling pathway, mediating various molecular responses via interactions with other transcription factors and binding to the promoter region of specific genes. Mung beans (Vigna radiata) are one of the most commonly consumed commodities in Asia. To date, CAMTA proteins have not been characterized in this important crop plant., Results: Eight paralogous VrCAMTA genes were identified and found to be distributed on five of the 11 chromosomes. The proteins possessed CG-1 DNA-binding domains with bipartite NLS signals, ankyrin domains, CaM-binding IQ motifs, and CaM-binding domain (CaMBD). The 2 kb upstream regions of VrCAMTA genes contained sequence motifs of abscisic acid-responsive elements (ABRE) and ethylene-responsive elements (ERE), and binding sites for transcription factors of the bZIP and bHLH domains. Analysis of RNA-seq data from a public repository revealed ubiquitous expression of the VrCAMTA genes, as VrCAMTA1 was expressed at the highest level in seedling leaves, whereas VrCAMTA8 was expressed at the lowest level, which agreed with the RT-qPCR analysis performed on the first true leaves. On day four after leaf emergence, all VrCAMTA genes were upregulated, with VrCAMTA1 exhibiting the highest degree of upregulation. In darkness on day 4, upregulation was not observed in most VrCAMTA genes, except VrCAMTA7, for which a low degree of upregulation was found, whereas no difference was found in VrCAMTA8 expression between light and dark conditions. Treatment with calcium ionophores enhanced VrCAMTA expression under light and/or dark conditions at different times after leaf emergence, suggesting that calcium signaling is involved in the light-induced upregulation of VrCAMTA gene expression., Conclusions: The expression dependence of nearly all VrCAMTA genes on light and calcium signaling suggests their possible differential but likely complementary roles during the early stages of mung bean growth and development., (© 2024. The Author(s).)

Bioluminescence in Vibrio fischeri is regulated by a quorum-dependent signaling system composed of LuxI and LuxR. LuxI generates N- 3-oxohexanoyl homoserine lactone (3OC6-HSL), which triggers LuxR to activate transcription of the luxICDABEG operon responsible for bioluminescence. Surprisingly, a ∆ luxI mutant produced more bioluminescence than the wild type in culture. In contrast, a 4 bp duplication within luxI , resulting in a frameshift mutation and null allele, decreased luminescence tenfold. A second signaling system encoded by ainSR affects bioluminescence by increasing levels of LuxR, via the transcriptional activator LitR, and the N- octanoyl homoserine lactone (C8-HSL) signal produced by AinS is considered only a weak activator of LuxR. However, ainS is required for the bright phenotype of the ∆ luxI mutant in culture. When 3OC6-HSL was provided either in the medium or by expression of luxI in trans , all cultures were brighter, but the ∆ luxI mutant remained significantly brighter than the luxI frameshift mutant. Taken together, these data suggest that the enhanced bioluminescence due to the LuxI product 3OC6-HSL counteracts a negative cis -acting regulatory element within the luxI gene and that when luxI is absent the C8-HSL signal is sufficient to induce luminescence., Importance: The regulation of bioluminescence by Vibrio fischeri is a textbook example of bacterial quorum-dependent pheromone signaling. The canonical regulatory model is that an autoinducer pheromone produced by LuxI accumulates as cells achieve a high density, and this LuxI-generated signal stimulates LuxR to activate transcription of the lux operon that underlies bioluminescence. The surprising observation that LuxI is dispensable for inducing bioluminescence forces a re-evaluation of the role of luxI . More broadly, the results underscore the potential deceptiveness of complex regulatory circuits, particularly those in which bacteria produce multiple related signaling molecules., Competing Interests: The authors declare no conflict of interest.

In 2011, in Germany, Escherichia coli O104:H4 caused the enterohemorrhagic E coli (EHEC) outbreak with the highest incidence rate of hemolytic uremic syndrome. This pathogen carries an exceptionally potent combination of EHEC- and enteroaggregative E coli (EAEC)-specific virulence factors. Here, we identified an E coli O104:H4 isolate that carried a single-nucleotide polymorphism (SNP) in the start codon (ATG > ATA) of rpoS, encoding the alternative sigma factor S. The rpoS ATG > ATA SNP was associated with enhanced EAEC-specific virulence gene expression. Deletion of rpoS in E coli O104:H4 Δstx2 and typical EAEC resulted in a similar effect. Both rpoS ATG > ATA and ΔrpoS strains exhibited stronger virulence-related phenotypes in comparison to wild type. Using promoter-reporter gene fusions, we demonstrated that wild-type RpoS repressed aggR, encoding the main regulator of EAEC virulence. In summary, our work demonstrates that RpoS acts as a global repressor of E coli O104:H4 virulence, primarily through an AggR-dependent mechanism., Competing Interests: Potential conflicts of interest. The authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Abdominal aortic aneurysm (AAA) is a life-threatening cardiovascular disease that has been linked to gut microbiome dysbiosis. Therefore, this study aims to investigate the effects of Akkermansia muciniphila ( Am ) on AAA mice and the biomolecules involved. AAA mice were generated using angiotensin II (Ang II), and 16sRNA sequencing was used to identify an altered abundance of microbiota in the feces of AAA mice. Vascular smooth muscle cell (VSMC) markers and apoptosis, and macrophage infiltration in mouse aortic tissues were examined. The abundance of Am was reduced in AAA mouse feces, and endothelial PAS domain-containing protein 1 (EPAS1) was downregulated in AAA mice and VSMC induced with Ang II. Am delayed AAA progression in mice, which was blunted by knockdown of EPAS1. EPAS1 was bound to the Cbp/p300-interacting transactivator 2 (CITED2) promoter and promoted CITED2 transcription. CITED2 reduced VSMC apoptosis and delayed AAA progression. Moreover, EPAS1 inhibited macrophage inflammatory response by promoting CITED2 transcription. In conclusion, gut microbiome dysbiosis in AAA induces EPAS1-mediated dysregulation of CITED2 to promote macrophage inflammatory response and VSMC apoptosis., Competing Interests: The authors declare no conflict of interest.

Background: Staphylococcus aureus is the predominant pathogen isolated in diabetic foot infections. Recently, the skin commensal bacterium, Helcococcus kunzii, was found to modulate the virulence of this pathogen in an in vivo model. This study aims to elucidate the molecular mechanisms underlying the interaction between these two bacterial species, using a proteomic approach., Results: Our results reveal that H. kunzii can coexist and proliferate alongside S. aureus in a Chronic Wound Media (CWM), thereby mimicking an in vitro chronic wound environment. We noted that the secreted proteome of H. kunzii induced a transcriptional effect on S. aureus virulence, resulting in a decrease in the expression level of agrA, a gene involved in quorum sensing. The observed effect could be ascribed to specific proteins secreted by H. kunzii including polysaccharide deacetylase, peptidoglycan DD-metalloendopeptidase, glyceraldehyde-3-phosphate dehydrogenase, trypsin-like peptidase, and an extracellular solute-binding protein. These proteins potentially interact with the agr system, influencing S. aureus virulence. Additionally, the virulence of S. aureus was notably affected by modifications in iron-related pathways and components of cell wall architecture in the presence of H. kunzii. Furthermore, the overall metabolism of S. aureus was reduced when cocultured with H. kunzii., Conclusion: Future research will focus on elucidating the role of these excreted factors in modulating virulence., (© 2024. The Author(s).)

While cell fate determination and maintenance are important in establishing and preserving tissue identity and function during development, aberrant cell fate transition leads to cancer cell heterogeneity and resistance to treatment. Here, we report an unexpected role for the transcription factor p63 (Trp63/TP63) in the fate choice of the squamous versus neuroendocrine lineage in esophageal development and malignancy. Deletion of p63 results in extensive neuroendocrine differentiation in the developing mouse esophagus and esophageal progenitors derived from human embryonic stem cells. In human esophageal neuroendocrine carcinoma (eNEC) cells, p63 is transcriptionally silenced by EZH2-mediated H3K27 trimethylation (H3K27me3). Up-regulation of the major p63 isoform ΔNp63α, through either ectopic expression or EZH2 inhibition, promotes squamous transdifferentiation of eNEC cells. Together, these findings uncover p63 as a rheostat in coordinating the transition between squamous and neuroendocrine cell fates during esophageal development and tumor progression.

Two retinal transcription factors, cone-rod homeobox (CRX) and neural retina leucine zipper (NRL), cooperate functionally and physically to control photoreceptor development and homeostasis. Mutations in CRX and NRL cause severe retinal diseases. Despite the roles of NRL and CRX, insight into their functions at the molecular level is lacking. Here, we have solved the crystal structure of the CRX homeodomain in complex with its cognate response element (Ret4) from the rhodopsin proximal promoter region. The structure reveals an unexpected 2:1 stoichiometry of CRX/Ret4 and unique orientation of CRX molecules on DNA, and it explains the mechanisms of pathogenic mutations in CRX. Mutations R41Q and E42K disrupt the CRX protein-protein contacts based on the structure and reduce the CRX/Ret4 binding stoichiometry, suggesting a novel disease mechanism. Furthermore, we show that NRL alters the stoichiometry and increases affinity of CRX binding at the rhodopsin promoter, which may enhance transcription of rod-specific genes and suppress transcription of cone-specific genes., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Hutchinson-Gilford progeria syndrome (HGPS) is an extremely rare disease caused by the expression of progerin, an aberrant protein produced by a point mutation in the LMNA gene. HGPS patients show accelerated aging and die prematurely mainly from complications of atherosclerosis such as myocardial infarction, heart failure, or stroke. However, the mechanisms underlying HGPS vascular pathology remain ill-defined. We used single-cell RNA sequencing to characterize the aorta in progerin-expressing LmnaG609G/G609G mice and wild-type controls, with a special focus on endothelial cells (ECs). HGPS ECs showed gene expression changes associated with extracellular matrix alterations, increased leukocyte extravasation, and activation of the yes-associated protein 1/transcriptional activator with PDZ-binding domain (YAP/TAZ) mechanosensing pathway, all validated by different techniques. Atomic force microscopy experiments demonstrated stiffer subendothelial extracellular matrix in progeroid aortae, and ultrasound assessment of live HGPS mice revealed disturbed aortic blood flow, both key inducers of the YAP/TAZ pathway in ECs. YAP/TAZ inhibition with verteporfin reduced leukocyte accumulation in the aortic intimal layer and decreased atherosclerosis burden in progeroid mice. Our findings identify endothelial YAP/TAZ signaling as a key mechanism of HGPS vascular disease and open a new avenue for the development of YAP/TAZ-targeting drugs to ameliorate progerin-induced atherosclerosis.

Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) play fundamental roles in stem/progenitor cell expansion during homeostasis, and their dysregulation often leads to tissue overgrowth. Here, we show that YAP activation is sufficient to overcome the restriction of global protein synthesis induced by serum starvation, enabling cells to sustain proliferation and survival despite an unfavorable environment. Mechanistically, YAP/TAZ selectively promoted the mTORC1-dependent translation of mRNAs containing 5' terminal oligopyrimidine (5'TOP) motifs, ultimately increasing the cellular polysome content. Interestingly, DNA damage-inducible transcript 4 (DDIT4), a negative regulator of mTORC1, was upregulated by serum starvation but repressed by YAP/TAZ. DDIT4 was sufficient to suppress the translation and transformative potential of uveal melanoma cells, which are often serum unresponsive due to G protein mutations. Our findings reveal a vital role for protein synthesis as a key modality of YAP/TAZ-induced oncogenic transformation and indicate the potential for targeting mTORC1 or translation to treat YAP/TAZ-driven malignancies., (© 2024. The Author(s).)

Epithelioid hemangioendothelioma (EHE) is a rare malignant vascular tumor arising from vascular endothelial cells. This study delves into the molecular mechanisms underlying EHE, with a specific focus on the Hippo-YAP/TAZ pathway. EHE is characterized molecularly by transcriptional co-activator with a PDZ-motif (TAZ)-calmodulin binding transcription activator 1 (CAMTA1) or Yes-associated protein (YAP)-transcription factor E3 (TFE3) fusions. YAP/TAZ, a transcription co-activator, binds to transcription factors and regulates gene expression. The YAP/TAZ and its upstream Hippo pathway are involved in cell proliferation and cell contact inhibition, regulating organ size and carcinogenesis. In addition to oncogenic effects, dysfunction or gene duplication of the Hippo pathway results in a poor prognosis due to epithelial-mesenchymal transformation of epithelial cells, stem cell transformation, and increased drug resistance. Notably, the TAZ-CAMTA1 fusion is specific to EHE, and genetic alterations in the Hippo pathway other than this fusion gene are absent in EHE. The TAZ-CAMTA1 fusion is a promising therapeutic target. This review summarizes recent advances in EHE, focusing on the role of the Hippo-YAP/TAZ pathway in EHE and its potential as a therapeutic target for drug development., (Copyright © 2024 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Fold-switching enables metamorphic proteins to reversibly interconvert between two highly dissimilar native states to regulate their protein functions. While about 100 proteins have been identified to undergo fold-switching, unveiling the key residues behind this mechanism for each protein remains challenging. Reasoning that fold-switching in proteins is driven by dynamic changes in local energetic frustration, we combined fold-switching simulations generated using simplified structure-based models with frustration analysis to identify key residues involved in this process based on the change in the density of minimally frustrated contacts during refolding. Using this approach to analyze the fold-switch of the bacterial transcription factor RfaH, we identified 20 residues that significantly change their frustration during its fold-switch, some of which have been experimentally and computationally reported in previous works. Our approach, which we developed as an additional module for the FrustratometeR package, highlights the role of local frustration dynamics in protein fold-switching and offers a robust tool to enhance our understanding of other proteins with significant conformational shifts., (© 2024 The Protein Society.)

Transcription factor (TF) DNA-binding dynamics govern cell fate and identity. However, our ability to pharmacologically control TF localization is limited. Here we leverage chemically driven binding site restriction leading to robust and DNA-sequence-specific redistribution of PU.1, a pioneer TF pertinent to many hematopoietic malignancies. Through an innovative technique, 'CLICK-on-CUT&Tag', we characterize the hierarchy of de novo PU.1 motifs, predicting occupancy in the PU.1 cistrome under binding site restriction. Temporal and single-molecule studies of binding site restriction uncover the pioneering dynamics of native PU.1 and identify the paradoxical activation of an alternate target gene set driven by PU.1 localization to second-tier binding sites. These transcriptional changes were corroborated by genetic blockade and site-specific reporter assays. Binding site restriction and subsequent PU.1 network rewiring causes primary human leukemia cells to differentiate. In summary, pharmacologically induced TF redistribution can be harnessed to govern TF localization, actuate alternate gene networks and direct cell fate., (© 2024. The Author(s).)

The Allis group identified Gcn5 as the first transcription-related lysine acetyltransferase in 1996, providing a molecular "missing link" between chromatin organization and gene regulation. This review will focus on functions subsequently identified for Gcn5 and the closely related PCAF protein, in the context of two major complexes, SAGA and ATAC, and how the study of these enzymes informs long standing questions regarding the importance of lysine acetylation., Competing Interests: Conflict of interest The author declares that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Yes-associated protein (YAP) and its homolog, transcriptional coactivator with PDZ-binding motif (TAZ), are the main transcriptional downstream effectors of the Hippo pathway. Decreased Hippo pathway activity leads to nuclear translocation of YAP/TAZ where they interact with TEAD transcription factors to induce target gene expression. Unrestrained YAP/TAZ activity can lead to excessive growth and tumor formation in a short time, underscoring the evolutionary need for tight control of these two transcriptional coactivators. Here, we report that the AP-1 component JUN acts as specific repressor of YAP/TAZ at joint target sites to decrease YAP/TAZ activity. This function of JUN is independent of its heterodimeric AP-1 partner FOS and the canonical AP-1 function. Since expression of JUN is itself induced by YAP/TAZ, our work identifies a JUN-dependent negative feedback loop that buffers YAP/TAZ activity at joint genomic sites. This negative feedback loop gets disrupted in liver cancer to unlock the full oncogenic potential of YAP/TAZ. Our results thus demonstrate an additional layer of control for the interplay of YAP/TAZ and AP-1., (© 2024. The Author(s).)

Background: Triple-negative breast cancer (TNBC) is a subtype of breast cancer that lacks the expression of three receptors commonly targeted in breast cancer treatment. In this study, the research focused on investigating the role of centrosomal protein 55 (CEP55) in TNBC progression and its interaction with the transcription factor Spi-1 proto-oncogene (SPI1)., Methods: Various techniques including qRT-PCR, western blotting, and immunohistochemistry assays were utilized to examine gene expression patterns. Functional assays such as wound-healing assay, transwell invasion assay, 5-Ethynyl-2'-deoxyuridine assay, and metabolic assays were conducted to assess the impact of CEP55 on the behaviors of TNBC cells. CD163-positive macrophages were quantified by flow cytometry. The chromatin immunoprecipitation assay and dual-luciferase reporter assay were performed to assess the association of SPI1 with CEP55. A xenograft mouse model experiment was used to analyze the impact of SPI1 on tumor development in vivo., Results: CEP55 and SPI1 expression levels were significantly upregulated in TNBC tissues and cells. The depletion of CEP55 led to decreased TNBC cell migration, invasion, proliferation, glucose metabolism, and M2 macrophage polarization, indicating its crucial role in promoting TNBC progression. Moreover, SPI1 transcriptionally activated CEP55 in TNBC cells, and its overexpression was associated with accelerated tumor growth in vivo. Further, CEP55 overexpression relieved SPI1 silencing-induced inhibitory effects on TNBC cell migration, invasion, proliferation, glucose metabolism, and M2 macrophage polarization., Conclusion: SPI1-mediated transcriptional activation of CEP55 plays a key role in enhancing TNBC cell migration, invasion, proliferation, glucose metabolism, and M2 macrophage polarization. These insights provide valuable information for potential targeted therapies to combat TNBC progression by modulating the SPI1-CEP55 axis., 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 © 2024 Elsevier GmbH. All rights reserved.)

Dysregulated actin cytoskeleton gives rise to aberrant cell motility and metastatic spread of tumor cells. This study evaluates the effect of overexpression of wild-type versus functional mutants of MRTF-A on migration and invasion of breast cancer (BC) cells. Our studies indicate that SRF's interaction is critical for MRTF-A-induced promotion of both two-dimensional and three-dimensional cell migration, while the SAP-domain function is important selectively for three-dimensional cell migration. Increased MRTF-A activity is associated with more effective membrane protrusion, a phenotype that is attributed predominantly to SRF's interaction with MRTF. We demonstrate formin-family protein mDia2 as an important mediator of MRTF-stimulated actin polymerization at the leading edge and cell migration. Multiplexed quantitative immunohistochemistry and transcriptome analyses of clinical BC specimens further demonstrate a positive correlation between nuclear localization of MRTF with malignant traits of cancer cells and enrichment of MRTF-SRF gene signature in pair-matched distant metastases versus primary tumors. In conclusion, this study establishes a novel mechanism of MRTF-dependent regulation of cell migration and provides evidence for the association between MRTF activity and increased malignancy in human BC, justifying future development of specific small molecule inhibitors of the MRTF-SRF transcriptional complex as potential therapeutic agents in BC., Competing Interests: Conflicts of interest: The authors declare no competing conflict of interest.

Aim: To assess the expression and function of miR-483-5p in diabetic β cells., Methods: The expression of miR-483-5p was evaluated in the pancreatic islets of obesity mouse models by quantitative reverse transcription polymerase chain reaction. Dual-luciferase activity, and western blotting assays, were utilized for miR-483-5p target gene verification. Mice with β cell-specific miR-483-5p downregulation were studied under metabolic stress (i.e. a high-fat diet) condition. Lineage tracing was used to determine β-cell fate., Results: miR-483-5p increased in the islets of obese mouse models. Expression levels of miR-483-5p were significantly upregulated with the treatment of high glucose and palmitate, in both MIN6 cells and mouse islets. Overexpression of miR-483-5p in β cells results in impaired insulin secretion and β-cell identity. Cell lineage-specific analyses revealed that miR-483-5p overexpression deactivated β-cell identity genes (insulin, Pdx1 and MafA) and derepressed β-cell dedifferentiation (Ngn3) genes. miR-483-5p downregulation in β cells of high-fat diet-fed mice alleviated diabetes and improved glucose intolerance by enhancing insulin secretory capacity. These detrimental effects of miR-483-5p relied on its seed sequence recognition and repressed expression of its target genes Pdx1 and MafA, two crucial markers of β-cell maturation., Conclusions: These findings indicate that the miR-483-5p-mediated reduction of mRNAs specifies β-cell identity as a contributor to β-cell dysfunction via the loss of cellular differentiation., (© 2024 John Wiley & Sons Ltd.)

The activation of yes-associated protein 1 (YAP1) and transcriptional co-activator with PDZ-binding motif (TAZ) has been implicated in both regeneration and tumorigenesis, thus representing a double-edged sword in tissue homeostasis. However, how the activity of YAP1/TAZ is regulated or what leads to its dysregulation in these processes remains unknown. To explore the upstream stimuli modulating the cellular activity of YAP1/TAZ, we developed a highly sensitive YAP1/TAZ/TEAD-responsive DNA element (YRE) and incorporated it into a lentivirus-based reporter cell system to allow for sensitive and specific monitoring of the endogenous activity of YAP1/TAZ in terms of luciferase activity in vitro and Venus fluorescence in vivo. Furthermore, by replacing YRE with TCF- and NF-κB-binding DNA elements, we demonstrated the applicability of this reporter system to other pathways such as Wnt/β-catenin/TCF- and IL-1β/NF-κB-mediated signaling, respectively. The practicality of this system was evaluated by performing cell-based reporter screening of a chemical compound library consisting of 364 known inhibitors, using reporter-introduced cells capable of quantifying YAP1/TAZ- and β-catenin-mediated transcription activities, which led to the identification of multiple inhibitors, including previously known as well as novel modulators of these signaling pathways. We further confirmed that novel YAP1/TAZ modulators, such as potassium ionophores, Janus kinase inhibitors, platelet-derived growth factor receptor inhibitors, and genotoxic stress inducers, alter the protein level or phosphorylation of endogenous YAP1/TAZ and the expression of their target genes. Thus, this reporter system provides a powerful tool to monitor endogenous signaling activities of interest (even in living cells) and search for modulators in various cellular contexts., (© 2024 The Author(s). Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Yorkie (Yki) is a key effector of the Hippo pathway that activates the expression of targets by associating with the transcription factor Scalloped. Various upstream signals, such as cell polarity and mechanical cues, control transcriptional programs by regulating Yki activity. Searching for Yki regulatory factors has far-reaching significance for studying the Hippo pathway in development and human diseases. In this study, we identify Calpain-A (CalpA) and Calpain-B (CalpB), two calcium (Ca 2+ )-dependent modulatory proteases of the calpain family, as critical regulators of Yki in Drosophila that interact with Yki, respectively. Ca 2+ induces Yki cleavage in a CalpA/CalpB-dependent manner, and the protease activity of CalpA/CalpB is pivotal for the cleavage. Furthermore, overexpression of CalpA or CalpB in Drosophila partially restores the large wing phenotype caused by Yki overexpression, and F98 of Yki is an important cleavage site by the Ca 2+ -calpains axis. Our study uncovers a unique mechanism whereby the Ca 2+ -calpain axis modulates Yki activity through protein cleavage., Competing Interests: Conflict of interest The authors declare no competing interests., (Copyright © 2024 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.)

Artesunate (ART) is a derivative of artemisinin and has anti-inflammatory, anti-tumor, and anti-angiogenic properties. Although ART has been implicated in osteoarthritis (OA), the mechanism needs to be further dissected. Here, we explored the effects of ART on the development of OA and the underlying mechanism using destabilization of the medial meniscus (DMM) surgical instability model. Mice with OA were developed using DMM and treated with ART. The pathological morphology of knee joint tissues was examined, and the degeneration of joint cartilage was assessed. Mouse knee chondrocytes were isolated and induced with IL-1β, followed by ART treatment. ART alleviates OA in mice by elevating ubiquitin carboxyl-terminal hydrolase 7 (USP7) expression, and USP7 inhibitor (P22077) treatment mitigated the protective effects of ART on chondrocytes. We also showed that USP7 mediated the deubiquitination of forkhead box protein O1 (FoxO1), while FoxO1 alleviated chondrocyte injury. In addition, FoxO1 promoted metastasis-associated protein MTA1 (MTA1) transcription, and downregulation of MTA1 exacerbated chondrocyte injury. Our study identifies that USP7/FoxO1/MTA1 is a key signaling cascade in the treatment of ART on OA., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to declare., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: Chronic hepatitis B virus (HBV) infection is the primary risk factor for the malignant progression of hepatocellular carcinoma (HCC). It has been reported that HBV X protein (HBx) possesses oncogenic properties, promoting hepatocarcinogenesis and chemoresistance. However, the detailed molecular mechanisms are not fully understood. Here, we aim to investigate the effects of miR-128-3p/SPG21 axis on HBx-induced hepatocarcinogenesis and chemoresistance., Methods: The expression of SPG21 in HCC was determined using bioinformatics analysis, quantitative real-time PCR (qRT-PCR), western blotting, and immunohistochemistry (IHC). The roles of SPG21 in HCC were elucidated through a series of in vitro and in vivo experiments, including real-time cellular analysis (RTCA), matrigel invasion assay, and xenograft mouse model. Pharmacologic treatment and flow cytometry were performed to demonstrate the potential mechanism of SPG21 in HCC., Results: SPG21 expression was elevated in HCC tissues compared to adjacent non-tumor tissues (NTs). Moreover, higher SPG21 expression correlated with poor overall survival. Functional assays revealed that SPG21 fostered HCC tumorigenesis and invasion. MiR-128-3p, which targeted SPG21, was downregulated in HCC tissues. Subsequent analyses showed that HBx amplified TRPM7-mediated calcium influx via miR-128-3p/SPG21, thereby activating the c-Jun N-terminal kinase (JNK) pathway. Furthermore, HBx inhibited doxorubicin-induced apoptosis by engaging the JNK pathway through miR-128-3p/SPG21., Conclusion: The study suggested that SPG21, targeted by miR-128-3p, might be involved in enhancing HBx-induced carcinogenesis and doxorubicin resistance in HCC via the TRPM7/Ca 2+ /JNK signaling pathway. This insight suggested that SPG21 could be recognized as a potential oncogene, offering a novel perspective on its role as a prognostic factor and a therapeutic target in the context of HCC., (© 2024. Springer Nature Switzerland AG.)

Background: Phyllodes tumors (PTs) of the breast are uncommon fibroepithelial neoplasms that tend to recur locally and may have metastatic potential. Their pathogenesis is poorly understood. Hippo signaling pathway plays an essential role in organ size control, tumor suppression, tissue regeneration and stem cell self-renewal. Hippo signaling dysfunction has been implicated in cancer. Recent evidence suggests that there is cross-talk between the Hippo signaling key proteins YAP/TAZ and the epithelial-mesenchymal transition (EMT) master regulators Snail and ZEB. In this study we aimed to investigate the expression of Hippo signaling pathway components and EMT regulators in PTs, in relation to tumor grade., Methods: Expression of Hippo signaling effector proteins YAP, TAZ and their DNA binding partner TEAD was evaluated by immunohistochemistry in paraffin-embedded tissue specimens from 86 human phyllodes breast tumors (45 benign, 21 borderline, 20 malignant), in comparison with tumor grade and with the expression of EMT-related transcription factors ZEB and Snail., Results: Nuclear immunopositivity for YAP, TAZ and TEAD was detected in both stromal and epithelial cells in PTs and was significantly higher in high grade tumors. Interestingly, there was a significant correlation between the expression of YAP, TAZ, TEAD and the expression of ZEB and SNAIL., Conclusions: Our results originally implicate Hippo signaling pathway in PTs pathogenesis and suggest that an interaction between Hippo signaling key components and EMT regulators may promote the malignant features of PTs., Competing Interests: Declaration of Competing Interest We have no conflicts of interest to disclose. The authors received no specific funding for this work., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Metastatic cutaneous melanoma is a fatal skin cancer. Resistance to targeted and immune therapies limits the benefits of current treatments. Identifying and adding anti-resistance agents to current treatment protocols can potentially improve clinical responses. Myocardin-related transcription factor (MRTF) is a transcriptional coactivator whose activity is indirectly regulated by actin and the Rho family of GTPases. We previously demonstrated that development of BRAF inhibitor (BRAFi) resistance frequently activates the Rho/MRTF pathway in human and mouse BRAF V600E melanomas. In clinical trials, pretreatment with BRAFi reduces the benefit of immune therapies. We aimed to test the efficacy of concurrent treatment with our MRTF pathway inhibitor CCG-257081 and anti-PD1 in vivo and to examine its effects on the melanoma immune microenvironment. Because MRTF pathway activation upregulates the expression of immune checkpoint inhibitor genes/proteins, we asked whether CCG-257081 can improve the response to immune checkpoint blockade. CCG-257081 reduced the expression of PDL1 in BRAFi-resistant melanoma cells and decreased surface PDL1 levels on both BRAFi-sensitive and -resistant melanoma cells. Using our recently described murine vemurafenib-resistant melanoma model, we found that CCG-257081, in combination with anti-PD1 immune therapy, reduced tumor growth and increased survival. Moreover, anti-PD1/CCG-257081 co-treatment increased infiltration of CD8 + T cells and B cells into the tumor microenvironment and reduced tumor-associated macrophages. Here, we propose CCG-257081 as an anti-resistance and immune therapy-enhancing anti-melanoma agent., (© 2024 The Author(s). International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.)