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1.
Pathol Res Pract ; 254: 155131, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38309018

RESUMO

Diabetes has been a significant healthcare problem worldwide for a considerable period. The primary objective of diabetic treatment plans is to control the symptoms associated with the pathology. To effectively combat diabetes, it is crucial to comprehend the disease's etiology, essential factors, and the relevant processes involving ß-cells. The development of the pancreas, maturation, and maintenance of ß-cells, and their role in regular insulin function are all regulated by PDX1. Therefore, understanding the regulation of PDX1 and its interactions with signaling pathways involved in ß-cell differentiation and proliferation are crucial elements of alternative diabetes treatment strategies. The present review aims to explore the protective role of PDX1 in ß-cell proliferation through signaling pathways. The main keywords chosen for this review include "PDX1 for ß-cell mass," "ß-cell proliferation," "ß-cell restoration via PDX1," and "mechanism of PDX1 in ß-cells." A comprehensive literature search was conducted using various internet search engines, such as PubMed, Science Direct, and other publication databases. We summarize several approaches to generating ß-cells from alternative cell sources, employing PDX1 under various modified growth conditions and different transcriptional factors. Our analysis highlights the unique potential of PDX1 as a promising target in molecular and cell-based therapies for diabetes.


Assuntos
Diabetes Mellitus , Proteínas de Homeodomínio , Células Secretoras de Insulina , Transativadores , Humanos , Diabetes Mellitus/terapia , Diabetes Mellitus/metabolismo , Proteínas de Homeodomínio/metabolismo , Células Secretoras de Insulina/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo
2.
Development ; 151(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38345326

RESUMO

Morphogen gradients provide essential positional information to gene networks through their spatially heterogeneous distribution, yet how they form is still hotly contested, with multiple models proposed for different systems. Here, we focus on the transcription factor Bicoid (Bcd), a morphogen that forms an exponential gradient across the anterior-posterior (AP) axis of the early Drosophila embryo. Using fluorescence correlation spectroscopy we find there are spatial differences in Bcd diffusivity along the AP axis, with Bcd diffusing more rapidly in the posterior. We establish that such spatially varying differences in Bcd dynamics are sufficient to explain how Bcd can have a steep exponential gradient in the anterior half of the embryo and yet still have an observable fraction of Bcd near the posterior pole. In the nucleus, we demonstrate that Bcd dynamics are impacted by binding to DNA. Addition of the Bcd homeodomain to eGFP::NLS qualitatively replicates the Bcd concentration profile, suggesting this domain regulates Bcd dynamics. Our results reveal how a long-range gradient can form while retaining a steep profile through much of its range.


Assuntos
Proteínas de Drosophila , Proteínas de Homeodomínio , Animais , Padronização Corporal/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Embrião não Mamífero/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Transativadores/genética , Transativadores/metabolismo
3.
Nat Commun ; 15(1): 1385, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360978

RESUMO

The Eyes Absent proteins (EYA1-4) are a biochemically unique group of tyrosine phosphatases known to be tumour-promoting across a range of cancer types. To date, the targets of EYA phosphatase activity remain largely uncharacterised. Here, we identify Polo-like kinase 1 (PLK1) as an interactor and phosphatase substrate of EYA4 and EYA1, with pY445 on PLK1 being the primary target site. Dephosphorylation of pY445 in the G2 phase of the cell cycle is required for centrosome maturation, PLK1 localization to centrosomes, and polo-box domain (PBD) dependent interactions between PLK1 and PLK1-activation complexes. Molecular dynamics simulations support the rationale that pY445 confers a structural impairment to PBD-substrate interactions that is relieved by EYA-mediated dephosphorylation. Depletion of EYA4 or EYA1, or chemical inhibition of EYA phosphatase activity, dramatically reduces PLK1 activation, causing mitotic defects and cell death. Overall, we have characterized a phosphotyrosine signalling network governing PLK1 and mitosis.


Assuntos
Proteínas de Ciclo Celular , Proteínas Serina-Treonina Quinases , Humanos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Ciclo Celular/metabolismo , Tirosina/metabolismo , Mitose , Centrossomo/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Células HeLa , Proteínas Nucleares/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Transativadores/metabolismo
4.
Cell Death Dis ; 15(2): 129, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38342917

RESUMO

Neural stem cells (NSCs) are critical for brain development and maintenance of neurogenesis. However, the molecular mechanisms that regulate NSC proliferation and differentiation remain unclear. Mysm1 is a deubiquitinase and is essential for the self-renewal and differentiation of several stem cells. It is unknown whether Mysm1 plays an important role in NSCs. Here, we found that Mysm1 was expressed in NSCs and its expression was increased with age in mice. Mice with Mysm1 knockdown by crossing Mysm1 floxed mice with Nestin-Cre mice exhibited abnormal brain development with microcephaly. Mysm1 deletion promoted NSC proliferation and apoptosis, resulting in depletion of the stem cell pool. In addition, Mysm1-deficient NSCs skewed toward neurogenesis instead of astrogliogenesis. Mechanistic investigations with RNA sequencing and genome-wide CUT&Tag analysis revealed that Mysm1 epigenetically regulated Id4 transcription by regulating histone modification at the promoter region. After rescuing the expression of Id4, the hyperproliferation and imbalance differentiation of Mysm1-deficient NSCs was reversed. Additionally, knockdown Mysm1 in aged mice could promote NSC proliferation. Collectively, the present study identified a new factor Mysm1 which is essential for NSC homeostasis and Mysm1-Id4 axis may be an ideal target for proper NSC proliferation and differentiation.


Assuntos
Células-Tronco Neurais , Proteases Específicas de Ubiquitina , Camundongos , Animais , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo , Endopeptidases/metabolismo , Transativadores/metabolismo , Diferenciação Celular/fisiologia , Células-Tronco Neurais/metabolismo , Proliferação de Células/genética
5.
Proc Natl Acad Sci U S A ; 121(6): e2310821121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38300873

RESUMO

Impaired expression of MHC (major histocompatibility complex) class I in cancers constitutes a major mechanism of immune evasion. It has been well documented that the low level of MHC class I is associated with poor prognosis and resistance to checkpoint blockade therapies. However, there is lmited approaches to specifically induce MHC class I to date. Here, we show an approach for robust and specific induction of MHC class I by targeting an MHC class I transactivator (CITA)/NLRC5, using a CRISPR/Cas9-based gene-specific system, designated TRED-I (Targeted reactivation and demethylation for MHC-I). The TRED-I system specifically recruits a demethylating enzyme and transcriptional activators on the NLRC5 promoter, driving increased MHC class I antigen presentation and accelerated CD8+ T cell activation. Introduction of the TRED-I system in an animal cancer model exhibited tumor-suppressive effects accompanied with increased infiltration and activation of CD8+ T cells. Moreover, this approach boosted the efficacy of checkpoint blockade therapy using anti-PD1 (programmed cell death protein) antibody. Therefore, targeting NLRC5 by this strategy provides an attractive therapeutic approach for cancer.


Assuntos
Genes MHC Classe I , Neoplasias , Animais , Genes MHC Classe I/genética , Antígenos de Histocompatibilidade Classe I , Transativadores/metabolismo , Neoplasias/genética , Desmetilação
6.
Int J Mol Sci ; 25(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338812

RESUMO

Biosensors based on allosteric transcription factors have been widely used in synthetic biology. In this study, we utilized the Acinetobacter ADP1 transcription factor PobR to develop a biosensor activating the PpobA promoter when bound to its natural ligand, 4-hydroxybenzoic acid (4HB). To screen for PobR mutants responsive to 4-hydroxyphenylpyruvate(HPP), we developed a dual selection system in E. coli. The positive selection of this system was used to enrich PobR mutants that identified the required ligands. The following negative selection eliminated or weakened PobR mutants that still responded to 4HB. Directed evolution of the PobR library resulted in a variant where PobRW177R was 5.1 times more reactive to 4-hydroxyphenylpyruvate than PobRWT. Overall, we developed an efficient dual selection system for directed evolution of biosensors.


Assuntos
Técnicas Biossensoriais , Ácidos Fenilpirúvicos , Transativadores , Transativadores/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Fatores de Transcrição/metabolismo
7.
J Virol ; 98(2): e0177623, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38197630

RESUMO

Epstein-Barr virus (EBV) has a lifelong latency period after initial infection. Rarely, however, when the EBV immediate early gene BZLF1 is expressed by a specific stimulus, the virus switches to the lytic cycle to produce progeny viruses. We found that EBV infection reduced levels of various ceramide species in gastric cancer cells. As ceramide is a bioactive lipid implicated in the infection of various viruses, we assessed the effect of ceramide on the EBV lytic cycle. Treatment with C6-ceramide (C6-Cer) induced an increase in the endogenous ceramide pool and increased production of the viral product as well as BZLF1 expression. Treatment with the ceramidase inhibitor ceranib-2 induced EBV lytic replication with an increase in the endogenous ceramide pool. The glucosylceramide synthase inhibitor Genz-123346 inhibited C6-Cer-induced lytic replication. C6-Cer induced extracellular signal-regulated kinase 1/2 (ERK1/2) and CREB phosphorylation, c-JUN expression, and accumulation of the autophagosome marker LC3B. Treatment with MEK1/2 inhibitor U0126, siERK1&2, or siCREB suppressed C6-Cer-induced EBV lytic replication and autophagy initiation. In contrast, siJUN transfection had no impact on BZLF1 expression. The use of 3-methyladenine (3-MA), an inhibitor targeting class III phosphoinositide 3-kinases (PI3Ks) to inhibit autophagy initiation, resulted in reduced beclin-1 expression, along with suppressed C6-Cer-induced BZLF1 expression and LC3B accumulation. Chloroquine, an inhibitor of autophagosome-lysosome fusion, increased BZLF1 protein intensity and LC3B accumulation. However, siLC3B transfection had minimal effect on BZLF1 expression. The results suggest the significance of ceramide-related sphingolipid metabolism in controlling EBV latency, highlighting the potential use of drugs targeting sphingolipid metabolism for treating EBV-positive gastric cancer.IMPORTANCEEpstein-Barr virus remains dormant in the host cell but occasionally switches to the lytic cycle when stimulated. However, the exact molecular mechanism of this lytic induction is not well understood. In this study, we demonstrate that Epstein-Barr virus infection leads to a reduction in ceramide levels. Additionally, the restoration of ceramide levels triggers lytic replication of Epstein-Barr virus with increase in phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and CREB. Our study suggests that the Epstein-Barr virus can inhibit lytic replication and remain latent through reduction of host cell ceramide levels. This study reports the regulation of lytic replication by ceramide in Epstein-Barr virus-positive gastric cancer.


Assuntos
Carcinoma , Infecções por Vírus Epstein-Barr , Neoplasias Gástricas , Humanos , Herpesvirus Humano 4/genética , Proteína Quinase 3 Ativada por Mitógeno , Ativação Viral , Transativadores/metabolismo , Ceramidas/farmacologia , Interações Hospedeiro-Patógeno/genética
8.
Appl Environ Microbiol ; 90(2): e0137423, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38251894

RESUMO

The acyl-homoserine lactones (AHLs)-mediated LuxI/LuxR quorum sensing (QS) system orchestrates diverse bacterial behaviors in response to changes in population density. The role of the BjaI/BjaR1 QS system in Bradyrhizobium diazoefficiens USDA 110, which shares homology with LuxI/LuxR, remains elusive during symbiotic interaction with soybean. Here this genetic system in wild-type (WT) bacteria residing inside nodules exhibited significantly reduced activity compared to free-living cells, potentially attributed to soybean-mediated suppression. The deletion mutant strain ΔbjaR1 showed significantly enhanced nodulation induction and nitrogen fixation ability. Nevertheless, its ultimate symbiotic outcome (plant dry weight) in soybeans was compromised. Furthermore, comparative analysis of the transcriptome, proteome, and promoter activity revealed that the inactivation of BjaR1 systematically activated and inhibited genomic modules associated with nodulation and nitrogen metabolism. The former appeared to be linked to a significant decrease in the expression of NodD2, a key cell-density-dependent repressor of nodulation genes, while the latter conferred bacterial growth and nitrogen fixation insensitivity to environmental nitrogen. In addition, BjaR1 exerted a positive influence on the transcription of multiple genes involved in a so-called central intermediate metabolism within the nodule. In conclusion, our findings highlight the crucial role of the BjaI/BjaR1 QS circuit in positively regulating bacterial nitrogen metabolism and emphasize the significance of the soybean-mediated suppression of this genetic system for promoting efficient symbiotic nitrogen fixation by B. diazoefficiens.IMPORTANCEThe present study demonstrates, for the first time, that the BjaI/BjaR1 QS system of Bradyrhizobium diazoefficiens has a significant impact on its nodulation and nitrogen fixation capability in soybean by positively regulating NodD2 expression and bacterial nitrogen metabolism. Moreover, it provides novel insights into the importance of suppressing the activity of this QS circuit by the soybean host plant in establishing an efficient mutual relationship between the two symbiotic partners. This research expands our understanding of legumes' role in modulating symbiotic nitrogen fixation through rhizobial QS-mediated metabolic functioning, thereby deepening our comprehension of symbiotic coevolution theory. In addition, these findings may hold great promise for developing quorum quenching technology in agriculture.


Assuntos
Bradyrhizobium , Percepção de Quorum/fisiologia , Fixação de Nitrogênio , Simbiose/fisiologia , Bradyrhizobium/genética , Bradyrhizobium/metabolismo , Transativadores/metabolismo , Nitrogênio/metabolismo
9.
mBio ; 15(2): e0127823, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38259061

RESUMO

Cross-feeding of metabolites between subpopulations can affect cell phenotypes and population-level behaviors. In chronic Pseudomonas aeruginosa lung infections, subpopulations with loss-of-function (LOF) mutations in the lasR gene are common. LasR, a transcription factor often described for its role in virulence factor expression, also impacts metabolism, which, in turn, affects interactions between LasR+ and LasR- genotypes. Prior transcriptomic analyses suggested that citrate, a metabolite secreted by many cell types, induces virulence factor production when both genotypes are together. An unbiased analysis of the intracellular metabolome revealed broad differences including higher levels of citrate in lasR LOF mutants. Citrate consumption by LasR- strains required the CbrAB two-component system, which relieves carbon catabolite repression and is elevated in lasR LOF mutants. Within mixed communities, the citrate-responsive two-component system TctED and its gene targets OpdH (porin) and TctABC (citrate transporter) that are predicted to be under catabolite repression control were induced and required for enhanced RhlR/I-dependent signaling, pyocyanin production, and fitness of LasR- strains. Citrate uptake by LasR- strains markedly increased pyocyanin production in co-culture with Staphylococcus aureus, which also secretes citrate and frequently co-infects with P. aeruginosa. This citrate-induced restoration of virulence factor production by LasR- strains in communities with diverse species or genotypes may offer an explanation for the contrast observed between the markedly deficient virulence factor production of LasR- strains in monocultures and their association with the most severe forms of cystic fibrosis lung infections. These studies highlight the impact of secreted metabolites in mixed microbial communities.IMPORTANCECross-feeding of metabolites can change community composition, structure, and function. Here, we unravel a cross-feeding mechanism between frequently co-observed isolate genotypes in chronic Pseudomonas aeruginosa lung infections. We illustrate an example of how clonally derived diversity in a microbial communication system enables intra- and inter-species cross-feeding. Citrate, a metabolite released by many cells including P. aeruginosa and Staphylococcus aureus, was differentially consumed between genotypes. Since these two pathogens frequently co-occur in the most severe cystic fibrosis lung infections, the cross-feeding-induced virulence factor expression and fitness described here between diverse genotypes exemplify how co-occurrence can facilitate the development of worse disease outcomes.


Assuntos
Fibrose Cística , Infecções por Pseudomonas , Humanos , Pseudomonas aeruginosa/metabolismo , Transativadores/genética , Transativadores/metabolismo , Percepção de Quorum/genética , Fibrose Cística/complicações , Piocianina , Ácido Cítrico/metabolismo , Fatores de Virulência/metabolismo , Citratos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo
10.
ACS Synth Biol ; 13(2): 568-589, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38206199

RESUMO

Programmable intercellular signaling using components of naturally occurring quorum sensing can allow for coordinated functions to be engineered in microbial consortia. LuxR-type transcriptional regulators are widely used for this purpose and are activated by homoserine lactone (HSL) signals. However, they often suffer from imperfect molecular discrimination of structurally similar HSLs, causing misregulation within engineered consortia containing multiple HSL signals. Here, we studied one such example, the regulator LasR from Pseudomonas aeruginosa. We elucidated its sequence-function relationship for ligand specificity using targeted protein engineering and multiplexed high-throughput biosensor screening. A pooled combinatorial saturation mutagenesis library (9,486 LasR DNA sequences) was created by mutating six residues in LasR's ß5 sheet with single, double, or triple amino acid substitutions. Sort-seq assays were performed in parallel using cognate and noncognate HSLs to quantify each corresponding sensor's response to each HSL signal, which identified hundreds of highly specific variants. Sensor variants identified were individually assayed and exhibited up to 60.6-fold (p = 0.0013) improved relative activation by the cognate signal compared to the wildtype. Interestingly, we uncovered prevalent mutational epistasis and previously unidentified residues contributing to signal specificity. The resulting sensors with negligible signal crosstalk could be broadly applied to engineer bacteria consortia.


Assuntos
Proteínas de Bactérias , Transativadores , Transativadores/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Transdução de Sinais , Pseudomonas aeruginosa/metabolismo , Mutação , Percepção de Quorum/genética , 4-Butirolactona/metabolismo , Regulação Bacteriana da Expressão Gênica
11.
Hereditas ; 161(1): 1, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167241

RESUMO

INTRODUCTION: The bicoid (bcd) gene in Drosophila has served as a paradigm for a morphogen in textbooks for decades. Discovered in 1986 as a mutation affecting anterior development in the embryo, its expression pattern as a protein gradient later confirmed the prediction from transplantation experiments. These experiments suggested that the protein fulfills the criteria of a true morphogen, with the existence of a homeodomain crucial for activation of genes along the anterior-posterior axis, based on the concentration of the morphogen. The bcd gene undergoes alternative splicing, resulting in, among other isoforms, a small and often neglected isoform with low abundance, which lacks the homeodomain, termed small bicoid (smbcd). Most importantly, all known classical strong bcd alleles used in the past to determine bcd function apparently do not affect the function of this isoform. RESULTS: To overcome the uncertainty regarding which isoform regulates what, I removed the bcd locus entirely using CRISPR technology. bcdCRISPR eggs exhibited a short and round appearance. The phenotype could be ascribed to smbcd because all bcd alleles affecting the function of the major transcript, termed large bicoid (lgbcd) showed normally sized eggs. Several patterning genes for the embryo showed expression in the oocyte, and their expression patterns were altered in bcdCRISPR oocytes. In bcdCRISPR embryos, all downstream segmentation genes showed altered expression patterns, consistent with the expression patterns in "classical" alleles; however, due to the altered egg geometry resulting in fewer blastoderm nuclei, additional constraints came into play, further affecting their expression patterns. CONCLUSIONS: This study unveils a novel and fundamental role of bcd in shaping the egg's geometry. This discovery demands a comprehensive revision of our understanding of this important patterning gene and prompts a reevaluation of past experiments conducted under the assumption that bcd mutants were bcdnull-mutants.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Transativadores/genética , Transativadores/metabolismo , Isoformas de Proteínas/metabolismo , Padronização Corporal/genética
12.
Sci Rep ; 14(1): 156, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38167847

RESUMO

Salmonella enterica serovar Typhimurium causes gastroenteritis and systemic infections in humans. For this bacterium the expression of a type III secretion system (T3SS) and effector proteins encoded in the Salmonella pathogenicity island-1 (SPI-1), is keystone for the virulence of this bacterium. Expression of these is controlled by a regulatory cascade starting with the transcriptional regulators HilD, HilC and RtsA that induce the expression of HilA, which then activates expression of the regulator InvF, a transcriptional regulator of the AraC/XylS family. InvF needs to interact with the chaperone SicA to activate transcription of SPI-1 genes including sicA, sopB, sptP, sopE, sopE2, and STM1239. InvF very likely acts as a classical activator; however, whether InvF interacts with the RNA polymerase alpha subunit RpoA has not been determined. Results from this study confirm the interaction between InvF with SicA and reveal that both proteins interact with the RNAP alpha subunit. Thus, our study further supports that the InvF/SicA complex acts as a classical activator. Additionally, we showed for the first time an interaction between a chaperone of T3SS effectors (SicA) and the RNAP.


Assuntos
Proteínas de Ligação a DNA , Salmonella typhimurium , Humanos , Salmonella typhimurium/metabolismo , Proteínas de Ligação a DNA/genética , Transativadores/genética , Transativadores/metabolismo , Proteínas de Bactérias/metabolismo , Fatores de Transcrição/metabolismo , Chaperonas Moleculares/metabolismo , Regulação Bacteriana da Expressão Gênica
13.
Cell Mol Life Sci ; 81(1): 65, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38281222

RESUMO

Loss of GLI-Similar 3 (GLIS3) function in mice and humans causes congenital hypothyroidism (CH). In this study, we demonstrate that GLIS3 protein is first detectable at E15.5 of murine thyroid development, a time at which GLIS3 target genes, such as Slc5a5 (Nis), become expressed. This, together with observations showing that ubiquitous Glis3KO mice do not display major changes in prenatal thyroid gland morphology, indicated that CH in Glis3KO mice is due to dyshormonogenesis rather than thyroid dysgenesis. Analysis of GLIS3 in postnatal thyroid suggested a link between GLIS3 protein expression and blood TSH levels. This was supported by data showing that treatment with TSH, cAMP, or adenylyl cyclase activators or expression of constitutively active PKA enhanced GLIS3 protein stability and transcriptional activity, indicating that GLIS3 activity is regulated at least in part by TSH/TSHR-mediated activation of PKA. The TSH-dependent increase in GLIS3 transcriptional activity would be critical for the induction of GLIS3 target gene expression, including several thyroid hormone (TH) biosynthetic genes, in thyroid follicular cells of mice fed a low iodine diet (LID) when blood TSH levels are highly elevated. Like TH biosynthetic genes, the expression of cell cycle genes is suppressed in ubiquitous Glis3KO mice fed a LID; however, in thyroid-specific Glis3 knockout mice, the expression of cell cycle genes was not repressed, in contrast to TH biosynthetic genes. This indicated that the inhibition of cell cycle genes in ubiquitous Glis3KO mice is dependent on changes in gene expression in GLIS3 target tissues other than the thyroid.


Assuntos
Glândula Tireoide , Fatores de Transcrição , Humanos , Camundongos , Animais , Glândula Tireoide/metabolismo , Fatores de Transcrição/metabolismo , Hormônios Tireóideos/metabolismo , Tireotropina/genética , Tireotropina/metabolismo , Tireotropina/farmacologia , Regulação da Expressão Gênica , Proteínas de Ligação a DNA/genética , Proteínas Repressoras/genética , Transativadores/metabolismo
14.
Hematol Oncol ; 42(1): e3251, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38287528

RESUMO

Zinc finger protein 384 (ZNF384) rearrangement defined a novel subtype of B-cell acute lymphoblastic leukemia (B-ALL). The prognostic significance of ZNF384 fusion transcript levels represented measurable residual disease remains to be explored. ZNF384 fusions were screened out in 57 adult B-ALL patients at diagnosis by real-time quantitative polymerase chain reaction and their transcript levels were serially monitored during treatment. The reduction of ZNF384 fusion transcript levels at the time of achieving complete remission had no significant impact on survival, whereas its ≥2.5-log reduction were significantly associated with higher relapse free survival (RFS) and overall survival (OS) rates after course 1 consolidation (p = 0.022 and = 0.0083) and course 2 consolidation (p = 0.0025 and = 0.0008). Compared with chemotherapy alone, allogeneic hematopoietic stem cell transplantation (allo-HSCT) significantly improved RFS and OS of patients with <2.5-log reduction after course 1 consolidation (p < 0.0001 and = 0.0002) and course 2 consolidation (p = 0.0003 and = 0.019), whereas exerted no significant effects in patients with ≥2.5-log reduction (all p > 0.05). ZNF384 fusion transcript levels after course 1 and course 2 consolidation strongly predict relapse and survival and may guide whether receiving allo-HSCT in adult B-ALL.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto , Humanos , Prognóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Fatores de Transcrição , Neoplasia Residual/diagnóstico , Recidiva , Transativadores/metabolismo , Transativadores/uso terapêutico
15.
Sci Rep ; 14(1): 2448, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291092

RESUMO

In China, there has been a persistent upward trend in the incidence and mortality rates of colorectal cancer (CRC), with CRC ranking second in incidence and fifth in mortality among all malignant tumors. Although circular RNAs (circRNAs) have been implicated in the progression of various cancers, their specific role in CRC progression remains largely unexplored. The objective of this study was to elucidate the role and underlying mechanisms of circXRN2 in CRC. Differential expression of circXRN2 was identified through whole transcriptome sequencing. The expression levels of circXRN2 and miR-149-5p were quantified in CRC tissues, corresponding adjacent normal tissues, and CRC cell lines using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The stability of circXRN2 was confirmed through RNase R and actinomycin D experiments. The binding interaction between circXRN2 and miR-149-5p was validated through RNA pull-down, RNA immunoprecipitation, and dual-luciferase assays. The biological functions of circXRN2 were assessed through a battery of in vitro experiments, including the CCK-8 assay, EdU assay, scratch assay, Transwell assay, and flow cytometry assay. Additionally, in vivo experiments involving a tumor transplantation model and a liver-lung metastasis model were conducted. The influence of circXRN2 on the expression of epithelial-mesenchymal transition (EMT)-related genes was determined via Western blotting analysis. In CRC tissues and cells, there was an upregulation in the expression levels of both circXRN2 and ENC1, while miR-149-5p exhibited a downregulation in its expression. The overexpression of circXRN2 was found to enhance tumor proliferation and metastasis, as evidenced by results from both in vitro and in vivo experiments. Functionally, circXRN2 exerted its antitumor effect by suppressing cell proliferation, migration, and invasion while also promoting apoptosis. Mechanistically, the dysregulated expression of circXRN2 had an impact on the expression of proteins within the EMT signaling pathway. Our results demonstrated that circXRN2 promoted the proliferation and metastasis of CRC cells through the miR-149-5p/ENC1/EMT axis, suggesting that circXRN2 might serve as a potential therapeutic target and novel biomarker in the progression of CRC.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Neoplasias Pulmonares , MicroRNAs , Humanos , MicroRNAs/metabolismo , Neoplasias Colorretais/patologia , Linhagem Celular , Neoplasias Pulmonares/genética , Neoplasias Hepáticas/genética , Transição Epitelial-Mesenquimal/genética , Proliferação de Células/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Transativadores/metabolismo
16.
EMBO Mol Med ; 16(1): 10-39, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38177530

RESUMO

Endocrine resistance is a crucial challenge in estrogen receptor alpha (ERα)-positive breast cancer (BCa). Aberrant alteration in modulation of E2/ERα signaling pathway has emerged as the putative contributor for endocrine resistance in BCa. Herein, we demonstrate that MYSM1 as a deubiquitinase participates in modulating ERα action via histone and non-histone deubiquitination. MYSM1 is involved in maintenance of ERα stability via ERα deubiquitination. MYSM1 regulates relevant histone modifications on cis regulatory elements of ERα-regulated genes, facilitating chromatin decondensation. MYSM1 is highly expressed in clinical BCa samples. MYSM1 depletion attenuates BCa-derived cell growth in xenograft models and increases the sensitivity of antiestrogen agents in BCa cells. A virtual screen shows that the small molecule Imatinib could potentially interact with catalytic MPN domain of MYSM1 to inhibit BCa cell growth via MYSM1-ERα axis. These findings clarify the molecular mechanism of MYSM1 as an epigenetic modifier in regulation of ERα action and provide a potential therapeutic target for endocrine resistance in BCa.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Receptor alfa de Estrogênio/genética , Moduladores de Receptor Estrogênico/farmacologia , Moduladores de Receptor Estrogênico/uso terapêutico , Histonas/metabolismo , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Transativadores/metabolismo , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo
17.
PLoS Comput Biol ; 20(1): e1011802, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38227575

RESUMO

The effects of transcription factor binding sites (TFBSs) on the activity of a cis-regulatory element (CRE) depend on the local sequence context. In rod photoreceptors, binding sites for the transcription factor (TF) Cone-rod homeobox (CRX) occur in both enhancers and silencers, but the sequence context that determines whether CRX binding sites contribute to activation or repression of transcription is not understood. To investigate the context-dependent activity of CRX sites, we fit neural network-based models to the activities of synthetic CREs composed of photoreceptor TFBSs. The models revealed that CRX binding sites consistently make positive, independent contributions to CRE activity, while negative homotypic interactions between sites cause CREs composed of multiple CRX sites to function as silencers. The effects of negative homotypic interactions can be overcome by the presence of other TFBSs that either interact cooperatively with CRX sites or make independent positive contributions to activity. The context-dependent activity of CRX sites is thus determined by the balance between positive heterotypic interactions, independent contributions of TFBSs, and negative homotypic interactions. Our findings explain observed patterns of activity among genomic CRX-bound enhancers and silencers, and suggest that enhancers may require diverse TFBSs to overcome negative homotypic interactions between TFBSs.


Assuntos
Transativadores , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Transativadores/metabolismo , Proteínas de Homeodomínio/genética , Regulação da Expressão Gênica , Sítios de Ligação/genética , Retina
18.
Mycoses ; 67(1): e13680, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38214420

RESUMO

CIITA, a member of NOD-like receptor (NLR) family, is the major MHC II trans-activator and mediator of Th1 immunity, but its function and interaction with NLRP3 have been little studied. We found activation of NLRP3 inflammasome, increased expression of CIITA, CBP, pSTAT1, STAT1, MHC II, IFN-γ and IFN-γ-inducible chemokines (CCL1 and CXCL8), and colocalisation of NLRP3 with CIITA in Malassezia folliculitis lesions, Malassezia globosa-infected HaCaT cells and mouse skin. CoIP with anti-CIITA or anti-NLRP3 antibody pulled down NLRP3 or both CIITA and ASC. NLRP3 silencing or knockout caused CIITA downexpression and their colocalisation disappearance in HaCaT cells and mouse skin of Nlrp3-/- mice, while CIITA knockdown had no effect on NLRP3, ASC, IL-1ß and IL-18 expression. NLRP3 inflammasome inhibitors and knockdown significantly suppressed IFN-γ, CCL1, CXCL8 and CXCL10 levels in M. globosa-infected HaCaT cells. CCL1 and CXCL8 expression was elevated in Malassezia folliculitis lesions and reduced in Nlrp3-/- mice. These results demonstrate that M. globosa can activate NLRP3 inflammasome, CIITA/MHC II signalling and IFN-γ-inducible chemokines in human keratinocytes and mouse skin. NLRP3 may regulate CIITA by their binding and trigger Th1 immunity by secreting CCL1 and CXCL8/IL-8, contributing to the pathogenesis of Malassezia-associated skin diseases.


Assuntos
Quimiocinas C , Foliculite , Malassezia , Humanos , Camundongos , Animais , Interferon gama , Interferons , Antígenos de Histocompatibilidade Classe II/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Inflamassomos , Regiões Promotoras Genéticas , Transativadores/genética , Transativadores/metabolismo , Quimiocinas/genética , Queratinócitos
19.
Epigenetics ; 19(1): 2293409, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38232183

RESUMO

Long noncoding RNAs (lncRNAs) regulate the progression of type 2 diabetes mellitus complicated with obstructive sleep apnoea (T2DM-OSA). However, the role of the lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) in T2DM-OSA remains unknown. This study aimed to reveal the function of NEAT1 in T2DM-OSA and the underlying mechanism. KKAy mice were exposed to intermittent hypoxia (IH) or intermittent normoxia to generate a T2DM-OSA mouse model. HMEC-1 cells were treated with high glucose (HG) and IH to construct a T2DM-OSA cell model. RNA expression was detected by qRT-PCR. The protein expression of Apelin, NF-E2-related factor 2 (Nrf2), haem oxygenase-1 (HO-1), and up-frameshift suppressor 1 (UPF1) was assessed using western blot. Cell injury was evaluated using flow cytometry, enzyme-linked immunosorbent assay, and oxidative stress kit assays. RIP, RNA pull-down, and actinomycin D assays were performed to determine the associations between NEAT1, UPF1, and Apelin. NEAT1 expression was upregulated in the aortic vascular tissues of mice with T2DM exposed to IH and HMEC-1 cells stimulated with HG and IH, whereas Apelin expression was downregulated. The absence of NEAT1 protected HMEC-1 cells from HG- and IH-induced damage. Furthermore, NEAT1 destabilized Apelin mRNA by recruiting UPF1. Apelin overexpression decreased HG- and IH-induced injury to HMEC-1 cells by activating the Nrf2/HO-1 pathway. Moreover, NEAT1 knockdown reduced HG- and IH-induced injury to HMEC-1 cells through Apelin. NEAT1 silencing reduced HMEC-1 cell injury through the Apelin/Nrf2/HO-1 signalling pathway in T2DM-OSA.Abbreviations: LncRNAs, long non-coding RNAs; T2DM, type 2 diabetes mellitus; OSA, obstructive sleep apnoea; NEAT1, nuclear paraspeckle assembly transcript 1; IH, intermittent hypoxia; HMEC-1, human microvascular endothelial cells; HG, high glucose; Nrf2, NF-E2-related factor 2; UPF1, up-frameshift suppressor 1; HO-1, haem oxygenase-1; qRT-PCR, quantitative real-time polymerase chain reaction; ELISA, enzyme-linked immunosorbent assay; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; TNF-α, tumour necrosis factor-α; CCK-8, Cell Counting Kit-8; IL-1ß, interleukin-1ß; ROS, reactive oxygen species; MDA, malondialdehyde; SOD, superoxide dismutase; RIP, RNA immunoprecipitation; SD, standard deviations; GSH, glutathione; AIS, acute ischaemic stroke; HMGB1, high mobility group box-1 protein; TLR4, toll-like receptor 4.


Assuntos
Isquemia Encefálica , Diabetes Mellitus Tipo 2 , RNA Helicases , RNA Longo não Codificante , Apneia Obstrutiva do Sono , Acidente Vascular Cerebral , Animais , Humanos , Camundongos , Apelina/genética , Apelina/metabolismo , Isquemia Encefálica/complicações , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Metilação de DNA , Células Endoteliais/metabolismo , Glucose , Heme Oxigenase (Desciclizante)/metabolismo , Hipóxia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/genética , Apneia Obstrutiva do Sono/metabolismo , Acidente Vascular Cerebral/complicações , Transativadores/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
20.
Nat Cell Biol ; 26(1): 86-99, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38172614

RESUMO

The Hippo pathway has important roles in organ development, tissue homeostasis and tumour growth. Its downstream effector TAZ is a transcriptional coactivator that promotes target gene expression through the formation of biomolecular condensates. However, the mechanisms that regulate the biophysical properties of TAZ condensates to enable Hippo signalling are not well understood. Here using chemical crosslinking combined with an unbiased proteomics approach, we show that FUS associates with TAZ condensates and exerts a chaperone-like effect to maintain their proper liquidity and robust transcriptional activity. Mechanistically, the low complexity sequence domain of FUS targets the coiled-coil domain of TAZ in a phosphorylation-regulated manner, which ensures the liquidity and dynamicity of TAZ condensates. In cells lacking FUS, TAZ condensates transition into gel-like or solid-like assembles with immobilized TAZ, which leads to reduced expression of target genes and inhibition of pro-tumorigenic activity. Thus, our findings identify a chaperone-like function of FUS in Hippo regulation and demonstrate that appropriate biophysical properties of transcriptional condensates are essential for gene activation.


Assuntos
Proteínas Serina-Treonina Quinases , Transativadores , Transativadores/genética , Transativadores/metabolismo , Ativação Transcricional , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Linhagem Celular Tumoral
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