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1.
J Gen Virol ; 105(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572740

RESUMO

The herpes simplex virus 1 (HSV1) virion host shutoff (vhs) protein is an endoribonuclease that regulates the translational environment of the infected cell, by inducing the degradation of host mRNA via cellular exonuclease activity. To further understand the relationship between translational shutoff and mRNA decay, we have used ectopic expression to compare HSV1 vhs (vhsH) to its homologues from four other alphaherpesviruses - varicella zoster virus (vhsV), bovine herpesvirus 1 (vhsB), equine herpesvirus 1 (vhsE) and Marek's disease virus (vhsM). Only vhsH, vhsB and vhsE induced degradation of a reporter luciferase mRNA, with poly(A)+ in situ hybridization indicating a global depletion of cytoplasmic poly(A)+ RNA and a concomitant increase in nuclear poly(A)+ RNA and the polyA tail binding protein PABPC1 in cells expressing these variants. By contrast, vhsV and vhsM failed to induce reporter mRNA decay and poly(A)+ depletion, but rather, induced cytoplasmic G3BP1 and poly(A)+ mRNA- containing granules and phosphorylation of the stress response proteins eIF2α and protein kinase R. Intriguingly, regardless of their apparent endoribonuclease activity, all vhs homologues induced an equivalent general blockade to translation as measured by single-cell puromycin incorporation. Taken together, these data suggest that the activities of translational arrest and mRNA decay induced by vhs are separable and we propose that they represent sequential steps of the vhs host interaction pathway.


Assuntos
Herpesvirus Humano 1 , Proteínas Virais , Proteínas Virais/genética , Proteínas Virais/metabolismo , Ribonucleases , DNA Helicases , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , RNA Helicases , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Herpesvirus Humano 1/genética , Endorribonucleases/metabolismo , Estabilidade de RNA , Vírion/genética , Vírion/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
2.
Nat Commun ; 15(1): 2857, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565848

RESUMO

PARP2 is a DNA-dependent ADP-ribosyl transferase (ARTs) enzyme with Poly(ADP-ribosyl)ation activity that is triggered by DNA breaks. It plays a role in the Base Excision Repair pathway, where it has overlapping functions with PARP1. However, additional roles for PARP2 have emerged in the response of cells to replication stress. In this study, we demonstrate that PARP2 promotes replication stress-induced telomere fragility and prevents telomere loss following chronic induction of oxidative DNA lesions and BLM helicase depletion. Telomere fragility results from the activity of the break-induced replication pathway (BIR). During this process, PARP2 promotes DNA end resection, strand invasion and BIR-dependent mitotic DNA synthesis by orchestrating POLD3 recruitment and activity. Our study has identified a role for PARP2 in the response to replication stress. This finding may lead to the development of therapeutic approaches that target DNA-dependent ART enzymes, particularly in cancer cells with high levels of replication stress.


Assuntos
Reparo do DNA , DNA , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , DNA/metabolismo , Dano ao DNA , DNA Helicases/genética , DNA Helicases/metabolismo , Telômero/genética , Telômero/metabolismo
3.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(4): 325-331, 2024 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-38599807

RESUMO

Objective: To analyze the clinical characteristics and prognosis of 17 patients with pathologically confirmed SMARCA4-deficient chest tumors. Methods: Seventeen patients with SMARCA4-deficient thoracic tumors diagnosed by pathology in the Affiliated Hospital of Jining Medical University from September 2021 to January 2023 were collected through Results Query System of Pathology Department, and the patients' general conditions, clinical symptoms, tumor markers, imaging features, treatment and regression were retrospectively analyzed, and literature review was performed. Results: A total of 17 patients were included in this study. Their clinical characteristics were characterized as follows: male/female=16/1, age 42-74 years, mean (64.0±5.7)years. Only 1 female had no clear smoking history, and 16 males had a smoking history, of whom 1 had 5 smoking pack-years, and the remaining 15 case had a smoking history of 20-100 smoking pack-years, with a mean of (68.5±44.5) smoking pack-years. Clinical symptoms were mainly cough and sputum, followed by chest tightness, hemoptysis and chest pain. Tumor markers CYFRA19-9 was elevated in 9 cases (3.79-16.61 ng/ml), CEA was elevated in 8 cases (5.37-295.93 ng/ml), and NSE was elevated in 6 cases (17.18-70.37 ng/ml). Imaging manifestations were intrapulmonary or mediastinal mass shadows, and the tumor involved the mediastinum in 9 cases, the upper lobe of the right lung in 6 cases, the upper lobe of the left lung in 5 cases, the lower lobe of the right lung in 3 cases, the lower lobe of the left lung in 3 cases; cervical or supraclavicular lymph node metastasis in 8 cases, pleural metastasis in 4 cases, hepatic metastasis in 3 cases, cerebral metastasis in 3 cases, bone metastasis in 2 cases, and subcutaneous metastasis in 1 case. Combining immuno-histochemistry and pathology, there were 6 cases of SMARCA4-deficient NSCLC and 11 cases of SMARCA4-deficient undifferentiated tumor. Eight patients were treated with platinum-contained chemotherapy agents, four of which were combined with immune checkpoint inhibitors, and one was treated with enzatinib; only one of the 9 patients achieved partial remission after treatment, and the remaining eight had progression of the tumors on chest CT after treatment. Five patients abandoned the treatment, and died in 6-month of follow-up. Three patients underwent surgery for resection, and there was no significant progression in the three patients in the 6 months of follow-up. Conclusions: Clinically, middle-aged and elderly men with a history of heavy smoking should be given high priority, especially in patients whose imaging mostly showed intrapulmonary, especially in upper lobes, and/or mediastinal masses, rapid lesion progression, and early distant metastasis, and who should be alerted to the possibility of SMARCA4-deficient thoracic tumors. Late clinical stage is a high risk factor for poor overall patient survival, and platinum-containing chemotherapy agents combined with immune checkpoint inhibitor therapy may be effective, and early surgery may improve patient prognosis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Neoplasias Torácicas , Pessoa de Meia-Idade , Idoso , Humanos , Masculino , Feminino , Adulto , Estudos Retrospectivos , Platina , Prognóstico , Neoplasias Torácicas/patologia , Neoplasias Pulmonares/patologia , Biomarcadores Tumorais , DNA Helicases , Proteínas Nucleares , Fatores de Transcrição
4.
Nat Commun ; 15(1): 3138, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38605034

RESUMO

The carboxy-terminus of the spliceosomal protein PRPF8, which regulates the RNA helicase Brr2, is a hotspot for mutations causing retinitis pigmentosa-type 13, with unclear role in human splicing and tissue-specificity mechanism. We used patient induced pluripotent stem cells-derived cells, carrying the heterozygous PRPF8 c.6926 A > C (p.H2309P) mutation to demonstrate retinal-specific endophenotypes comprising photoreceptor loss, apical-basal polarity and ciliary defects. Comprehensive molecular, transcriptomic, and proteomic analyses revealed a role of the PRPF8/Brr2 regulation in 5'-splice site (5'SS) selection by spliceosomes, for which disruption impaired alternative splicing and weak/suboptimal 5'SS selection, and enhanced cryptic splicing, predominantly in ciliary and retinal-specific transcripts. Altered splicing efficiency, nuclear speckles organisation, and PRPF8 interaction with U6 snRNA, caused accumulation of active spliceosomes and poly(A)+ mRNAs in unique splicing clusters located at the nuclear periphery of photoreceptors. Collectively these elucidate the role of PRPF8/Brr2 regulatory mechanisms in splicing and the molecular basis of retinal disease, informing therapeutic approaches.


Assuntos
Sítios de Splice de RNA , Retinite Pigmentosa , Spliceossomos , Humanos , Spliceossomos/genética , Spliceossomos/metabolismo , Proteômica , Splicing de RNA/genética , Processamento Alternativo/genética , RNA Nuclear Pequeno/genética , RNA Nuclear Pequeno/metabolismo , RNA Mensageiro/metabolismo , Mutação , DNA Helicases/metabolismo , Proteínas de Ligação a RNA/metabolismo
5.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(4): 480-485, 2024 Apr 10.
Artigo em Chinês | MEDLINE | ID: mdl-38565516

RESUMO

OBJECTIVE: To explore the clinical characteristics of 1q21.1 microdeletion by using single nucleotide polymorphism microarrays (SNP array). METHODS: Eighteen cases of 1q21.1 microdeletion syndrome diagnosed at the Longgang District Maternal and Child Health Care Hospital of Shenzhen City from June 2017 to December 2022 were selected as the study subjects. Clinical data of the patients were collected. Results of chromosomal karyotyping and SNP assay were retrospectively analyzed. RESULTS: Among the 18 cases with 1q21.1 microdeletions, 13 had a deletion between BP3 and BP4, 4 had a deletion between BP1/BP2 and BP4, whilst 1 had a proximal 1q21.1 deletion (between BP2 and BP3) involving the Thrombocytopenia-absent radius (TAR) region. The deletions had spanned from 360 kb to 3.9 Mb, which encompassed the GJA5, GJA8, CHD1L, RBM8AB and other morbid genes. In three families, the proband child has inherited the same 1q21.1 microdeletion from their parents, whose clinical phenotype was normal or slightly abnormal. The clinical phenotypes of 1q21.1 microdeletion had included cognitive or behavioral deficits in 9 cases (9/18, 50.0%), growth retardation in 8 cases (8/18, 44.4%), craniofacial deformities in 7 cases (7/18, 38.8%), cardiovascular malformations in 5 cases (5/18, 27.8%), and microcephaly in 3 cases (3/18, 16.7%). CONCLUSION: 1q21.1 microdeletion syndrome has incomplete penetrance and varied expression such as intellectual impairment, growth and development delay, and microcephaly, with a wide range of non-specific phenotypes.


Assuntos
Anormalidades Múltiplas , Deficiência Intelectual , Megalencefalia , Microcefalia , Criança , Humanos , Microcefalia/genética , Estudos Retrospectivos , Deleção Cromossômica , Fenótipo , Biologia Molecular , Deficiência Intelectual/genética , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Cromossomos Humanos Par 1
6.
Zhonghua Yi Xue Za Zhi ; 104(16): 1410-1417, 2024 Apr 23.
Artigo em Chinês | MEDLINE | ID: mdl-38644292

RESUMO

Objective: To investigate the genetic and expression characteristics of transcription factor IIH (TFIIH) in pre-initiationcomplex in prostate cancer (PCa) and its relationship with prostate cancer progression. Methods: Analyzing the expression characteristics and clinical signification of TFIIH subunits about 495 cases of PCa and 52 cases of adjacent cancer in The Cancer Genome Atlas-Prostate adenocarcinoma (TCGA-PRAD) database. PCa microarray chip was used to verify the correlation between the key factor General Transcription Factor IIH Subunit 4 (GTF2H4) in TFIIH and clinical features. Results: The 495 patients with PCa were (61.01±6.82) years old.The mRNA expression of ERCC3、GTF2H4 and MNAT1 were high in PCa tissues with GS≥8(P<0.05). The expression of GTF2H4 and MNAT1 were relevant to the pathological stages(P<0.05). High expression of GTF2H4 has higher biochemical recurrence (BCR) rate in PCa patients(HR=2.47, 95%CI:1.62-3.77, P<0.001), which has better predictive effect of BCR in PCa patients(The 3rd, 5th, and 7th year AUC all>0.7) than other subunits, and it has been verified in four additional databases. Single-factor Cox regression analysis showed that GTF2H4 were risk factors for BCR (HR=2.470, 95%CI:1.620-3.767, P<0.001) and GTF2H5 were protective factors(HR=0.506,95%CI: 0.336-0.762, P=0.001). The results of immunohistochemical staining showed that the protein expression of GTF2H4 was correlated with the clinical features of PCa patients.The differences of the above results were statistically significant. Conclusion: GTF2H4, the key factor of TFIIH, is highly expressed in PCa and indicates a poor prognosis.


Assuntos
Biologia Computacional , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Prognóstico , Pessoa de Meia-Idade , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , DNA Helicases/metabolismo , DNA Helicases/genética , Idoso , Fatores de Transcrição TFII/metabolismo , Fatores de Transcrição TFII/genética
7.
Int J Mol Sci ; 25(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38612449

RESUMO

Stress granules (SGs) are membraneless ribonucleoprotein (RNP)-based cellular foci formed in response to stress, facilitating cell survival by protecting against damage. Mammalian spermatogenesis should be maintained below body temperature for proper development, indicating its vulnerability to heat stress (HS). In this study, biotin tracer permeability assays showed that the inhibition of heat-induced SG assembly in the testis by 4-8 mg/kg cycloheximide significantly increased the percentage of seminiferous tubules with a damaged blood-testis barrier (BTB). Western blot results additionally revealed that the suppression of heat-induced SG assembly in Sertoli cell line, TM4 cells, by RNA inference of G3bp1/2 aggravated the decline in the BTB-related proteins ZO-1, ß-Catenin and Claudin-11, indicating that SGs could protect the BTB against damage caused by HS. The protein components that associate with SGs in Sertoli cells were isolated by sequential centrifugation and immunoprecipitation, and were identified by liquid chromatography with tandem mass spectrometry. Gene Ontology and KEGG pathway enrichment analysis revealed that their corresponding genes were mainly involved in pathways related to proteasomes, nucleotide excision repair, mismatch repair, and DNA replication. Furthermore, a new SG component, the ubiquitin associated protein 2 (UBAP2), was found to translocate to SGs upon HS in TM4 cells by immunofluorescence. Moreover, SG assembly was significantly diminished after UBAP2 knockdown by RNA inference during HS, suggesting the important role of UBAP2 in SG assembly. In addition, UBAP2 knockdown reduced the expression of ZO-1, ß-Catenin and Claudin-11, which implied its potential role in the function of the BTB. Overall, our study demonstrated the role of SGs in maintaining BTB functions during HS and identified a new component implicated in SG formation in Sertoli cells. These findings not only offer novel insights into the biological functions of SGs and the molecular mechanism of low fertility in males in summer, but also potentially provide an experimental basis for male fertility therapies.


Assuntos
Barreira Hematotesticular , DNA Helicases , Masculino , Animais , Camundongos , Proteínas de Ligação a Poli-ADP-Ribose , RNA Helicases , Proteínas com Motivo de Reconhecimento de RNA , Grânulos de Estresse , beta Catenina , RNA , Claudinas , Mamíferos
8.
Oncoimmunology ; 13(1): 2340154, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601319

RESUMO

Metabolism reprogramming within the tumor microenvironment (TME) can have a profound impact on immune cells. Identifying the association between metabolic phenotypes and immune cells in lung adenocarcinoma (LUAD) may reveal mechanisms of resistance to immune checkpoint inhibitors (ICIs). Metabolic phenotypes were classified by expression of metabolic genes. Somatic mutations and transcriptomic features were compared across the different metabolic phenotypes. The metabolic phenotype of LUAD is predominantly determined by reductase-oxidative activity and is divided into two categories: redoxhigh LUAD and redoxlow LUAD. Genetically, redoxhigh LUAD is mainly driven by mutations in KEAP1, STK11, NRF2, or SMARCA4. These mutations are more prevalent in redoxhigh LUAD (72.5%) compared to redoxlow LUAD (17.4%), whereas EGFR mutations are more common in redoxlow LUAD (19.0% vs. 0.7%). Single-cell RNA profiling of pre-treatment and post-treatment samples from patients receiving neoadjuvant chemoimmunotherapy revealed that tissue-resident memory CD8+ T cells are responders to ICIs. However, these cells are significantly reduced in redoxhigh LUAD. The redoxhigh phenotype is primarily attributed to tumor cells and is positively associated with mTORC1 signaling. LUAD with the redoxhigh phenotype demonstrates a lower response rate (39.1% vs. 70.8%, p = 0.001), shorter progression-free survival (3.3 vs. 14.6 months, p = 0.004), and overall survival (12.1 vs. 31.2 months, p = 0.022) when treated with ICIs. The redoxhigh phenotype in LUAD is predominantly driven by mutations in KEAP1, STK11, NRF2, and SMARCA4. This phenotype diminishes the number of tissue-resident memory CD8+ T cells and attenuates the efficacy of ICIs.


Assuntos
Quinases Proteína-Quinases Ativadas por AMP , Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Fator 2 Relacionado a NF-E2/genética , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Oxirredução , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Imunoterapia , Mutação , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Linfócitos T , Linfócitos T CD8-Positivos , Microambiente Tumoral/genética , DNA Helicases , Proteínas Nucleares , Fatores de Transcrição
9.
Cells ; 13(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38607030

RESUMO

Cockayne syndrome (CS) is a rare hereditary autosomal recessive disorder primarily caused by mutations in Cockayne syndrome protein A (CSA) or B (CSB). While many of the functions of CSB have been at least partially elucidated, little is known about the actual developmental dysregulation in this devasting disorder. Of particular interest is the regulation of cerebral development as the most debilitating symptoms are of neurological nature. We generated neurospheres and cerebral organoids utilizing Cockayne syndrome B protein (CSB)-deficient induced pluripotent stem cells derived from two patients with distinct severity levels of CS and healthy controls. The transcriptome of both developmental timepoints was explored using RNA-Seq and bioinformatic analysis to identify dysregulated biological processes common to both patients with CS in comparison to the control. CSB-deficient neurospheres displayed upregulation of the VEGFA-VEGFR2 signalling pathway, vesicle-mediated transport and head development. CSB-deficient cerebral organoids exhibited downregulation of brain development, neuron projection development and synaptic signalling. We further identified the upregulation of steroid biosynthesis as common to both timepoints, in particular the upregulation of the cholesterol biosynthesis branch. Our results provide insights into the neurodevelopmental dysregulation in patients with CS and strengthen the theory that CS is not only a neurodegenerative but also a neurodevelopmental disorder.


Assuntos
Síndrome de Cockayne , Células-Tronco Pluripotentes Induzidas , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , DNA Helicases/genética , Enzimas Reparadoras do DNA/metabolismo , Síndrome de Cockayne/genética , Síndrome de Cockayne/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Encéfalo/metabolismo , Organoides/metabolismo
10.
Proc Natl Acad Sci U S A ; 121(15): e2322563121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557192

RESUMO

Mammalian switch/sucrose nonfermentable (mSWI/SNF) ATPase degraders have been shown to be effective in enhancer-driven cancers by functioning to impede oncogenic transcription factor chromatin accessibility. Here, we developed AU-24118, an orally bioavailable proteolysis-targeting chimera (PROTAC) degrader of mSWI/SNF ATPases (SMARCA2 and SMARCA4) and PBRM1. AU-24118 demonstrated tumor regression in a model of castration-resistant prostate cancer (CRPC) which was further enhanced with combination enzalutamide treatment, a standard of care androgen receptor (AR) antagonist used in CRPC patients. Importantly, AU-24118 exhibited favorable pharmacokinetic profiles in preclinical analyses in mice and rats, and further toxicity testing in mice showed a favorable safety profile. As acquired resistance is common with targeted cancer therapeutics, experiments were designed to explore potential mechanisms of resistance that may arise with long-term mSWI/SNF ATPase PROTAC treatment. Prostate cancer cell lines exposed to long-term treatment with high doses of a mSWI/SNF ATPase degrader developed SMARCA4 bromodomain mutations and ABCB1 (ATP binding cassette subfamily B member 1) overexpression as acquired mechanisms of resistance. Intriguingly, while SMARCA4 mutations provided specific resistance to mSWI/SNF degraders, ABCB1 overexpression provided broader resistance to other potent PROTAC degraders targeting bromodomain-containing protein 4 and AR. The ABCB1 inhibitor, zosuquidar, reversed resistance to all three PROTAC degraders tested. Combined, these findings position mSWI/SNF degraders for clinical translation for patients with enhancer-driven cancers and define strategies to overcome resistance mechanisms that may arise.


Assuntos
Adenosina Trifosfatases , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Ratos , Camundongos , Animais , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Linhagem Celular , Cromatina , Mamíferos/genética , Antagonistas de Receptores de Andrógenos , DNA Helicases/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética
11.
Mol Cell ; 84(8): 1460-1474.e6, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38640894

RESUMO

DNA polymerase θ (Polθ) plays a central role in a DNA double-strand break repair pathway termed theta-mediated end joining (TMEJ). TMEJ functions by pairing short-sequence "microhomologies" (MHs) in single-stranded DNA at each end of a break and subsequently initiating DNA synthesis. It is not known how the Polθ helicase domain (HD) and polymerase domain (PD) operate to bring together MHs and facilitate repair. To resolve these transient processes in real time, we utilized in vitro single-molecule FRET approaches and biochemical analyses. We find that the Polθ-HD mediates the initial capture of two ssDNA strands, bringing them in close proximity. The Polθ-PD binds and stabilizes pre-annealed MHs to form a synaptic complex (SC) and initiate repair synthesis. Individual synthesis reactions show that Polθ is inherently non-processive, accounting for complex mutational patterns during TMEJ. Binding of Polθ-PD to stem-loop-forming sequences can substantially limit synapsis, depending on the available dNTPs and sequence context.


Assuntos
Quebras de DNA de Cadeia Dupla , DNA Polimerase Dirigida por DNA , DNA Polimerase Dirigida por DNA/metabolismo , Replicação do DNA , DNA de Cadeia Simples/genética , DNA Helicases/genética , Reparo do DNA por Junção de Extremidades
12.
J Cell Biol ; 223(7)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38652118

RESUMO

Chromatin-remodeling protein BRG1/SMARCA4 is pivotal for establishing oligodendrocyte (OL) lineage identity. However, its functions for oligodendrocyte-precursor cell (OPC) differentiation within the postnatal brain and during remyelination remain elusive. Here, we demonstrate that Brg1 loss profoundly impairs OPC differentiation in the brain with a comparatively lesser effect in the spinal cord. Moreover, BRG1 is critical for OPC remyelination after injury. Integrative transcriptomic/genomic profiling reveals that BRG1 exhibits a dual role by promoting OPC differentiation networks while repressing OL-inhibitory cues and proneuronal programs. Furthermore, we find that BRG1 interacts with EED/PRC2 polycomb-repressive-complexes to enhance H3K27me3-mediated repression at gene loci associated with OL-differentiation inhibition and neurogenesis. Notably, BRG1 depletion decreases H3K27me3 deposition, leading to the upregulation of BMP/WNT signaling and proneurogenic genes, which suppresses OL programs. Thus, our findings reveal a hitherto unexplored spatiotemporal-specific role of BRG1 for OPC differentiation in the developing CNS and underscore a new insight into BRG1/PRC2-mediated epigenetic regulation that promotes and safeguards OL lineage commitment and differentiation.


Assuntos
Diferenciação Celular , DNA Helicases , Proteínas Nucleares , Oligodendroglia , Complexo Repressor Polycomb 2 , Remielinização , Fatores de Transcrição , Animais , DNA Helicases/metabolismo , DNA Helicases/genética , Diferenciação Celular/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Remielinização/genética , Complexo Repressor Polycomb 2/metabolismo , Complexo Repressor Polycomb 2/genética , Oligodendroglia/metabolismo , Camundongos , Histonas/metabolismo , Histonas/genética , Neurogênese/genética , Epigênese Genética , Camundongos Endogâmicos C57BL , Células Precursoras de Oligodendrócitos/metabolismo
13.
PLoS One ; 19(4): e0298575, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38593124

RESUMO

Osteoarthritis (OA) is a widespread chronic, progressive, degenerative joint disease that causes pain and disability. Current treatments for OA have limited effectiveness and new biomarkers need to be identified. Bioinformatics analysis was conducted to explore differentially expressed genes and DNA repair/recombination protein 54 L (RAD54L) was selected. We firstly overexpressed RAD54L in interleukin-1ß (IL-1ß)-induced human articular chondrocytes or in OA rats to investigate its effect on OA. Chondrocyte viability and apoptotic rate were measured by Cell Counting Kit-8 and flow cytometry, respectively. Then we evaluated OA severity in vivo by Hematoxylin-eosin staining and Osteoarthritis Research Society International standards. The expression of inflammatory mediators was tested by enzyme-linked immunosorbent assay. Finally, western blot was performed to determine the relative expression level of hypoxia-inducible factors 1α (HIF-1α) and vascular endothelial growth factor (VEGF). Overexpression of RAD54L promoted cell viability and attenuated apoptosis in IL-1ß-induced human chondrocytes. A lower Osteoarthritis Research Society International score and a remarkable alleviation of chondrocyte disordering and infiltration of inflammatory cells were found in cartilage tissues of OA rats after overexpressing RAD54L. The inflammatory response induced by OA was decreased by RAD54L overexpression in vitro and in vivo. In addition, RAD54L overexpression decreased the relative expression level of HIF-1α and VEGF. Overexpression of RAD54L could attenuate OA by suppressing the HIF-1α/VEGF signaling pathway, indicating that RAD54L may be a potential treatment target for OA.


Assuntos
Cartilagem Articular , Osteoartrite , Animais , Humanos , Ratos , Apoptose , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Interleucina-1beta/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Signal Transduct Target Ther ; 9(1): 98, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609366

RESUMO

Evidence suggests associations between COVID-19 patients or vaccines and glycometabolic dysfunction and an even higher risk of the occurrence of diabetes. Herein, we retrospectively analyzed pancreatic lesions in autopsy tissues from 67 SARS-CoV-2 infected non-human primates (NHPs) models and 121 vaccinated and infected NHPs from 2020 to 2023 and COVID-19 patients. Multi-label immunofluorescence revealed direct infection of both exocrine and endocrine pancreatic cells by the virus in NHPs and humans. Minor and limited phenotypic and histopathological changes were observed in adult models. Systemic proteomics and metabolomics results indicated metabolic disorders, mainly enriched in insulin resistance pathways, in infected adult NHPs, along with elevated fasting C-peptide and C-peptide/glucose ratio levels. Furthermore, in elder COVID-19 NHPs, SARS-CoV-2 infection causes loss of beta (ß) cells and lower expressed-insulin in situ characterized by islet amyloidosis and necrosis, activation of α-SMA and aggravated fibrosis consisting of lower collagen in serum, an increase of pancreatic inflammation and stress markers, ICAM-1 and G3BP1, along with more severe glycometabolic dysfunction. In contrast, vaccination maintained glucose homeostasis by activating insulin receptor α and insulin receptor ß. Overall, the cumulative risk of diabetes post-COVID-19 is closely tied to age, suggesting more attention should be paid to blood sugar management in elderly COVID-19 patients.


Assuntos
COVID-19 , Diabetes Mellitus , Adulto , Animais , Humanos , Idoso , SARS-CoV-2 , Receptor de Insulina , Peptídeo C , DNA Helicases , Estudos Retrospectivos , Proteínas de Ligação a Poli-ADP-Ribose , RNA Helicases , Proteínas com Motivo de Reconhecimento de RNA , Glucose
15.
Cell Death Dis ; 15(4): 259, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609375

RESUMO

Radiotherapy effectiveness in breast cancer is limited by radioresistance. Nevertheless, the mechanisms behind radioresistance are not yet fully understood. RUVBL1 and RUVBL2, referred to as RUVBL1/2, are crucial AAA+ ATPases that act as co-chaperones and are connected to cancer. Our research revealed that RUVBL1, also known as pontin/TIP49, is excessively expressed in MMTV-PyMT mouse models undergoing radiotherapy, which is considered a murine spontaneous breast-tumor model. Our findings suggest that RUVBL1 enhances DNA damage repair and radioresistance in breast cancer cells both in vitro and in vivo. Mechanistically, we discovered that DTL, also known as CDT2 or DCAF2, which is a substrate adapter protein of CRL4, promotes the ubiquitination of RUVBL1 and facilitates its binding to RUVBL2 and transcription cofactor ß-catenin. This interaction, in turn, attenuates its binding to acetyltransferase Tat-interacting protein 60 (TIP60), a comodulator of nuclear receptors. Subsequently, ubiquitinated RUVBL1 promotes the transcriptional regulation of RUVBL1/2-ß-catenin on genes associated with the non-homologous end-joining (NHEJ) repair pathway. This process also attenuates TIP60-mediated H4K16 acetylation and the homologous recombination (HR) repair process. Expanding upon the prior study's discoveries, we exhibited that the ubiquitination of RUVBL1 by DTL advances the interosculation of RUVBL1/2-ß-catenin. And, it then regulates the transcription of NHEJ repair pathway protein. Resulting in an elevated resistance of breast cancer cells to radiation therapy. From the aforementioned, it is evident that targeting DTL-RUVBL1/2-ß-catenin provides a potential radiosensitization approach when treating breast cancer.


Assuntos
Neoplasias Mamárias Animais , beta Catenina , Animais , Camundongos , ATPases Associadas a Diversas Atividades Celulares/genética , beta Catenina/genética , DNA Helicases/genética , Regulação da Expressão Gênica , Ubiquitina , Ubiquitinação , Proteínas Nucleares
16.
Lupus Sci Med ; 11(1)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637124

RESUMO

BACKGROUND: Lupus nephritis (LN) is a complication of SLE characterised by immune dysfunction and oxidative stress (OS). Limited options exist for LN. We aimed to identify LN-related OS, highlighting the need for non-invasive diagnostic and therapeutic approaches. METHODS: LN-differentially expressed genes (DEGs) were extracted from Gene Expression Omnibus datasets (GSE32591, GSE112943 and GSE104948) and Molecular Signatures Database for OS-associated DEGs (OSEGs). Functional enrichment analysis was performed for OSEGs related to LN. Weighted gene co-expression network analysis identified hub genes related to OS-LN. These hub OSEGs were refined as biomarker candidates via least absolute shrinkage and selection operator. The predictive value was validated using receiver operating characteristic (ROC) curves and nomogram for LN prognosis. We evaluated LN immune cell infiltration using single-sample gene set enrichment analysis and CIBERSORT. Additionally, gene set enrichment analysis explored the functional enrichment of hub OSEGs in LN. RESULTS: The study identified four hub genes, namely STAT1, PRODH, TXN2 and SETX, associated with OS related to LN. These genes were validated for their diagnostic potential, and their involvement in LN pathogenesis was elucidated through ROC and nomogram. Additionally, alterations in immune cell composition in LN correlated with hub OSEG expression were observed. Immunohistochemical analysis reveals that the hub gene is most correlated with activated B cells and CD8 T cells. Finally, we uncovered that the enriched pathways of OSEGs were mainly involved in the PI3K-Akt pathway and the Janus kinase-signal transducer and activator of transcription pathway. CONCLUSION: These findings contribute to advancing our understanding of the complex interplay between OS, immune dysregulation and molecular pathways in LN, laying a foundation for the identification of potential diagnostic biomarkers and therapeutic targets.


Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Humanos , Nefrite Lúpica/diagnóstico , Nefrite Lúpica/genética , Fosfatidilinositol 3-Quinases , Estresse Oxidativo/genética , Aprendizado de Máquina , DNA Helicases , RNA Helicases , Enzimas Multifuncionais
17.
Invest Ophthalmol Vis Sci ; 65(3): 25, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38502138

RESUMO

Purpose: A molecular diagnosis is only made in a subset of individuals with nonisolated microphthalmia, anophthalmia, and coloboma (MAC). This may be due to underutilization of clinical (whole) exome sequencing (cES) and an incomplete understanding of the genes that cause MAC. The purpose of this study is to determine the efficacy of cES in cases of nonisolated MAC and to identify new MAC phenotypic expansions. Methods: We determined the efficacy of cES in 189 individuals with nonisolated MAC. We then used cES data, a validated machine learning algorithm, and previously published expression data, case reports, and animal models to determine which candidate genes were most likely to contribute to the development of MAC. Results: We found the efficacy of cES in nonisolated MAC to be between 32.3% (61/189) and 48.1% (91/189). Most genes affected in our cohort were not among genes currently screened in clinically available ophthalmologic gene panels. A subset of the genes implicated in our cohort had not been clearly associated with MAC. Our analyses revealed sufficient evidence to support low-penetrance MAC phenotypic expansions involving nine of these human disease genes. Conclusions: We conclude that cES is an effective means of identifying a molecular diagnosis in individuals with nonisolated MAC and may identify putatively damaging variants that would be missed if only a clinically available ophthalmologic gene panel was obtained. Our data also suggest that deleterious variants in BRCA2, BRIP1, KAT6A, KAT6B, NSF, RAC1, SMARCA4, SMC1A, and TUBA1A can contribute to the development of MAC.


Assuntos
Anoftalmia , Coloboma , Microftalmia , Animais , Humanos , Anoftalmia/diagnóstico , Anoftalmia/genética , Coloboma/diagnóstico , Coloboma/genética , Sequenciamento do Exoma , Microftalmia/diagnóstico , Microftalmia/genética , Algoritmos , DNA Helicases , Proteínas Nucleares , Fatores de Transcrição/genética , Histona Acetiltransferases
18.
Nat Commun ; 15(1): 2163, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461299

RESUMO

Recent development of new immune checkpoint inhibitors has been particularly successfully in cancer treatment, but still the majority patients fail to benefit. Converting resistant tumors to immunotherapy sensitive will provide a significant improvement in patient outcome. Here we identify Mi-2ß as a key melanoma-intrinsic effector regulating the adaptive anti-tumor immune response. Studies in genetically engineered mouse melanoma models indicate that loss of Mi-2ß rescues the immune response to immunotherapy in vivo. Mechanistically, ATAC-seq analysis shows that Mi-2ß controls the accessibility of IFN-γ-stimulated genes (ISGs). Mi-2ß binds to EZH2 and promotes K510 methylation of EZH2, subsequently activating the trimethylation of H3K27 to inhibit the transcription of ISGs. Finally, we develop an Mi-2ß-targeted inhibitor, Z36-MP5, which reduces Mi-2ß ATPase activity and reactivates ISG transcription. Consequently, Z36-MP5 induces a response to immune checkpoint inhibitors in otherwise resistant melanoma models. Our work provides a potential therapeutic strategy to convert immunotherapy resistant melanomas to sensitive ones.


Assuntos
DNA Helicases , Proteína Potenciadora do Homólogo 2 de Zeste , Evasão da Resposta Imune , Melanoma , Animais , Humanos , Camundongos , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Evasão da Resposta Imune/genética , Melanoma/tratamento farmacológico , Metilação , DNA Helicases/genética , DNA Helicases/metabolismo
19.
PLoS Biol ; 22(3): e3002552, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38502677

RESUMO

Impediments in replication fork progression cause genomic instability, mutagenesis, and severe pathologies. At stalled forks, RPA-coated single-stranded DNA (ssDNA) activates the ATR kinase and directs fork remodeling, 2 key early events of the replication stress response. RFWD3, a recently described Fanconi anemia (FA) ubiquitin ligase, associates with RPA and promotes its ubiquitylation, facilitating late steps of homologous recombination (HR). Intriguingly, RFWD3 also regulates fork progression, restart and stability via poorly understood mechanisms. Here, we used proteomics to identify putative RFWD3 substrates during replication stress in human cells. We show that RFWD3 interacts with and ubiquitylates the SMARCAL1 DNA translocase directly in vitro and following DNA damage in vivo. SMARCAL1 ubiquitylation does not trigger its subsequent proteasomal degradation but instead disengages it from RPA thereby regulating its function at replication forks. Proper regulation of SMARCAL1 by RFWD3 at stalled forks protects them from excessive MUS81-mediated cleavage in response to UV irradiation, thereby limiting DNA replication stress. Collectively, our results identify RFWD3-mediated SMARCAL1 ubiquitylation as a novel mechanism that modulates fork remodeling to avoid genome instability triggered by aberrant fork processing.


Assuntos
Replicação do DNA , DNA de Cadeia Simples , Humanos , DNA de Cadeia Simples/genética , Replicação do DNA/genética , Proteína de Replicação A/genética , Proteína de Replicação A/metabolismo , Ligação Proteica , Ubiquitinação , Dano ao DNA , Instabilidade Genômica , DNA Helicases/genética , DNA Helicases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
20.
BMC Cancer ; 24(1): 385, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38532312

RESUMO

Gliomas are the most common primary intracranial tumor worldwide. The maintenance of telomeres serves as an important biomarker of some subtypes of glioma. In order to investigate the biological role of RTEL1 in glioma. Relative telomere length (RTL) and RTEL1 mRNA was explored and regression analysis was performed to further examine the relationship of the RTL and the expression of RTEL1 with clinicopathological characteristics of glioma patients. We observed that high expression of RTEL1 is positively correlated with telomere length in glioma tissue, and serve as a poor prognostic factor in TERT wild-type patients. Further in vitro studies demonstrate that RTEL1 promoted proliferation, formation, migration and invasion ability of glioma cells. In addition, in vivo studies also revealed the oncogene role of RTEL1 in glioma. Further study using RNA sequence and phospho-specific antibody microarray assays identified JNK/ELK1 signaling was up-regulated by RTEL1 in glioma cells through ROS. In conclusion, our results suggested that RTEL1 promotes glioma tumorigenesis through JNK/ELK1 cascade and indicate that RTEL1 may be a prognostic biomarker in gliomas.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Glioma/patologia , Neoplasias Encefálicas/genética , Transformação Celular Neoplásica/genética , Oncogenes , Biomarcadores , Proliferação de Células , Proteínas Elk-1 do Domínio ets/genética , DNA Helicases/genética
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