RESUMO
Polypyrimidine tract-binding protein 1 (PTBP1) regulates numerous alternative splicing events during tumor progression and neurogenesis. Previously, PTBP1 downregulation was reported to convert astrocytes into functional neurons; however, how PTBP1 regulates astrocytic physiology remains unclear. In this study, we revealed that PTBP1 modulated glutamate uptake via ATP1a2, a member of Na+/K+-ATPases, and glutamate transporters in astrocytes. Ptbp1 knockdown altered mitochondrial function and energy metabolism, which involved PTBP1 regulating mitochondrial redox homeostasis via the succinate dehydrogenase (SDH)/Nrf2 pathway. The malfunction of glutamate transporters following Ptbp1 knockdown resulted in enhanced excitatory synaptic transmission in the cortex. Notably, we developed a biomimetic cationic triblock polypeptide system, i.e., polyethylene glycol44-polylysine30-polyleucine10 (PEG44-PLL30-PLLeu10) with astrocytic membrane coating to deliver Ptbp1 siRNA in vitro and in vivo, which approach allowed Ptbp1 siRNA to efficiently cross the blood-brain barrier and target astrocytes in the brain. Collectively, our findings suggest a framework whereby PTBP1 serves as a modulator in glutamate transport machinery, and indicate that biomimetic methodology is a promising route for in vivo siRNA delivery.
Assuntos
Astrócitos , Ácido Glutâmico , Ribonucleoproteínas Nucleares Heterogêneas , Homeostase , Fator 2 Relacionado a NF-E2 , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA Interferente Pequeno , Animais , Astrócitos/metabolismo , Ácido Glutâmico/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Fator 2 Relacionado a NF-E2/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Camundongos , Transdução de Sinais , Membrana Celular/metabolismo , Camundongos Endogâmicos C57BL , Masculino , Humanos , Mitocôndrias/metabolismoRESUMO
The therapeutic potential of suppressing polypyrimidine tract-binding protein 1 (Ptbp1) messenger RNA by viral transduction in a post-stroke dementia mouse model has not yet been examined. In this study, 3 days after cerebral ischemia, we injected a viral vector cocktail containing adeno-associated virus (AAV)-pGFAP-mCherry and AAV-pGFAP-CasRx (control vector) or a cocktail of AAV-pGFAP-mCherry and AAV-pGFAP-CasRx-SgRNA-(Ptbp1) (1:5, 1.0 × 1011 viral genomes) into post-stroke mice via the tail vein. We observed new mCherry/NeuN double-positive neuron-like cells in the hippocampus 56 days after cerebral ischemia. A portion of mCherry/GFAP double-positive astrocyte-like glia could have been converted into new mCherry/NeuN double-positive neuron-like cells with morphological changes. The new neuronal cells integrated into the dentate gyrus and recognition memory was significantly ameliorated. These results demonstrated that the in vivo conversion of hippocampal astrocyte-like glia into functional new neurons by the suppression of Ptbp1 might be a therapeutic strategy for post-stroke dementia.
Assuntos
Astrócitos , Isquemia Encefálica , Modelos Animais de Doenças , Ribonucleoproteínas Nucleares Heterogêneas , Hipocampo , Neurogênese , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Animais , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Astrócitos/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Camundongos , Isquemia Encefálica/metabolismo , Isquemia Encefálica/terapia , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Masculino , Neurônios/metabolismo , Memória , Camundongos Endogâmicos C57BL , Vetores Genéticos/genética , Vetores Genéticos/administração & dosagemRESUMO
BACKGROUND: Cervical cancer is the most common gynecological malignancy in the world and seriously threatens to women's lives and health. Polypyrimidine tract binding protein 1 (PTBP1), as an important splicing factor, has been identified as a proto-oncogene in several cancers, but its role and mechanism in cervical cancer remain poorly understood. Thus, our aim is to explore the impact of PTBP1 on proliferation, migration, apoptosis of cervical cancer cells, and its underlying mechanisms. METHODS: The biological functions in cervical cancer cells were determined using small interfering RNA (siRNA), agonist, Cell Counting Kit-8 (CCK-8), transwell, migration test, western blot, real-time-PCR, immunohistochemistry and immunofluorescence, respectively. RESULTS: The results indicated that PTBP1 was highly expressed in cervical cancer patients and cervical cancer cell lines compared to the normal group. Moreover, PTBP1 silencing significantly inhibited cell proliferation, and migration in both HeLa and SiHa cells. The PTBP1 silencing also induced mitochondrial apoptosis through upregulating Bax and mitochondrial apoptotic protein Cytochrome C, and downregulating B-Cell Leukemia/Lymphoma 2 (Bcl2) protein. Additionally, PTBP1 silencing induced autophagy by downregulating Sequestosome I (p62) and upregulating the ratio of Light chain 3-â ¡/Light chain 3-â (LC3-â ¡/LC3-â ). Mechanistically, we found that the Phosphoinositide 3-kinase (PI3K) agonist reversed the changes induced by PTBP1 silencing. CONCLUSIONS: Overall, PTBP1 silencing can induce cervical cancer cells apoptosis mainly through PI3K/AKT pathway and protective autophagy. This study provides preliminary evidence for PTBP1 as a therapeutic target or prognostic marker for cervical cancer.
Assuntos
Apoptose , Autofagia , Proliferação de Células , Ribonucleoproteínas Nucleares Heterogêneas , Fosfatidilinositol 3-Quinases , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Neoplasias do Colo do Útero , Humanos , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Feminino , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/metabolismo , Autofagia/genética , Apoptose/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Células HeLa , Inativação Gênica , Regulação Neoplásica da Expressão Gênica , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismoRESUMO
The N-terminal RNA recognition motif domain (RRM1) of polypyrimidine tract binding protein (PTB) forms an additional C-terminal helix α3, which docks to one edge of the ß-sheet upon binding to a stem-loop RNA containing a UCUUU pentaloop. Importantly, α3 does not contact the RNA. The α3 helix therefore represents an allosteric means to regulate the conformation of adjacent domains in PTB upon binding structured RNAs. Here we investigate the process of dynamic adaptation by stem-loop RNA and RRM1 using NMR and MD in order to obtain mechanistic insights on how this allostery is achieved. Relaxation data and NMR structure determination of the free protein show that α3 is partially ordered and interacts with the domain transiently. Stem-loop RNA binding quenches fast time scale dynamics and α3 becomes ordered, however microsecond dynamics at the protein-RNA interface is observed. MD shows how RRM1 binding to the stem-loop RNA is coupled to the stabilization of the C-terminal helix and helps to transduce differences in RNA loop sequence into changes in α3 length and order. IRES assays of full length PTB and a mutant with altered dynamics in the α3 region show that this dynamic allostery influences PTB function in cultured HEK293T cells.
Assuntos
Proteína de Ligação a Regiões Ricas em Polipirimidinas , Ligação Proteica , RNA , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/química , Humanos , RNA/química , RNA/metabolismo , Simulação de Dinâmica Molecular , Domínios Proteicos , Motivo de Reconhecimento de RNA , Regulação Alostérica , Dobramento de Proteína , Conformação de Ácido Nucleico , Sítios de LigaçãoRESUMO
Gene co-expression networks may encode hitherto inadequately recognized vulnerabilities for adult gliomas. By identifying evolutionally conserved gene co-expression modules around EGFR (EM) or PDGFRA (PM), we recently proposed an EM/PM classification scheme, which assigns IDH-wildtype glioblastomas (GBM) into the EM subtype committed in neural stem cell compartment, IDH-mutant astrocytomas and oligodendrogliomas into the PM subtype committed in early oligodendrocyte lineage. Here, we report the identification of EM/PM subtype-specific gene co-expression networks and the characterization of hub gene polypyrimidine tract-binding protein 1 (PTBP1) as a genomic alteration-independent vulnerability in IDH-wildtype GBM. Supervised by the EM/PM classification scheme, we applied weighted gene co-expression network analysis to identify subtype-specific global gene co-expression modules. These gene co-expression modules were characterized for their clinical relevance, cellular origin and conserved expression pattern during brain development. Using lentiviral vector-mediated constitutive or inducible knockdown, we characterized the effects of PTBP1 on the survival of IDH-wildtype GBM cells, which was complemented with the analysis of PTBP1-depedent splicing pattern and overexpression of splicing target neuron-specific CDC42 (CDC42-N) isoform. Transcriptomes of adult gliomas can be robustly assigned into 4 large gene co-expression modules that are prognostically relevant and are derived from either malignant cells of the EM/PM subtypes or tumor microenvironment. The EM subtype is associated with a malignant cell-intrinsic gene module involved in pre-mRNA splicing, DNA replication and damage response, and chromosome segregation, and a microenvironment-derived gene module predominantly involved in extracellular matrix organization and infiltrating immune cells. The PM subtype is associated with two malignant cell-intrinsic gene modules predominantly involved in transcriptional regulation and mRNA translation, respectively. Expression levels of these gene modules are independent prognostic factors and malignant cell-intrinsic gene modules are conserved during brain development. Focusing on the EM subtype, we identified PTBP1 as the most significant hub for the malignant cell-intrinsic gene module. PTBP1 is not altered in most glioma genomes. PTBP1 represses the conserved splicing of CDC42-N. PTBP1 knockdown or CDC42-N overexpression disrupts actin cytoskeleton dynamics, causing accumulation of reactive oxygen species and cell apoptosis. PTBP1-mediated repression of CDC42-N splicing represents a potential genomic alteration-independent, developmentally conserved vulnerability in IDH-wildtype GBM.
Assuntos
Glioblastoma , Ribonucleoproteínas Nucleares Heterogêneas , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Proteína cdc42 de Ligação ao GTP , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Humanos , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Proteína cdc42 de Ligação ao GTP/genética , Proteína cdc42 de Ligação ao GTP/metabolismo , Linhagem Celular Tumoral , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Redes Reguladoras de Genes , Regulação Neoplásica da Expressão Gênica , Splicing de RNA , Neurônios/metabolismo , Neurônios/patologiaRESUMO
BACKGROUND: Gastric cancer (GC) is a prevalent malignant tumor, and the RNA-binding protein polypyrimidine tract-binding protein 1 (PTBP1) has been identified as a crucial factor in various tumor types. Moreover, abnormal autophagy levels have been shown to significantly impact tumorigenesis and progression. Despite this, the precise regulatory mechanism of PTBP1 in autophagy regulation in GC remains poorly understood. METHODS: To assess the expression of PTBP1 in GC, we employed a comprehensive approach utilizing western blot, real-time quantitative polymerase chain reaction (RT-qPCR), and bioinformatics analysis. To further identify the downstream target genes that bind to PTBP1 in GC cells, we utilized RNA immunoprecipitation coupled with sequencing (si-PTBP1 RNA-seq). To evaluate the impact of PTBP1 on gastric carcinogenesis, we conducted CCK-8 assays, colony formation assays, and GC xenograft mouse model assays. Additionally, we utilized a transmission electron microscope, immunofluorescence, flow cytometry, western blot, RT-qPCR, and GC xenograft mouse model experiments to elucidate the specific mechanism underlying PTBP1's regulation of autophagy in GC. RESULTS: Our findings indicated that PTBP1 was significantly overexpressed in GC tissues compared with adjacent normal tissues. Silencing PTBP1 resulted in abnormal accumulation of autophagosomes, thereby inhibiting GC cell viability both in vitro and in vivo. Mechanistically, interference with PTBP1 promoted the stability of thioredoxin-interacting protein (TXNIP) mRNA, leading to increased TXNIP-mediated oxidative stress. Consequently, this impaired lysosomal function, ultimately resulting in blockage of autophagic flux. Furthermore, our results suggested that interference with PTBP1 enhanced the antitumor effects of chloroquine, both in vitro and in vivo. CONCLUSION: PTBP1 knockdown impairs GC progression by directly binding to TXNIP mRNA and promoting its expression. Based on these results, PTBP1 emerges as a promising therapeutic target for GC.
Assuntos
Autofagia , Proteínas de Transporte , Ribonucleoproteínas Nucleares Heterogêneas , Estresse Oxidativo , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Neoplasias Gástricas , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Autofagia/genética , Humanos , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Animais , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genética , Estresse Oxidativo/genética , Linhagem Celular Tumoral , Camundongos , Progressão da Doença , Camundongos Nus , Regulação Neoplásica da Expressão Gênica , Proliferação de Células/genética , Técnicas de Silenciamento de Genes , Camundongos Endogâmicos BALB C , MasculinoRESUMO
LncRNA plays a crucial role in cancer progression and targeting, but it has been difficult to identify the critical lncRNAs involved in colorectal cancer (CRC) progression. We identified FAM83H-AS1 as a tumor-promoting associated lncRNA using 21 pairs of stage IV CRC tissues and adjacent normal tissues. In vitro and in vivo experiments revealed that knockdown of FAM83H-AS1 in CRC cells inhibited tumor proliferation and metastasis, and vice versa. M6A modification is critical for FAM83H-AS1 RNA stability through the writer METTL3 and the readers IGF2BP2/IGFBP3. PTBP1-an RNA binding protein-is responsible for the FAM83H-AS1 function in CRC. T4 (1770-2440 nt) and T5 (2440-2743 nt) on exon 4 of FAM83H-AS1 provide a platform for PTBP1 RRM2 interactions. Our results demonstrated that m6A modification dysregulated the FAM83H-AS1 oncogenic role by phosphorylated PTBP1 on its RNA splicing effect. In patient-derived xenograft models, ASO-FAM83H-AS1 significantly suppressed the growth of gastrointestinal (GI) tumors, not only CRC but also GC and ESCC. The combination of ASO-FAM83H-AS1 and oxaliplatin/cisplatin significantly suppressed tumor growth compared with treatment with either agent alone. Notably, there was pathological complete response in all these three GI cancers. Our findings suggest that FAM83H-AS1 targeted therapy would benefit patients primarily receiving platinum-based therapy in GI cancers.
Assuntos
Proliferação de Células , Neoplasias Colorretais , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas , Metiltransferases , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA Longo não Codificante , Humanos , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , RNA Longo não Codificante/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Neoplasias Colorretais/metabolismo , Animais , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Camundongos , Metiltransferases/genética , Metiltransferases/metabolismo , Linhagem Celular Tumoral , Adenosina/análogos & derivados , Adenosina/metabolismo , Masculino , Feminino , Ensaios Antitumorais Modelo de Xenoenxerto , Camundongos Nus , Estabilidade de RNA , Movimento Celular , Camundongos Endogâmicos BALB C , Ribonucleosídeo Difosfato Redutase , Proteínas de Ligação a RNARESUMO
AIMS/HYPOTHESIS: The relationship between metabolic dysfunction-associated steatotic liver disease (MASLD) and type 2 diabetes mellitus, insulin resistance and the metabolic syndrome is well established. While zinc finger BED-type containing 3 (ZBED3) has been linked to type 2 diabetes mellitus and the metabolic syndrome, its role in MASLD remains unclear. In this study, we aimed to investigate the function of ZBED3 in the context of MASLD. METHODS: Expression levels of ZBED3 were assessed in individuals with MASLD, as well as in cellular and animal models of MASLD. In vitro and in vivo analyses were conducted using a cellular model of MASLD induced by NEFA and an animal model of MASLD induced by a high-fat diet (HFD), respectively, to investigate the role of ZBED3 in MASLD. ZBED3 expression was increased by lentiviral infection or tail-vein injection of adeno-associated virus. RNA-seq and bioinformatics analysis were employed to examine the pathways through which ZBED3 modulates lipid accumulation. Findings from these next-generation transcriptome sequencing studies indicated that ZBED3 controls SREBP1c (also known as SREBF1; a gene involved in fatty acid de novo synthesis); thus, co-immunoprecipitation and LC-MS/MS were utilised to investigate the molecular mechanisms by which ZBED3 regulates the sterol regulatory element binding protein 1c (SREBP1c). RESULTS: In this study, we found that ZBED3 was significantly upregulated in the liver of individuals with MASLD and in MASLD animal models. ZBED3 overexpression promoted NEFA-induced triglyceride accumulation in hepatocytes in vitro. Furthermore, the hepatocyte-specific overexpression of Zbed3 promoted hepatic steatosis. Conversely, the hepatocyte-specific knockout of Zbed3 resulted in resistance of HFD-induced hepatic steatosis. Mechanistically, ZBED3 interacts directly with polypyrimidine tract-binding protein 1 (PTBP1) and affects its binding to the SREBP1c mRNA precursor to regulate SREBP1c mRNA stability and alternative splicing. CONCLUSIONS/INTERPRETATION: This study indicates that ZBED3 promotes hepatic steatosis and serves as a critical regulator of the progression of MASLD. DATA AVAILABILITY: RNA-seq data have been deposited in the NCBI Gene Expression Omnibus ( www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE231875 ). MS proteomics data have been deposited to the ProteomeXchange Consortium via the iProX partner repository ( https://proteomecentral.proteomexchange.org/cgi/GetDataset?ID=PXD041743 ).
Assuntos
Fígado Gorduroso , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Animais , Humanos , Fígado Gorduroso/metabolismo , Masculino , Camundongos , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Dieta Hiperlipídica , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Camundongos Endogâmicos C57BL , Resistência à Insulina/fisiologia , Diabetes Mellitus Tipo 2/metabolismo , Síndrome Metabólica/metabolismo , Fígado/metabolismoRESUMO
AIMS: This study aimed to elucidate the biological roles and regulatory mechanisms of B-cell lymphoma 7 protein family member A (BCL7A) in acute myeloid leukemia (AML), particularly its interaction with polypyrimidine tract binding protein 1 (PTBP1) and the effects on cancer progression and drug resistance. METHODS: BCL7A expression levels were analyzed in AML tissues and cell lines, focusing on associations with promoter hypermethylation. Interaction with PTBP1 and effects of differential expression of BCL7A were examined in vitro and in vivo. The impacts on cell proliferation, cycle progression, apoptosis, and differentiation were studied. Additionally, the regulatory roles of BCL7A on interferon regulatory factor 7 (IRF7) and 3-hydroxy-3-methylglutaryl-CoA synthase 1 (HMGCS1) were assessed. RESULTS: BCL7A was downregulated in AML due to promoter hypermethylation and negatively regulated by PTBP1. Upregulation of BCL7A impeded AML cell growth, induced apoptosis, promoted cell differentiation, and decreased cell infiltration into lymph nodes, enhancing survival in mouse models. Overexpression of BCL7A upregulated IRF7 and downregulated HMGCS1, linking to reduced AML cell malignancy and decreased resistance to cytarabine. CONCLUSIONS: BCL7A acts as a tumor suppressor in AML, inhibiting malignant progression and enhancing drug sensitivity through the IRF7/HMGCS1 pathway. These findings suggest potential therapeutic targets for improving AML treatment outcomes.
Assuntos
Apoptose , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos , Ribonucleoproteínas Nucleares Heterogêneas , Leucemia Mieloide Aguda , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Animais , Camundongos , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proliferação de Células/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Metilação de DNA , Regiões Promotoras Genéticas , Progressão da Doença , Ensaios Antitumorais Modelo de Xenoenxerto , Masculino , Feminino , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Diferenciação Celular/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacosRESUMO
Abnormal epigenetic modifications are involved in the regulation of Warburg effect in tumor cells. Protein arginine methyltransferases (PRMTs) mediate arginine methylation and have critical functions in cellular responses. PRMTs are deregulated in a variety of cancers, but their precise roles in Warburg effect in cancer is largely unknown. Experiments from the current study showed that PRMT1 was highly expressed under conditions of glucose sufficiency. PRMT1 induced an increase in the PKM2/PKM1 ratio through upregulation of PTBP1, in turn, promoting aerobic glycolysis in non-small cell lung cancer (NSCLC). The PRMT1 level in p53-deficient and p53-mutated NSCLC remained relatively unchanged while the expression was reduced in p53 wild-type NSCLC under conditions of glucose insufficiency. Notably, p53 activation under glucose-deficient conditions could suppress USP7 and further accelerate the polyubiquitin-dependent degradation of PRMT1. Melatonin, a hormone that inhibits glucose intake, markedly suppressed cell proliferation of p53 wild-type NSCLC, while a combination of melatonin and the USP7 inhibitor P5091 enhanced the anticancer activity in p53-deficient NSCLC. Our collective findings support a role of PRMT1 in the regulation of Warburg effect in NSCLC. Moreover, combination treatment with melatonin and the USP7 inhibitor showed good efficacy, providing a rationale for the development of PRMT1-based therapy to improve p53-deficient NSCLC outcomes.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Proteínas de Membrana , Proteína-Arginina N-Metiltransferases , Proteínas de Ligação a Hormônio da Tireoide , Hormônios Tireóideos , Proteína Supressora de Tumor p53 , Efeito Warburg em Oncologia , Proteína-Arginina N-Metiltransferases/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Humanos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/tratamento farmacológico , Efeito Warburg em Oncologia/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Hormônios Tireóideos/metabolismo , Linhagem Celular Tumoral , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Proliferação de Células/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genética , Peptidase 7 Específica de Ubiquitina/metabolismo , Peptidase 7 Específica de Ubiquitina/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Animais , Glicólise/efeitos dos fármacos , Camundongos Nus , Glucose/metabolismo , Camundongos , Regulação Neoplásica da Expressão Gênica , Células A549 , Proteína de Ligação a Regiões Ricas em PolipirimidinasRESUMO
Background: Cisplatin (DDP) based combination chemotherapy is a vital method for the treatment of bladder cancer (BLca). Chemoresistance easily occurs in the course of cisplatin chemotherapy, which is one of the important reasons for the unfavorable prognosis of BLca patients. Circular RNAs (circRNAs) are widely recognized for their role in the development and advancement of BLca. Nevertheless, the precise role of circRNAs in DDP resistance for BLca remains unclear. Methods: To study the properties of circATIC, sanger sequencing, agarose gel electrophoresis and treatment with RNase R/Actinomycin D were utilized. RT-qPCR assay was utilized to assess the expression levels of circRNA, miRNA and mRNA in BLca tissues and cells. Functional experiments were conducted to assess the function of circATIC in BLca progression and chemosensitivity in vitro. Various techniques such as FISH, Dual-luciferase reporter assay, TRAP, RNA digestion assay, RIP and ChIRP assay were used to investigate the relationships between PTBP1, circATIC, miR-1247-5p and RCC2. Orthotopic bladder cancer model, xenograft subcutaneous tumor model and xenograft lung metastasis tumor model were performed to indicate the function and mechanism of circATIC in BLca progression and chemosensitivity in vivo. Results: In our study, we observed that circATIC expression was significantly enhanced in BLca tissues and cells and DDP resistant cells. Patients with higher circATIC expression have larger tumor diameter, higher incidence of postoperative metastasis and lower overall survival rate. Further experiments showed that circATIC accelerated BLca cell growth and metastasis and induced DDP resistance. Mechanistically, alternative splicing enzyme PTBP1 mediated the synthesis of circATIC. circATIC could enhance RCC2 mRNA stability via sponging miR-1247-5p or constructing a circATIC/LIN28A/RCC2 RNA-protein ternary complex. Finally, circATIC promotes RCC2 expression to enhance Epithelial-Mesenchymal Transition (EMT) progression and activate JNK signal pathway, thus strengthening DDP resistance in BLca cells. Conclusion: Our study demonstrated that circATIC promoted BLca progression and DDP resistance, and could serve as a potential target for BLca treatment.
Assuntos
Cisplatino , Resistencia a Medicamentos Antineoplásicos , Ribonucleoproteínas Nucleares Heterogêneas , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA Circular , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/genética , Humanos , RNA Circular/genética , RNA Circular/metabolismo , Cisplatino/uso terapêutico , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Animais , Linhagem Celular Tumoral , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , MicroRNAs/genética , Masculino , Feminino , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Camundongos Endogâmicos BALB C , Proliferação de Células/efeitos dos fármacosRESUMO
BACKGROUND: Dilated cardiomyopathy is characterized by left ventricular dilation and continuous systolic dysfunction. Mitochondrial impairment is critical in dilated cardiomyopathy; however, the underlying mechanisms remain unclear. Here, we explored the cardioprotective role of a heart-enriched long noncoding RNA, the dilated cardiomyopathy repressive transcript (DCRT), in maintaining mitochondrial function. METHODS: The DCRT knockout (DCRT-/-) mice and DCRT knockout cells were developed using CRISPR-Cas9 technology. Cardiac-specific DCRT transgenic mice were generated using α-myosin heavy chain promoter. Chromatin coimmunoprecipitation, RNA immunoprecipitation, Western blot, and isoform sequencing were performed to investigate the underlying mechanisms. RESULTS: We found that the long noncoding RNA DCRT was highly enriched in the normal heart tissues and that its expression was significantly downregulated in the myocardium of patients with dilated cardiomyopathy. DCRT-/- mice spontaneously developed cardiac dysfunction and enlargement with mitochondrial impairment. DCRT transgene or overexpression with the recombinant adeno-associated virus system in mice attenuated cardiac dysfunction induced by transverse aortic constriction treatment. Mechanistically, DCRT inhibited the third exon skipping of NDUFS2 (NADH dehydrogenase ubiquinone iron-sulfur protein 2) by directly binding to PTBP1 (polypyrimidine tract binding protein 1) in the nucleus of cardiomyocytes. Skipping of the third exon of NDUFS2 induced mitochondrial dysfunction by competitively inhibiting mitochondrial complex I activity and binding to PRDX5 (peroxiredoxin 5) and suppressing its antioxidant activity. Furthermore, coenzyme Q10 partially alleviated mitochondrial dysfunction in cardiomyocytes caused by DCRT reduction. CONCLUSIONS: Our study revealed that the loss of DCRT contributed to PTBP1-mediated exon skipping of NDUFS2, thereby inducing cardiac mitochondrial dysfunction during dilated cardiomyopathy development, which could be partially treated with coenzyme Q10 supplementation.
Assuntos
Processamento Alternativo , Cardiomiopatia Dilatada , Ribonucleoproteínas Nucleares Heterogêneas , Camundongos Knockout , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA Longo não Codificante , Animais , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/patologia , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Camundongos , Humanos , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Masculino , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Mitocôndrias Cardíacas/genética , Camundongos TransgênicosRESUMO
Coronary artery calcification (CAC) is a hallmark event in the pathogenesis of cardiovascular disease, involving the phenotypic transformation of vascular smooth muscle cells (VSMC) towards an osteogenic state. Despite this understanding, the molecular mechanisms governing the VSMC osteogenic switch remain incompletely elucidated. Here, we sought to examine the potential role of circular RNA (circRNA) in the context of CAC. Through transcriptome analysis of circRNA-seq, we identified circTOP1 as a potential candidate circRNA in individuals with CAC. Furthermore, we observed that overexpression of circTOP1 exacerbated vascular calcification in a CAC model. Subsequent pull-down assays revealed an interaction between circTOP1 and PTBP1, a putative target gene of circTOP1 in the context of CAC. In both in vivo and in vitro experiments, we observed heightened expression of circTOP1 and PTBP1 in the CAC model, and noted that reducing circTOP1 expression effectively reduced calcium salt deposits and mineralized nodules in model mice. Additionally, in vitro experiments demonstrated that overexpression of PTBP1 reversed the weakening of signaling caused by silencing circTOP1, thereby exacerbating the osteogenic transition and calcification of VSMC. Collectively, our findings suggested that circTOP1 promotes CAC by modulating PTBP1 expression to mediate VSMC transdifferentiation.
Assuntos
Ribonucleoproteínas Nucleares Heterogêneas , Músculo Liso Vascular , Miócitos de Músculo Liso , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA Circular , Calcificação Vascular , Animais , Humanos , Masculino , Camundongos , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/patologia , Doença da Artéria Coronariana/metabolismo , Vasos Coronários/patologia , Vasos Coronários/metabolismo , Progressão da Doença , Regulação da Expressão Gênica/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Osteogênese/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Calcificação Vascular/genética , Calcificação Vascular/patologia , Calcificação Vascular/metabolismoRESUMO
BACKGROUND: The present study aimed to explore the regulatory effects of artesunate on macrophage polarization in sepsis. METHODS: Cell models and mice models were established using lipopolysaccharide (LPS), followed by treatment with various concentrations of artesunate. The phenotype of the macrophages was determined by flow cytometry. RNA immunoprecipitation was used to confirm the binding between MALAT1 and polypyrimidine tract-binding protein 1 (PTBP1), as well as between PTBP1 and interferon-induced helicase C domain-containing protein 1 (IFIH1). RESULTS: Treatment with artesunate inhibited M1 macrophage polarization in Kupffer cells subjected to LPS stimulation by downregulating MALAT1. Furthermore, MALAT1 abolished the inhibitory effect of artesunate on M1 macrophage polarization by recruiting PTBP1 to promote IFIH. In vivo experiments confirmed that artesunate alleviated septic liver injury by affecting macrophage polarization via MALAT1. CONCLUSION: The present study showed that artesunate alleviates LPS-induced sepsis in Kupffer cells by regulating macrophage polarization via the lncRNA MALAT1/PTBP1/IFIH1 axis.
Assuntos
Artesunato , Células de Kupffer , Lipopolissacarídeos , Macrófagos , RNA Longo não Codificante , Sepse , Artesunato/farmacologia , Artesunato/uso terapêutico , Animais , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Camundongos , Sepse/tratamento farmacológico , Sepse/complicações , Células de Kupffer/efeitos dos fármacos , Células de Kupffer/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genéticaRESUMO
BACKGROUND: The functional coupling between alternative pre-mRNA splicing (AS) and the mRNA quality control mechanism called nonsense-mediated decay (NMD) can modulate transcript abundance. Previous studies have identified several examples of such a regulation in developing neurons. However, the systems-level effects of AS-NMD in this context are poorly understood. RESULTS: We developed an R package, factR2, which offers a comprehensive suite of AS-NMD analysis functions. Using this tool, we conducted a longitudinal analysis of gene expression in pluripotent stem cells undergoing induced neuronal differentiation. Our analysis uncovers hundreds of AS-NMD events with significant potential to regulate gene expression. Notably, this regulation is significantly overrepresented in specific functional groups of developmentally downregulated genes. Particularly strong association with gene downregulation is detected for alternative cassette exons stimulating NMD upon their inclusion into mature mRNA. By combining bioinformatic analyses with CRISPR/Cas9 genome editing and other experimental approaches we show that NMD-stimulating cassette exons regulated by the RNA-binding protein PTBP1 dampen the expression of their genes in developing neurons. We also provided evidence that the inclusion of NMD-stimulating cassette exons into mature mRNAs is temporally coordinated with NMD-independent gene repression mechanisms. CONCLUSIONS: Our study provides an accessible workflow for the discovery and prioritization of AS-NMD targets. It further argues that the AS-NMD pathway plays a widespread role in developing neurons by facilitating the downregulation of functionally related non-neuronal genes.
Assuntos
Processamento Alternativo , Regulação para Baixo , Neurônios , Degradação do RNAm Mediada por Códon sem Sentido , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Animais , Camundongos , Neurônios/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Éxons , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Diferenciação Celular/genética , Neurogênese/genéticaRESUMO
Coordination of neuronal differentiation with expansion of the neuroepithelial/neural progenitor cell (NEPC/NPC) pool is essential in early brain development. Our in vitro and in vivo studies identify independent and opposing roles for two neural-specific and differentially expressed non-coding RNAs derived from the same locus: the evolutionarily conserved lncRNA Rncr3 and the embedded microRNA miR124a-1. Rncr3 regulates NEPC/NPC proliferation and controls the biogenesis of miR124a, which determines neuronal differentiation. Rncr3 conserved exons 2/3 are cytosine methylated and bound by methyl-CpG binding protein MeCP2, which restricts expression of miR124a embedded in exon 4 to prevent premature neuronal differentiation, and to orchestrate proper brain growth. MeCP2 directly binds cytosine-methylated Rncr3 through previously unrecognized lysine residues and suppresses miR124a processing by recruiting PTBP1 to block access of DROSHA-DGCR8. Thus, miRNA processing is controlled by lncRNA m5C methylation along with the defined m5C epitranscriptomic RNA reader protein MeCP2 to coordinate brain development.
Assuntos
Proteína 2 de Ligação a Metil-CpG , MicroRNAs , Células-Tronco Neurais , Neurogênese , RNA Longo não Codificante , MicroRNAs/metabolismo , MicroRNAs/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Proteína 2 de Ligação a Metil-CpG/genética , Neurogênese/genética , Animais , Camundongos , RNA Longo não Codificante/metabolismo , RNA Longo não Codificante/genética , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/citologia , Encéfalo/metabolismo , Encéfalo/embriologia , Humanos , Diferenciação Celular , Metilação de DNA , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proliferação de Células , Camundongos Endogâmicos C57BL , 5-Metilcitosina/metabolismo , 5-Metilcitosina/análogos & derivados , Masculino , Éxons/genética , Neurônios/metabolismo , Ribonuclease IIIAssuntos
Hemangioendotelioma , Proteínas de Fusão Oncogênica , Transativadores , Humanos , Hemangioendotelioma/genética , Hemangioendotelioma/patologia , Transativadores/genética , Proteínas de Fusão Oncogênica/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Feminino , Masculino , Ribonucleoproteínas Nucleares Heterogêneas/genética , Diferenciação Celular/genética , Fatores de Transcrição/genética , Proteínas de Ligação a DNA/genéticaRESUMO
PTBP1 is an oncogene that regulates the splicing of precursor mRNA. However, the relationship between PTBP1 expression and gene methylation, cancer prognosis, and tumor microenvironment remains unclear. The expression profiles of PTBP1 across various cancers were derived from the TCGA, as well as the GTEx and CGGA databases. The CGGA mRNA_325, CGGA mRNA_301, and CGGA mRNA_693 datasets were utilized as validation cohorts. Immune cell infiltration scores were approximated using the TIMER 2.0 tool. Functional enrichment analysis for groups with high and low PTBP1 expression was conducted using Gene Set Enrichment Analysis (GSEA). Methylation data were predominantly sourced from the SMART and Mexpress databases. Linked-omics analysis was employed to perform functional enrichment analysis of genes related to PTBP1 methylation, as well as to conduct protein functional enrichment analysis. Single-cell transcriptome analysis and spatial transcriptome analysis were carried out using Seurat version 4.10. Compared to normal tissues, PTBP1 is significantly overexpressed and hypomethylated in various cancers. It is implicated in prognosis, immune cell infiltration, immune checkpoint expression, genomic variation, tumor neoantigen load, and tumor mutational burden across a spectrum of cancers, with particularly notable effects in low-grade gliomas. In the context of gliomas, PTBP1 expression correlates with WHO grade and IDH1 mutation status. PTBP1 expression and methylation play an important role in a variety of cancers. PTBP1 can be used as a marker of inflammation, progression and prognosis in gliomas.
Assuntos
Biomarcadores Tumorais , Regulação Neoplásica da Expressão Gênica , Glioma , Ribonucleoproteínas Nucleares Heterogêneas , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Microambiente Tumoral , Humanos , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Prognóstico , Biomarcadores Tumorais/genética , Glioma/genética , Glioma/patologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia , Metilação de DNA , Perfilação da Expressão Gênica , Inflamação/genética , Transcriptoma , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/mortalidade , Progressão da Doença , MultiômicaRESUMO
The role of circular RNAs (circRNAs) in glucose metabolism in pancreatic duct adenocarcinoma (PDAC) remains elusive. Through RNA sequencing of cells cultured under conditions of glucose deprivation, we identified hsa_circ_0007590. Sanger sequencing and RNase R and Act D treatments were performed to confirm the circular RNA features of hsa_circ_0007590. RNA in situ hybridization (RNA-ISH) and quantitative reverse transcription PCR (qRT-PCR) were used to estimate hsa_circ_0007590 expression in PDAC clinical specimens and cell lines. hsa_circ_0007590 expression was higher in PDAC patients and closely related to the clinicopathological characteristics of the disease. Cytoplasmânuclear fractionation and FISH assays demonstrated that hsa_circ_0007590 was located in the nucleus. Gain-of-function and loss-of-function assays were performed to assess the biological behaviors of PDAC cells. Seahorse XF assays were performed to validate the Warburg effect. hsa_circ_0007590 facilitated the proliferation, migration, and invasion of PDAC cells and promoted the Warburg effect. Mass spectrometry, RNA pulldown, RNA immunoprecipitation (RIP), RNA m6A quantification, m6A dot blot, MeRIP, and Western blotting were conducted to investigate the detailed mechanism through which hsa_circ_0007590 produces these effects. Mechanistically, hsa_circ_0007590 targeted PTBP1 and increased the expression of the m6A reader protein YTHDF2, leading to PTEN mRNA degradation and PI3K/AKT/mTOR pathway activation. Overall, hsa_circ_0007590, which targets PTBP1, reprograms glucose metabolism by attenuating the stability of m6A-modified PTEN mRNA and holds potential promise as a therapeutic target for PDAC.
Assuntos
Carcinoma Ductal Pancreático , Glucose , Ribonucleoproteínas Nucleares Heterogêneas , PTEN Fosfo-Hidrolase , Neoplasias Pancreáticas , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA Circular , Humanos , PTEN Fosfo-Hidrolase/metabolismo , PTEN Fosfo-Hidrolase/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , RNA Circular/genética , RNA Circular/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Glucose/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Camundongos , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Animais , Feminino , Linhagem Celular Tumoral , Estabilidade de RNA , Pessoa de Meia-IdadeRESUMO
Development of embryonic stem cells (ESCs) into neurons requires intricate regulation of transcription, splicing, and translation, but how these processes interconnect is not understood. We found that polypyrimidine tract binding protein 1 (PTBP1) controls splicing of DPF2, a subunit of BRG1/BRM-associated factor (BAF) chromatin remodeling complexes. Dpf2 exon 7 splicing is inhibited by PTBP1 to produce the DPF2-S isoform early in development. During neuronal differentiation, loss of PTBP1 allows exon 7 inclusion and DPF2-L expression. Different cellular phenotypes and gene expression programs were induced by these alternative DPF2 isoforms. We identified chromatin binding sites enriched for each DPF2 isoform, as well as sites bound by both. In ESC, DPF2-S preferential sites were bound by pluripotency factors. In neuronal progenitors, DPF2-S sites were bound by nuclear factor I (NFI), while DPF2-L sites were bound by CCCTC-binding factor (CTCF). DPF2-S sites exhibited enhancer modifications, while DPF2-L sites showed promoter modifications. Thus, alternative splicing redirects BAF complex targeting to impact chromatin organization during neuronal development.