Similar Datasets
Project description:Mutations in the RNA splicing factor SF3B1 are common across hematologic and solid cancers and result in widespread alterations in splicing but therapeutic means to correct this mis-splicing do not exist. Here we utilize synthetic introns uniquely responsive to mutant SF3B1 to identify trans factors required for aberrant mutant SF3B1 splicing activity. This revealed the G-patch domain containing protein GPATCH8 as required for mutant SF3B1-induced splicing alterations and impaired hematopoiesis. GPATCH8 is involved in quality control of branchpoint selection, interacts with the RNA helicase DHX15, and functionally opposes SUGP1, a G-patch protein recently implicated in SF3B1 mutant diseases. Silencing of GPATCH8 corrected one-third of mutant SF3B1 splicing defects and was sufficient to improve hematopoiesis in SF3B1 mutant mouse and human cells. These data identify GPATCH8 as a novel splicing factor required for mis-splicing by mutant SF3B1 and the therapeutic impact of correcting aberrant splicing in SF3B1 mutant cancers.
2023-09-01 | GSE242093 | GEO
Project description:Mutations in the RNA splicing factor SF3B1 are common across hematologic and solid cancers and result in widespread alterations in splicing but therapeutic means to correct this mis-splicing do not exist. Here we utilize synthetic introns uniquely responsive to mutant SF3B1 to identify trans factors required for aberrant mutant SF3B1 splicing activity. This revealed the G-patch domain containing protein GPATCH8 as required for mutant SF3B1-induced splicing alterations and impaired hematopoiesis. GPATCH8 is involved in quality control of branchpoint selection, interacts with the RNA helicase DHX15, and functionally opposes SUGP1, a G-patch protein recently implicated in SF3B1 mutant diseases. Silencing of GPATCH8 corrected one-third of mutant SF3B1 splicing defects and was sufficient to improve hematopoiesis in SF3B1 mutant mouse and human cells. These data identify GPATCH8 as a novel splicing factor required for mis-splicing by mutant SF3B1 and the therapeutic impact of correcting aberrant splicing in SF3B1 mutant cancers.
2023-09-01 | GSE242092 | GEO
Project description:Mutations in the RNA splicing factor SF3B1 are common across hematologic and solid cancers and result in widespread alterations in splicing but therapeutic means to correct this mis-splicing do not exist. Here we utilize synthetic introns uniquely responsive to mutant SF3B1 to identify trans factors required for aberrant mutant SF3B1 splicing activity. This revealed the G-patch domain containing protein GPATCH8 as required for mutant SF3B1-induced splicing alterations and impaired hematopoiesis. GPATCH8 is involved in quality control of branchpoint selection, interacts with the RNA helicase DHX15, and functionally opposes SUGP1, a G-patch protein recently implicated in SF3B1 mutant diseases. Silencing of GPATCH8 corrected one-third of mutant SF3B1 splicing defects and was sufficient to improve hematopoiesis in SF3B1 mutant mouse and human cells. These data identify GPATCH8 as a novel splicing factor required for mis-splicing by mutant SF3B1 and the therapeutic impact of correcting aberrant splicing in SF3B1 mutant cancers.
2024-03-20 | GSE262021 | GEO
Project description:Synthetic Introns Identify GPATCH8 as Required for Mis-splicing by SF3B1 Mutations
| PRJNA1011318 | ENA
Project description:Synthetic Introns Identify GPATCH8 as Required for Mis-splicing by SF3B1 Mutations [TRIBE-seq]
| PRJNA1011321 | ENA
Project description:Synthetic Introns Identify GPATCH8 as Required for Mis-splicing by SF3B1 Mutations [RNA-seq]
| PRJNA1011320 | ENA
Project description:Synthetic Introns Identify GPATCH8 as Required for Mis-splicing by SF3B1 Mutations [RNA-Seq 2]
| PRJNA1090048 | ENA
Project description:Splicing factor SF3B1 mutations are frequent somatic lesions in myeloid neoplasms that transform hematopoietic stem cells (HSCs) by inducing mis-splicing of target genes. However, the molecular and functional consequences of SF3B1 mutations in human HSCs and progenitors (HSPCs) remain unclear. Here, we identify the mis-splicing program in human HSPCs as a targetable vulnerability by precise gene editing of SF3B1 K700E mutations in primary CD34+ cells. Mutant SF3B1 induced pervasive mis-splicing and reduced expression of genes regulating mitosis and genome maintenance leading to altered differentiation, delayed G2/M progression, and profound sensitivity to CHK1 inhibition (CHK1i). Mis-splicing or reduced expression of mitotic regulators BUBR1 and CDC27 delayed G2/M transit and promoted CHK1i sensitivity. Clinical CHK1i prexasertib selectively targeted SF3B1-mutant immunophenotypic HSCs and abrogated engraftment in vivo. These findings identify mis-splicing of mitotic regulators in SF3B1-mutant HSPCs as a targetable vulnerability engaged by pharmacological CHK1 inhibition. Significance: In this study, we engineer precise SF3B1 mutations in human HSPCs and identify CHK1 inhibition as a selective vulnerability promoted by mis-splicing of mitotic regulators. These findings uncover the mis-splicing program induced by mutant SF3B1 in human HSPCs and show that it can be therapeutically targeted by clinical CHK1 inhibitors.
| S-EPMC11369594 | biostudies-literature
Project description:Transcription-associated cyclin-dependent kinases (CDKs) regulate the transcription cycle through sequential phosphorylation of RNA polymerase II (RNAPII). Herein, we report that dual inhibition of the highly homologous CDK12 and CDK13 impairs splicing of a subset of promoter-proximal introns characterized by weak 3' splice sites located at larger distance from the branchpoint. Nascent transcript analysis indicated that these introns are selectively retained upon pharmacological inhibition of CDK12/13 with respect to downstream introns of the same pre-mRNAs. Retention of these introns was also triggered by pladienolide B (PdB), an inhibitor of the U2 small nucelar ribonucleoprotein (snRNP) factor SF3B1 that recognizes the branchpoint. CDK12/13 activity promotes the interaction of SF3B1 with RNAPII phosphorylated on Ser2, and disruption of this interaction by treatment with the CDK12/13 inhibitor THZ531 impairs the association of SF3B1 with chromatin and its recruitment to the 3' splice site of these introns. Furthermore, by using suboptimal doses of THZ531 and PdB, we describe a synergic effect of these inhibitors on intron retention, cell cycle progression and cancer cell survival. These findings uncover a mechanism by which CDK12/13 couple RNA transcription and processing, and suggest that combined inhibition of these kinases and the spliceosome represents an exploitable anticancer approach.
| S-EPMC10287901 | biostudies-literature
Project description:UNLABELLED:Uveal melanoma, the most common eye malignancy, causes severe visual morbidity and is fatal in approximately 50% of patients. Primary uveal melanoma can be cured by surgery or radiotherapy, but the metastatic disease is treatment refractory. To understand comprehensively uveal melanoma genetics, we conducted single-nucleotide polymorphism arrays and whole-genome sequencing on 12 primary uveal melanomas. We observed only approximately 2,000 predicted somatic single-nucleotide variants per tumor and low levels of aneuploidy. We did not observe an ultraviolet radiation DNA damage signature, but identified SF3B1 mutations in three samples and a further 15 mutations in an extension cohort of 105 samples. SF3B1 mutations were associated with good prognosis and were rarely coincident with BAP1 mutations. SF3B1 encodes a component of the spliceosome, and RNA sequencing revealed that SF3B1 mutations were associated with differential alternative splicing of protein coding genes, including ABCC5 and UQCC, and of the long noncoding RNA CRNDE. SIGNIFICANCE:Our data show that despite its dismal prognosis, uveal melanoma is a relatively simple genetic disease characterized by recurrent chromosomal losses and gains and a low mutational burden. We show that SF3B1 is recurrently mutated in uveal melanoma, and the mutations are associated with aberrant alternative splicing.
| S-EPMC5321577 | biostudies-literature