Project description:The mRNA transcriptome profiling and splicing profiling mediated by LOC90024 and LOC90024-encoded small protein SRSP were investigated by RNA-seq.
Project description:The mRNA transcriptome profiling and splicing profiling mediated by LINC00266-1 and LINC00266-1-encoded peptide were investigated by RNA-seq.
Project description:RRP1B is a Metastasis Modifier that Regulates the Transcriptome through mRNA Splicing To assess the role of RRP1B in alternative mRNA splicing, we knocked down the expression of Rrp1b in the highly metastatic mouse mammary tumor cell line Mvt-1 using shRNA. Two control and two knockdown stable cell lines were selected for RNA-sequencing.
Project description:The high-risk subgroup of Human papilloma viruses (HPVs), exemplified by HPV16/18, are causally linked to human cancers of the anogenital tract, skin, and upper aerodigestive tract. The high-risk HPV oncoproteins E6 and E7 are expressed from a polycistronic transcript that can potentially give rise to alternatively spliced E6 mRNAs, a process important for E6 and E7 expression and oncogenic transformation. Previously, we identified ECD, the human homologue of the Drosophila ecdysoneless gene, as a novel HPV16 E6-interacting protein using Yeast two-hybrid system. Here, we show that the C-terminal region of ECD selectively binds to high-risk but not to low-risk HPV E6 proteins. We demonstrate that ECD is overexpressed in HPV+ as well as HPV- cervical and head and neck patient tumor samples. Using the TCGA dataset, we show that ECD mRNA overexpression predicts shorter survival in these cancer patients. Recent work from our laboratory showed that ECD associates with several components of RNA biogenesis/splicing machinery and are involved in mRNA export. Here, we show that ECD is an RNA binding protein and regulates mRNA splicing. RNAseq analyses of SiHa cells upon ECD knockdown (KD) revealed alterations of many cellular pathways with prominent downregulation of components of the mRNA splicing machinery. Further investigation revealed that ECD KD resulted in dysregulation of E6 RNA splicing, resulting in decreased E7 and increased RB protein. Furthermore, ECD KD dysregulated several cellular mRNAs known to be critical for HPV oncogenesis. Finally, we demonstrate that while ECD KD in cervical cancer cell lines led to a reduction in oncogenic traits, ECD overexpression together with E7 led to the immortalization of keratinocytes. Taken together, our results support a novel role of ECD in transcription and in viral and cellular mRNA splicing to support HPV-driven oncogenesis.
Project description:RNA splicing, the process of intron removal from pre-mRNA, is essential for the regulation of gene expression. It is controlled by the spliceosome, a megadalton RNA-protein complex that assembles de novo on each pre-mRNA intron via an ordered assembly of intermediate complexes. Spliceosome activation is a major control step requiring dramatic protein and RNA rearrangements leading to a catalytically active complex. Splicing factor 3B subunit 1 (SF3B1) protein, a subunit of the U2 snRNP, is phosphorylated during spliceosome activation, but the responsible kinase has not been identified. Here we show that cyclin-dependent kinase 11 (CDK11) associates with SF3B1 and phosphorylates threonine residues at its N-terminus during spliceosome activation. The phosphorylation is important for association of SF3B1 with U5 and U6 snRNAs in spliceosome activated Bact complex and it can be blocked by OTS964, a potent and selective inhibitor of CDK11. CDK11 inhibition prevents spliceosomal transition from the precatalytic complex B to the activated complex Bact and leads to widespread intron retention and accumulation of non-functional spliceosomes on pre-mRNAs and chromatin. We characterize OTS964 as a quality chemical biology probe for CDK11 and demonstrate a central role of CDK11 in spliceosome assembly and splicing regulation.