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AKAP95 regulates splicing through scaffolding RNAs and RNA processing factors

ABSTRACT: Alternative splicing of pre-mRNAs significantly contributes to the complexity of gene expression in higher organisms, but the regulation of the splice site selection remains incompletely understood. We have previously demonstrated that a chromatin-associated protein, AKAP95 (AKAP8), has a remarkable activity in enhancing chromatin transcription. In this study, we have shown that AKAP95 physically interacts with many factors involved in transcription and RNA processing, and functionally regulates pre-mRNA splicing. AKAP95 directly promotes splicing in vitro and the inclusion of a specific exon of an endogenous gene FAM126A. The N-terminal YG-rich domain of AKAP95 is important for its binding to RNA processing factors including selective groups of hnRNP proteins, and its zinc finger domains are critical for pre-mRNA binding. Genome-wide binding assays revealed that AKAP95 bound preferentially to proximal intronic regions on a large number of pre-mRNAs in human transcriptome, and AKAP95 depletion predominantly resulted in reduced inclusion of many exons. AKAP95 also selectively coordinates with hnRNP H/F and U proteins in regulating alternative splicing events. We have further shown that AKAP95 directly interacts with itself. Taken together, our results establish AKAP95 as a novel and mostly positive regulator of pre-mRNA splicing and a possible integrator of transcription and splicing regulation, and support a model that AKAP95 regulates pre-mRNA splicing via through scaffolding RNAs and RNA processing factors and facilitating the splice site communication.

OTHER RELATED OMICS DATASETS IN: PRJNA323422

ORGANISM(S): Mus musculus Homo sapiens

PROVIDER: GSE81916 | GEO | 2016/09/08

SECONDARY ACCESSION(S): PRJNA323422

REPOSITORIES: GEO

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