Srsf10 and the minor spliceosome control tissue-specific and dynamic SR protein expression.

Stefan Meinke,Florian Heyd,Gesine Goldammer,A Ioana Weber,Alexander Neumann,Marco Preussner,Victor Tarabykin

doi:10.7554/elife.56075

Stefan Meinke, Florian Heyd + Show 5 more

Open Access

https://doi.org/10.7554/elife.56075

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Abstract

Minor and major spliceosomes control splicing of distinct intron types and are thought to act largely independent of one another. SR proteins are essential splicing regulators mostly connected to the major spliceosome. Here, we show that Srsf10 expression is controlled through an autoregulated minor intron, tightly correlating Srsf10 with minor spliceosome abundance across different tissues and differentiation stages in mammals. Surprisingly, all other SR proteins also correlate with the minor spliceosome and Srsf10, and abolishing Srsf10 autoregulation by Crispr/Cas9-mediated deletion of the autoregulatory exon induces expression of all SR proteins in a human cell line. Our data thus reveal extensive crosstalk and a global impact of the minor spliceosome on major intron splicing.

Highlights

Alternative splicing (AS) is a major mechanism that controls gene expression (GE) and expands the proteome diversity generated from a limited number of primary transcripts (Nilsen and Graveley, 2010)
We show that Srsf10 recognizes a highly conserved splicing enhancer element within its own pre-mRNA, which results in the production of a non-protein coding mRNA isoform and thereby the regulation of its own expression level
The upstream minor splice site is coupled to E4 inclusion and production of a protein coding mRNA, while use of the downstream major splice site is coupled to exon 3 (E3) inclusion, the presence of a premature translation termination codons (PTC) and the use of an alternative polyadenylation site in E3 (Figure 1A)

Summary

Introduction

Alternative splicing (AS) is a major mechanism that controls gene expression (GE) and expands the proteome diversity generated from a limited number of primary transcripts (Nilsen and Graveley, 2010). We found that the expression levels of most other SR proteins correlate with Srsf expression This is directly mediated through the levels of Srsf and the competition between major and minor splice sites, as CRISPR/Cas9-mediated removal of the autoregulatory exon 3 of Srsf increases the expression of Srsf, and the expression of the other SR proteins. These data connect the minor spliceosome with Srsf and SR protein expression in a tissue- and differentiation state-specific manner. We reveal a mechanism that coordinately controls SR protein expression in different cellular conditions and that connects the minor spliceosome with global (alternative) splicing of major introns

Results and discussion

AC AC AC

Materials and methods

A Ioana Weber A Ioana Weber Marco Preussner