Regulation of Pre-mRNA Splicing: Indispensable Role of Post-Translational Modifications of Splicing Factors.

Pre-mRNA splicing is a process used by eukaryotic cells to generate messenger RNAs that can be translated into proteins. During splicing, the non-coding regions of the RNAs (introns) are removed from pre-mRNAs and the coding regions (exons) are joined together, resulting in mature mRNAs. The particular steps of splicing are executed by the multimegadalton complex called a spliceosome. This complex is composed of small nuclear ribonucleoproteins, various splicing factors, and other regulatory and auxiliary proteins. In recent years, various post-translational modifications of splicing factors have been shown to contribute significantly to regulation of processes involved in pre-mRNA splicing. In this review, we provide an overview of the most important post-translational modifications of splicing factors that are indispensable for their normal function during pre-mRNA splicing (i.e., phosphorylation, acetylation, methylation, ubiquitination and sumoylation). Moreover, we also discuss how the defects in regulation of splicing factors are related to the development of cancer.