 Pre-MRNA splicing is a process used by eukaryotic cells to generate messenger RNAs that can be translated into proteins. During splicing, introns are removed from pre-MRNAs and exons are joined together, resulting in mature mRNAs. Splicing is carried out by the spliceosome, which is composed of small nuclear ribonucleoproteins, splicing factors, and other regulatory and auxiliary proteins. Recent studies have revealed that post-translational modifications of splicing factors play a critical role in regulating pre-MRNA splicing. These modifications include phosphorylation, acetylation, methylation, ubiquitination, and assimilation. Defects in these modifications can lead to disruption of normal cellular functions and may contribute to the development of cancer.