Serine/arginine-rich splicing factor 1 （SFRS1） belongs to the arginine/serine-rich splicing factor protein family， and functions in both constitutive and alternative pre-mRNA splicing. SFRS1 binds to pre-mRNA transcripts and components of the spliceosome， and can either initiate or inhibit splicing depending on the position of the pre-mRNA binding site. The ability of SFRS1 to activate splicing is controlled by phosphorylation and interactions with other splicing factor associated proteins.
