| Modification Notes |
SRp75, also designated splicing factor, arginine/serine-rich 4 (SFRS4), is a splicing factor that can undergo phosphorylation. SRp75 is similar to other SR proteins, containing an N-terminal RNA recognition motif (RRM), a glycine-rich region, an internal region homologous to the RRM and a long 315 amino acid C-terminal serine/arginine-rich domain. SRp75, Pnn, SRm300 and SRrp130 components of spliceosome machinery can co-localize and co-immunoprecipitate with one another and exhibit speckled nuclear distribution that aligns with components of pre-mRNA splicing machinery. Alternative mRNA splicing plays an important role in development and differentiation; many transcripts are spliced differently in distinct cell types and tissues. Both constitutive and alternative splicing occurs on spliceosomes, which are complex particles composed of small nuclear ribonucleoproteins (snRNPs) and non-snRNP proteins. The SR family of non-snRNP splicing factors contain an RNA recognition motif and a serine- and arginine-rich (SR) domain. SR proteins are required at early stages of spliceosome assembly, have distinct but overlapping specificities for different pre-mRNAs and can alter splice site choice. |
