Sequence-specific RNA-binding protein which participates in the control of pre-mRNA splicing. Binds to A3 enhancer proteins SRp75, SRp55, SRp40 and SRp30 (Probable). Interacts with ILDR1 (via C-terminus) and ILDR2 (By similarity). Phosphorylated in the RS domains. Belongs to the splicing factor SR family.