Splicing factor that in its dephosphorylated form acts as a general repressor of pre-mRNA splicing. Seems to interfere with the U1 snRNP 5'-splice recognition of SNRNP70. Required for splicing repression in M-phase cells and after heat shock. May be involved in regulation of alternative splicing in neurons, with isoform 1 acting as a positive and isoform 3 as a negative regulator.
Belongs to the splicing factor SR family. Contains 1 RRM (RNA recognition motif) domain.
Phosphorylated. Fully dephosphorylated in mitosis and partially dephosphorylated on heat shock. Isoform 3 is phosphorylated on Ser-168.