RNA-binding protein that plays a role in the regulation of alternative splicing and influences mRNA splice site selection and exon inclusion. Its phosphorylation by FYN inhibits its ability to regulate splice site selection. Induces an increased concentration-dependent incorporation of exon in CD44 pre-mRNA by direct binding to purine-rich exonic enhancer. May function as an adapter protein for Src kinases during mitosis (By similarity). Binds both poly(A) and poly(U) homopolymers (By similarity). Phosphorylation by PTK6 inhibits its RNA-binding ability (By similarity). Self-associates to form homooligomers. Interacts with SAFB, SFRS9 and YTHDC1. Found in a complex with KHDRBS1, KHDRBS2 and KHDRBS3. Interacts with RBMX (By similarity). Interacts with the SH3 domains of FYN and PLCG1 (By similarity). Interacts with the SH2 domains of FYN, GRAP2, PLCG1 and RASA1 (By similarity). Interacts with RBMX. Expressed in the cortex, cerebellum, striatum, midbrain, brainstem and thalamus of the brain (at protein level). Expressed in neurons (at protein level). Expressed in brain and testis. Expressed in the dentate gyrus of the hippocampus. Methylated. Phosphorylated on tyrosine residues by FYN. Tyrosine phosphorylated by PTK6 and SRC (By similarity). Tyrosine phosphorylated by SRC during mitosis (By similarity). Belongs to the KHDRBS family.