FunctionRNA-binding protein that plays a role in the regulation of alternative splicing and influences mRNA splice site selection and exon inclusion. May play a role as a negative regulator of cell growth. Inhibits cell proliferation. Involved in splice site selection of vascular endothelial growth factor. Induces an increased concentration-dependent incorporation of exon in CD44 pre-mRNA by direct binding to purine-rich exonic enhancer. RNA-binding abilities are down-regulated by tyrosine kinase PTK6. Involved in post-transcriptional regulation of HIV-1 gene expression.
Tissue specificityUbiquitous with higher expression in testis, skeletal muscle and brain. Expressed in the kidney only in podocytes, the glomerular epithelial cells of the kidney. Strongly expressed after meiosis.
Sequence similaritiesBelongs to the KHDRBS family. Contains 1 KH domain.
DomainThe proline-rich site binds the SH3 domain of the p85 subunit of PI3-kinase.
Post-translational modificationsPhosphorylated on tyrosine residues. Isoform 1 C-terminal region is tyrosine-rich, but isoform 2 lacking this C-terminal region is also tyrosine-phosphorylated.
Cellular localizationNucleus. Localized in a compartment adjacent to the nucleolus, but distinct from the peri-nucleolar one.