SH2 Domain Binding Protein 1 (SH2BP1)

CTR9, parafibromin (CDC73), LEO1, and PAF1 form the PAF protein complex, which associates with the RNA polymerase II subunit POLR2A and with a histone methyltransferase complex.The N-terminal two-thirds of the deduced 1,173-amino acid protein contains 15 tetratricopeptide repeats (TPRs), and the C-terminal third contains a serine- and glutamic acid-rich SH2-binding domain. Mouse and human SH2BP1 share 98.6% amino acid identity. Northern blot analysis detected expression in all mouse tissues examined. Western blot analysis of a human B-cell lymphoma cell line detected endogenous SH2BP1 at an apparent molecular mass of 150 kD. Immunolocalization of Sh2bp1 in mouse fibroblasts revealed a speckled nuclear staining pattern.