Y-Box Binding Protein 2 (YBX2)

YBX2 is a germ-cell specific member of the vertebrate Y box family of nucleic acid-binding proteins . The deduced 364-amino acid protein has a calculated molecular mass of 38.6 kD and is arginine- and proline-rich. It shares 69% and 73% amino acid identity with DBPA (CSDA) and YB1 (NSEP1), respectively, and contains an N-terminal cold-shock domain (CSD), 7 putative phosphorylation sites for casein kinase II, 3 potential phosphorylation sites for protein kinase C, and 2 nuclear localization signals within a B/A island. Northern blot analysis detected a 1.8-kb transcript in human testes only. YBX2 shares 93% and 77% amino acid identity with mouse Ybx2 and Xenopus Frgy2, respectively.The deduced 360-amino acid mouse Msy2 and 282-amino acid Msy2a isoforms have calculated molecular masses of 38 and 31 kD, respectively.