Transducer Of ERBB2, 2 (TOB2)

TOB2 belongs to the TOB/BTG1 family of antiproliferative proteins, which are involved in the regulation of cell cycle progression.The deduced 344-amino acid TOB2 polypeptide has a calculated molecular mass of 37 kD. It shares 61% overall sequence homology with the TOB1 protein, and both proteins contain a putative nuclear localization signal in the conserved N-terminal domain. Immunofluorescence analysis revealed localization almost exclusively in the cytoplasm. Northern blot analysis of human adult tissues detected ubiquitous expression of a 4.1-kb transcript, with relatively high expression in skeletal muscle, thymus, and ovary. In situ hybridization in several mouse tissues demonstrated intense hybridization in ovary, with characteristic expression in oocytes. Immunoblot analysis revealed a 43-kD protein.