Centrosomal Protein 57kDa (CEP57)

Translokin binds basic fibroblast growth factor (FGF2) and mediates its nuclear translocation and mitogenic activity. The deduced 474-amino acid protein contains transmembrane domains and shares about 17% identity with smooth muscle myosin (MYH11). The deduced 500-amino acid protein shares about 88% sequence identity with the mouse and bovine homologs. Other transcripts of about 2.6 and 2.2 kb were expressed at highest levels in heart and skeletal muscle, with lowest levels in lung. RT-PCR and Western blot analysis detected expression in all cell lines examined. The translokin protein showed an apparent molecular mass of about 55 kD. Epitope-tagged translokin localized to the cytoplasm of transfected COS-7 cells in a distribution that completely overlapped with microtubules.