Testis Specific Y Encoded Like Protein 2 (TSPYL2)

CDA1 was phosphorylated by CDK4 , CDK2, and CDK1 (CDC2) in vitro, and mutation analysis showed that CDA1 was phosphorylated on ser20 and thr340 by CDK2 in HeLa cells. CDA1 levels were low in serum-starved HeLa cells and increased dramatically with serum stimulation. Expression of full-length CDA1, but not its N terminus, arrested HeLa cell growth, colony number, cell density, and bromodeoxyuridine uptake in a dose-dependent manner.

The ability of CDA1 to arrest cell growth was abolished by mutation of the 2 CDK consensus phosphorylation sites. CDA1 is a negative regulator of cell growth whose activity is regulated by its expression level and phosphorylation.