hNRAGE, a human neurotrophin receptor interacting MAGE homologue, regulates p53 transcriptional activity and inhibits cell proliferation

hNRAGE, a neurotrophin receptor p75 interacting MAGE homologue, is cloned from a human placenta cDNA library. hNRAGE can inhibit the colony formation of and arrest cell proliferation at the G1/S and G2/M stages in hNRAGE overexpressing cells. Interestingly, hNRAGE also increases the p53 protein level as well as its phosphorylation (Ser392). Further studies demonstrated that hNRAGE does not affect the proliferation of mouse p53−/− embryonic fibroblasts, suggesting that p53 function is required for hNRAGE induced cell cycle arrest. Moreover, the cell cycle inhibiting protein p21WAF is induced by hNRAGE in a p53 dependent manner. The data provide original evidence that hNRAGE arrests cell growth through a p53 dependent pathway.