In the present study, a new member of melanoma associated antigens (Mage), named Restin (219 amino acids), was identified from HL-60 cell induced by all-frans-retinoic acid (ATRA) by PCR-based subtractive hybridization. Bioinformatics analysis found this novel gene shares high homolog with Necdin (a neuronal growth suppressor, 49%). Both of them are basic proteins. Moreover, the Restin, Necdin and Mages are in one protein superfamily. This fact indicates that the Restin and Mages are mutually related but functionally different. Further analysis found that they can be divided into two subgroups, the acid and the basic. Restin, Necdin and Mage-D1 have an alkaline conserve region (PI is from 8.6 to 10.1), which are not or less expressed in tumor tissues but mostly in normal tissues. It has been reported that Necdin can arrest the cell proliferation by interaction with p53 and E2F1. Therefore, all of them are probably related to arrest the cell cycle. However, the Mage A and C are primarily acid proteins (PI In the present study, a new member of melanoma associated antigens (Mage), named Restin (219 amino acids), was identified from HL-60 cell induced by all-frans-retinoic acid (ATRA) by PCR-based subtractive hybridization. Bioinformatics analysis of this novel gene shares high homolog with Necdin (a neuronal growth suppressor, 49%). Both, the Restin, Necdin and Mages are in one protein superfamily. This fact indicates that the Restin and Mages are mutually related but but functionally different. Further analysis found that they can be divided into two subgroups, the acid and the basic. Restin, Necdin and Mage-D1 have an alkaline conserve region (PI is from 8.6 to 10.1), which are not or less It has been reported that Necdin can arrest the cell proliferation by interaction with p53 and E2F1. However, the all of them are likely related to arrest the cell cycle. However, the Mage A and C are primaril y acid proteins (PI