IDENTIFICATION AND CHROMOSOMAL ASSIGNMENT OF USP1, A NOVEL GENE ENCODING A HUMAN UBIQUITIN-SPECIFIC PROTEASE

We have cloned a novel gene encoding a human ubiquitin-specific protea se (USP1). The product, which consists of 785 amino acids with a deduc ed molecular mass of 88.2 kDa, possesses His and Cys domains that are highly conserved in all members of the ubiquitin-specific processing ( UBP) family of proteases, Recombinant USP1 protein showed genuine UBP activity, correctly cleaving Ub-beta-galactosidase to produce ubiquiti n and P-galactosidase. Chromosomal mapping by fluorescence in situ hyb ridization and radiation hybrid analyses localized the USP1 gene to th e p31.3-p32.1 band of chromosome 1. As losses of heterozygosity or amp lifications have been observed in the distal region of the short arm o f chromosome 1 in some neuroblastomas, breast cancers, and pancreatic adenocarcinomas, the USP1 gene may be a candidate for either the tumor -suppressive or the oncogenic activities associated with that chromoso mal region. (C) 1998 Academic Press.