cDNA cloning and chromosomal mapping of a novel human GAP (GAP1M), a GTPase-activating protein of Ras.
We have previously isolated a novel Ras GTPase-activating protein (Ras GAP), Gap1m, from rat brain. Gap1m is considered to be a negative regulator of the Ras signaling pathways, like other Ras GAPs, neurofibromin, which is a gene product of the neurofibromatosis type I gene, and p120GAP. In this study we have isolated a human cDNA of this Gap and mapped the gene. The gene encodes a protein of 853 amino acids that shows 89% sequence identity to rat Gap1m. The human gene was mapped to chromosome 3 by PCR analysis on a panel of human-mouse hybrid cells. FISH analysis refined the location of the gene further to 3q22-q23.