Characterization, chromosomal assignment, and tissue expression of a novelhuman gene belonging to the ARF GAP family

We have identified and characterized a novel human ADP-ribosylation factor GTPase-activating protein (ARFGAP1) gene that is related to other members o f the ARF GAP family. The full-length cDNA for human ARFGAP1 was cloned fol lowing the identification of an EST obtained by large-scale cDNA library se quencing through a Blast search of public databases. Structurally, ARFGAP1 encodes a polypeptide of 516 amino acids, which contained a typical GATA-1- type zinc finger motif (CXXCX16CXXC) with the four cysteine residues that a re highly conserved among other members of the ARF GAP family. The conserve d ARF GAP domain may emphasize the biological importance of this gene. The ARFGAP1 gene, which contained 16 exons ranging from 0.5 to 9.3 kb, was mapp ed to human chromosome 22q13.2-q13.3 using radiation hybridization and in s ilico analyses. ARFGAP1 is strongly expressed in endocrine glands and testi s. Interestingly, the expression of ARFGAP1 in testis is about sixfold high er than that in ovary, indicating a possible role of ARFGAP1 in the physiol ogical function of sperm. Expression of ARFGAP1 in four human fetal tissues and seven cancer cell lines was also detected. (C) 2000 Academic Press.