HUMAN CAAF1 GENE - MOLECULAR-CLONING, GENE STRUCTURE, AND CHROMOSOME MAPPING

We have isolated and characterized a cDNA and the gene of the human ho mologue of CAAF1, a novel member of the S100 calcium-binding protein f amily. The 276-bp open reading frame encoded a 92-amino acid polypepti de with a predicted molecular mass of 10,575 Da. The deduced amino aci d sequence of human CAAF1 showed 66% homology to bovine CAAF1. The hum an CAAF1 gene consisted of three exons, with the two EF hand motifs of the CAAF1 protein separately encoded by exons 2 and 3. This gene was expressed at a high level in polymorphonuclear leukocytes and at an in termediate level in esophageal mucosa. The tissue distribution of CAAF 1 mRNA was different from that of other S100 proteins. Direct R-bandin g fluorescence in situ hybridization revealed that the human CAAF1 gen e was mapped to chromosome 1q21.2-q22, where most of the S100 genes fo rm a cluster. (C) 1996 Academic Press Inc.