Abstract

The HSP90 family of heat-shock proteins (encoded by genes for HSP90 alpha and beta) constitutes one of the major groups of proteins that are synthesized at increased rates in response to heat and other forms of stress. We previously isolated two distinct cDNA clones for HSP90 alpha from human peripheral blood lymphocytes and from HeLa cells transfected with the adenovirus E1A gene, respectively. To determine the organization of this complex multigene family in the human genome, we used three complementary approaches: Southern analysis of a panel of human/hamster somatic cell hybrids, molecular cloning of the cosmid HSP90 alpha clones from libraries prepared with DNAs from human lymphoblastoid cells, and in situ hybridization to human chromosomes. We demonstrate here that nucleotide sequences that encode HSP90 alpha map to human chromosomes 1q21.2-q22, 4q35, 11p14.1-p14.2, and 14q32.3. The chromosomal mapping of the loci, HSPCAL1, HSPCAL2, HSPCAL3, HSPCAL4, and the characterization of the respective genes should facilitate clarification of the organization of this gene family and lead to a better understanding of the biological functions of the gene product.