The major heat-shock protein (hsp70) gene family: related sequences in mouse, Drosophila, and yeast.

Heat shock induces the synthesis of a 70-kdalton protein in Escherichia coli, Drosophila, yeast, and mouse. We show that the genes for this heat-shock protein in mouse, yeast, and Drosophila share extensive sequence homology as determined by heteroduplex formation at different stringencies. We calculate that the heat-shock gene homology is 74% between yeast and Drosophila and 85% between mouse and Drosophila. The organization of the six copies of the Drosophila gene for the 70-kdalton heat-shock protein at two separate loci is summarized and evidence is presented that the yeast and mouse genomes each contain multiple copies of sequences related to the Drosophila gene for the 70-kdalton heat-shock protein. These results demonstrate that not only the sequence but also the repetitive organization of the major heat-shock genes is conserved.