THE DROSOPHILA-MELANOGASTER HOMOLOG OF THE HSP60 GENE IS ENCODED BY THE ESSENTIAL LOCUS L(1)10AC AND IS DIFFERENTIALLY EXPRESSED DURING FLYDEVELOPMENT

The hsp60 (heat-shock protein 60) gene family of molecular chaperones has been a subject of study in numerous systems due to its important r ole in the correct folding of non-native proteins in development as we ll as after heat-shock treatment. Here we present the characterization of the first Drosophila hsp60 homologue. Drosophila HSP60 is most clo sely related (72% identity across the entire protein sequence) to the mouse mitochondrial HSP60. Western blot experiments indicate that Dros ophila HSP60 is enriched in the mitochondrial fraction. The distributi on of HSP60 protein is dynamic during fly embryogenesis, suggesting th at various cell types might have different HSP60 requirements. The mol ecular analysis of a P-element-induced mutation that affects the l(1)1 0Ac locus shows that the transposon is inserted in a 3-kb intron prese nt in the hsp60 gene. By genetic rescue experiments we prove that Dros ophila HSP60 is encoded by the essential locus l(1)10Ac opening the po ssibility for detailed genetic analysis of HSP60 functions in the fly.