The regulation and function of small heat‐shock protein synthesis

The four small heat shock protein genes of Drosophila are tightly linked at the level of DNA, and are coordinately regulated. In cultured cell lines their expression is induced by high temprature shock and by physiological doses of ecdysterone. In vivo , small heat shock gene expression is developmentally regulated. Using recombinant DNA clones we have characterized and compared small hsp gene induction in response to the two independent stimuli.