Further observations on the inducibility of the 93D puff of Drosophila melanogaster by homogenate of heat shocked cells

Abstract

The 93D-inducing activity of the homogenate of heat shocked D. melanogaster larvae remains unaffected even if the homogenate is heated to 80°C (30 min) or to 80°C (10 min). In contrast, a homogenate of heat shocked D. hydei larvae loses its 2-48C (a 93D-like puff) inducing activity if heated to 80° or 100° C. Thus it appears that the 93D-inducing factor is different and perhaps is non-proteinaceous in nature. Cytoplasmic fraction of heat shocked brain cells of D. melanogaster larvae has been found to have 93-D-inducing activity.