Developmental regulation of the heat-shock response.

Abstract

Cell differentiation in the development of multicellular organisms occurs as a consequence of the generation of chronologically and spatially distinct patterns of protein synthesis. These unique constellations of proteins confer on cells the functional and structural characteristics that enable them to perform their specialized roles in the organism. However, in addition to the overt protein synthetic profile, cells may retain the potential to produce proteins that they would not normally produce in significant amounts. During periods of stress, this potential is realized and is evidenced by the synthesis of a set of stress proteins. As discussed in this chapter, the pattern of stress protein synthesis is also subject to developmental regulation. Thus, cells are simultaneously engaged in two parallel developmental processes: regulation of the patterns of overt and stress-inducible protein synthesis. Stress-inducible protein synthesis can be evoked by regulation at either the transcriptional or translational levels, or both. Thus, regulation at both levels must be subject to developmental modulation.