L. Nover and L. Hightower Though the roots of experimental stress biology at the cellular and organismic level can be traced back to the middle of the last century (Nover 1989), a decisive breakthrough came only in 1962 with the report on stress-induced changes of gene activity in Drosophila (Ritossa 1962) and the subsequent identification of the newly synthesized heat stress proteins (Tissieres et al. 1974) and mRNAs, respectively (McKenzie et al1975; McKenzie and Meselson 1977). The selectivity of induction and the high rate of accumulation of Hsps facilitated the cloning and sequencing of the hs genes in Drosophila and the demonstration that all organisms react similarly when exposed to heat stress or chemical stressors (Ashbumer and Bonner 1979; Schlesinger et al. 1982; Nover 1984). The explosive development of molecular stress research in the following 10 years illustrated that the stress response represents a characteristic network of dramatic but transient changes at many levels of cellular structure and function, including gene expression (Atkinson and Walden 1985; Tomasovic 1989; Georgopoulos et al. 1990; Nover et al. 1990; Nover 1991). Besides the characterization of the hs genes and the mechanism of their induction, major interest concentrated on the heat stress proteins and their possible roles in induced stress tolerance. Rapidly, it became apparent that the major stress proteins are coded by five conserved multigene families (Lindquist and Craig 1988: Nover et al.

I Heat Shock-Induced Developmental Abnormalties

1 Heat Shock Effects in Snail Development
2 Environmentally Induced Development Defects in Drosophila
3 The Use of Heat-Shock-Induced Ectopic Expression to Examine the Functions of Genes Regulating Development
4 Thermotolerance and Heat Shock Response During Early Development of the Mammalian Embryo
5 Strain Differences in Expression of the Murine Heat Shock Response: Implications for Abnormal Neural Development
II Cell-Specific and Developmental Control of Hsp Synthesis
6 The Expression of Heat Shock Protein and Cognate Genes During Plant Development
7 Expression of Heat Shock Proteins During Development in Drosophila
8 Regulation of Heat Shock Gene Expression During Xenopus Development
9 Heat Shock Gene Expression During Mammalian Gametogenesis and Early Embryogenesis
10 Heat Shock Protein Synthesis in Preimplantation Mouse Embryo and Embryonal Carcinoma Cells
11 Transcriptional Regulation of Human Hsp70 Genes: Relationship Between Cell Growth, Differentiation, Virus Infection, and the Stress Response
12 Transforming Growth Factor-? Regulates Basal Expression of the hsp70 Gene Family in Cultured Chicken Embryo Cells
13 Cell Growth, Cytoskeleton, and Heat Shock Proteins
14 Expression of Heat Shock Genes (hsp70) in the Mammalian Nervous System.