MECHANISM OF REGULATION OF HEAT SHOCK GENE EXPRESSION

胚胎发育、细胞分化或 对新环境的适应， 各种基因的表达。 我们对这些的理解 因此，过程的关键取决于我们对以下方面的了解： 基因调控的分子机制。 热休克蛋白 (hsp)基因将被用作研究的模型系统， 分子水平，基因调控方面，在上述几个 流程. 这些基因通常以非常低的水平表达 但在高温下被激活， 细胞压力，它们的产物被认为可以保护细胞 抵抗压力损伤 这些基因中的一些也在 正常发展的不同阶段。 果蝇和其他hsp基因出现热诱导表达 依赖于启动子中调节单元的存在 由（最少）两个HSP基因特异性结合位点组成 转录因子 这一因素持续存在 在细胞中，被压力激活，然后与调节结合， 单位 早期的发现表明， 与调控单元相互作用产生启动子 活动 我们建议（1）继续进行体内和体外研究 来定义因子分子之间的相互作用 结合热休克单位，（2）提高抗体， 这种因子，并获得其cDNA基因，以确定性质， 因子分子间的相互作用及其机制 因子活化，（3）纯化和表征另一因子 可能参与了 果蝇hsp23基因（蜕皮甾酮受体），和（4）至 表征热休克蛋白23的第二种类型的发育调节 基因

Processes such as embryonic development, cell differentiation or adaptation to new environments all involve changes in the levels of expression of various genes. Our understanding of these processes is, therefore, critically dependent on our knowledge of the molecular mechanisms of gene regulation. Heat shock protein (hsp) genes will be used as a model system for studying, at the molecular level, aspects of gene regulation in several of the above processes. These genes are typically expressed at very low levels but are activated at elevated temperatures and by a number of cellular stresses, and their products are thought to protect cells against stress damage. Some of these genes are also active at different stages of normal development. Heat-induced expression of Drosophila and other hsp genes appears to depend on the presence in the promoters of a regulation unit consisting (minimally) of two binding sites for a hsp gene-specific transcription factor. This factor, which is continuously present in cells, is activated by stress and then binds to the regulation unit. Earlier findings suggest that the factor molecules binding to the regulation unit need to interact to produce promoter activity. We propose (1) to continue in vivo and in vitro studies to define the relevant interactions between factor molecules binding to the heat shock unit, (2) to raise antibodies against such a factor and to obtain its cDNA gene to define the nature of the interactions between factor molecules and the mechanism of factor activation, (3) to purify and characterize another factor likely to be involved in the developmental regulation of the Drosophila hsp23 gene (ecdysterone receptor), and (4) to characterize a second type of developmental regulation of the hsp23 gene.