DIMERIZATION & COOPERATIVITY IN PROKARYOTIC GENE CONTROL

二聚化

• 批准号: 6180699
• 负责人: Ann Hochschild
• 金额: $ 30.79万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-09-01 至 2003-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6180699
• 关键词: Escherichia coli; bacterial genetics; cAMP response element binding protein; genetic techniques; protein protein interaction; technology /technique development; transcription factor

The control of transcription depends on DNA-bound regulatory proteins and their interactions. The proposed research is aimed at examining two important classes of protein-protein interactions, dimerization and cooperativity, using several prokaryotic model systems. Genetic methods will be employed to identify the molecular determinants that govern the specificity of these interactions. Many transcriptional regulators in both prokaryotes and eukaryotes function in dimeric form, either as homodimers or heterodimers, and in some cases the same protein can associate with alternative partners, carrying out distinct regulatory functions depending on its partner. Thus, the proper biological activity depends on the abilities of potential partners to discriminate amongst one another so that only the correct dimeric species are formed. The proposed research will address the problem of dimerization specificity with an analysis of the dimerization specified of the E. coli cAMP receptor protein (CRP) and its homologue FNR. Many transcriptional regulators also bind cooperatively to the DNA in either homotypic or heterotypic combinations. The assembly of eukaryotic regulatory complexes, in particular, typically involves multiple DNA- bound proteins that participate in a variety of weak protein-protein interactions. Cooperativity is both a mechanism for generating sensitive biological switches by providing a steep dose-response cure, as well as a means by which multiple regulatory inputs can be integrated. The proposed research will probe the nature of the underlying protein- protein interactions with a detailed analysis of model cooperativity interface, that of the bacteriophage lambda repressor and its homologues. A general objective of the proposed research is the development of new genetic methods that can be widely applied to the study of biologically important protein-protein interactions. A recently developed E. coli- based two-hybrid assay will be tested for its efficacy in detecting interacting proteins encoded in complex libraries. This assay will also be applied to the study and manipulation of a phosphorylation-dependent protein-protein interaction involving the eukaryotic transcription factor CREB and its CREB and its co-activator CBP.

转录的控制依赖于DNA结合的调节蛋白及其相互作用。拟议的研究的目的是研究两个重要类的蛋白质-蛋白质相互作用，二聚化和协同性，使用几个原核模型系统。遗传学方法将被用来确定控制这些相互作用特异性的分子决定因素。原核生物和真核生物中的许多转录调节因子以二聚体形式起作用，作为同源二聚体或异源二聚体，并且在某些情况下，相同的蛋白质可以与替代伴侣缔合，根据其伴侣执行不同的调节功能。因此，适当的生物学活性取决于潜在伴侣彼此区分的能力，从而仅形成正确的二聚体种类。本研究将通过对大肠杆菌特异性二聚化的分析来解决二聚化特异性的问题。coli cAMP受体蛋白（CRP）及其同源物FNR。许多转录调节因子也以同型或异型组合的方式协同结合DNA。特别地，真核调节复合物的组装通常涉及参与多种弱蛋白质-蛋白质相互作用的多个DNA结合蛋白质。协同性既是一种通过提供陡峭的剂量反应治愈来产生敏感的生物开关的机制，也是一种可以整合多个调节输入的手段。拟议的研究将探索潜在的蛋白质-蛋白质相互作用的性质，详细分析模型协同界面，即噬菌体λ阻遏物及其同系物。拟议研究的总体目标是开发新的遗传方法，可广泛应用于生物学上重要的蛋白质-蛋白质相互作用的研究。最近开发的E.将测试基于大肠杆菌的双杂交测定在检测复杂文库中编码的相互作用蛋白质中的效力。该测定也将应用于涉及真核转录因子CREB及其CREB和其共激活因子CBP的磷酸化依赖性蛋白质-蛋白质相互作用的研究和操作。