CRYOEM OF BACTERIAL TRANSCRIPTION ACTIVATION COMPLEXES

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 分解代谢物激活蛋白（CAP;也称为cAMP受体蛋白，CRP）在大肠杆菌中激活一百多个启动子的转录。 CAP是一种分子量为45 kDa的同源二聚体，它与靶启动子内或附近的特异性DNA位点结合，增强了450 kDa E. coli RNA聚合酶全酶（RNAP）结合并启动转录。 简单的CAP依赖性启动子-即仅需要CAP进行转录激活的启动子-可以基于CAP的DNA位点的位置和相应的转录激活机制分为两类。为了完成我们的理解CAP如何完成转录激活，完整的结构模型CAP-holoRNAP-DNA启动子复合物是必需的。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The catabolite activator protein (CAP; also known as the cAMP receptor protein, CRP) activates transcription at more than one hundred promoters in Escherichia coli. CAP, a 45 kDa homodimer, binds to specific DNA sites in or near target promoters and enhances the ability of the 450 kDa E. coli RNA polymerase holoenzyme (RNAP) to bind and initiate transcription. Simple CAP-dependent promoters--i.e. promoters that require only CAP for transcription activation--can be grouped into two classes based on the position of the DNA site for CAP and the corresponding mechanism for transcription activation. To complete our understanding of how CAP accomplishes transcription activation, full structural models for CAP-holoRNAP-DNA promoter complexes are required.