Chen Hao, Tang Hong, Ebright Richard H
Waksman Institute, Department of Chemistry, Rutgers University, Piscataway, NJ 08854, USA.
Mol Cell. 2003 Jun;11(6):1621-33. doi: 10.1016/s1097-2765(03)00201-6.
We show that the Escherichia coli RNA polymerase (RNAP) alpha subunit C-terminal domain (alphaCTD) functionally interacts with sigma(70) at a subset of UP-element- and activator-dependent promoters, we define the determinants of alphaCTD and sigma(70) required for the interaction, and we present a structural model for the interaction. The alphaCTD-sigma(70) interaction spans the upstream promoter and core promoter, thereby linking recognition of UP-elements and activators in the upstream promoter with recognition of the -35 element in the core promoter. We propose that the alphaCTD-sigma(70) interaction permits UP-elements and activators not only to "recruit" RNAP through direct interaction with alphaCTD, but also to "remodel" RNAP-core-promoter interaction through indirect, alphaCTD-bridged interactions with sigma(70).
我们发现，大肠杆菌RNA聚合酶（RNAP）的α亚基C末端结构域（αCTD）在一部分依赖上游元件（UP元件）和激活因子的启动子上与σ70发生功能相互作用。我们确定了相互作用所需的αCTD和σ70的决定因素，并提出了相互作用的结构模型。αCTD与σ70的相互作用跨越上游启动子和核心启动子，从而将上游启动子中UP元件和激活因子的识别与核心启动子中-35元件的识别联系起来。我们提出，αCTD与σ70的相互作用使UP元件和激活因子不仅能够通过与αCTD的直接相互作用“招募”RNAP，还能通过与σ70的间接αCTD桥接相互作用“重塑”RNAP与核心启动子的相互作用。
