ROGER KORNBERG PRT TIME

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 这项拟议研究的目标是在原子分辨率下确定RNA聚合酶II及其与核酸和辅助蛋白质因子的络合物的X射线结构。这个问题很有挑战性，因为仅聚合酶就由15个多肽组成，总质量近60万道尔顿，加上辅助因子，多肽的数量和蛋白质质量都翻了一番。这个问题的解决需要生化研究、电子和X射线结晶学的结合。目前已有八种类型的RNA聚合酶II晶体，它们是天然酶的晶体，以及与DNA、与RNA、与DNA和RNA处于转录活性状态、与TFIIB、与TFIIE、与附加聚合酶亚基RPB4和RPB7以及与紧密结合的抑制剂a-Amanitin的共晶体。最近的进展包括低分辨包络和相位到6.5°，以及最近收集的几个新的重原子团与RNA POL II络合。现在预测非常好的快速实现高分辨结构。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The goal of the proposed research is to determine the x-ray structures of RNA polymerase II and of its complexes with nucleic acids and auxiliary protein factors at atomic resolution. The problem is challenging, since the polymerase alone comprises 15 polypeptides with a total mass of nearly 600,000 Dalton, and addition of the auxiliary factors doubles both the number of polypeptides and the protein mass. Solution of the problem requires a combination of biochemical studies, electron and X-ray crystallography. Eight types of RNA polymerase II crystal are now in hand, crystals of the native enzyme, and cocrystals with DNA, with RNA, with both DNA and RNA in the transcriptionally active state, with TFIIB, with TFIIE, with the additional polymerase subunits RPB4 and RPB7, and with the tight-binding inhibitor a-amanitin. Recent progress includes a low resolution envelope and phases to 6.5 ¿, and the recent collection of several novel heavy atom cluster complexed with RNA Pol II. The prognosis is now very good for the rapid achievement of a high resolution structure.