Characterisation of novel functions of the active centre of RNA polymerase

基因信息的实现需要将DNA中编码的信息复制到RNA转录中。之后，这些以RNA形式存在的信息要么被细胞直接使用，要么在翻译过程中被解码成蛋白质。在所有生物中，转录是由多亚单位RNA聚合酶执行的，这些酶在从细菌到人类的进化中高度保守。尽管对RNA聚合酶的研究已经活跃了30年，其中大部分是在过去的十年里，但控制其功能的机制仍然不完全清楚。特别有趣但同时又鲜为人知的是RNA聚合酶活性中心的功能，这是地球上最古老的蛋白质活性中心之一。确保转录的准确性和可加工性的机制仍不清楚。此外，它甚至似乎并不是所有能被RNA聚合酶活性中心催化的反应都是已知的。从应用的角度来看，确定RNA聚合酶的活性中心对于药物发现也很重要，因为它是有效抗生素的靶标。最近，我们描述了RNA聚合酶活性中心的几个新特征，这些特征对于全面了解其分子功能非常重要。在这项提案中，我们将描述新发现的RNA连接反应的特征，并探索其在RNA聚合酶功能中的意义。我们还将研究负责RNA聚合酶活性中心底物的协调和稳定的复杂机制，以及在RNA聚合酶执行的所有反应中催化之前活性中心的构象开关。最后，我们将寻找以前未知的机制，以及RNA聚合酶的新反应。这将有助于全面了解转录过程中涉及的机制。

Realisation of genetic information requires the copying of information coded in DNA into RNA, transcription. Afterwards this information, in the form of RNA, is either directly used by the cell or decoded into proteins during translation. In all living organisms transcription is performed by multisubunit RNA polymerases, enzymes highly conserved in evolution from bacteria to humans. Though RNA polymerase has been actively investigated for 30 years, most heavily during the last decade, the mechanisms that govern its functions are still not fully understood. Especially interesting and at the same time obscure is the functioning of the active centre of RNA polymerase, one of the most ancient protein active centres on Earth. The mechanisms ensuring accuracy, and processivity of transcription are still unclear. Furthermore, it even appears that not all of the reactions that can be catalysed by the RNA polymerase active centre are known. From an applied perspective, characterisation of the active centre of RNA polymerase is also important for drug discovery, since it is the target for potent antibiotics. Recently we have described several new features of the active centre of RNA polymerase that are important for complete understanding of its molecular function. In this proposal we will characterise the newly discovered RNA ligation reaction and search for its significance in RNA polymerase function. We will also investigate the complex mechanisms responsible for coordination and stabilisation of substrates in the active centre of RNA polymerase, and for the conformational switches in the active centre that precede catalysis in all of the reactions performed by RNA polymerase. Finally, we will search for previously unrecognised mechanisms, and new reactions of RNA polymerase. This will help to build a comprehensive picture of the mechanisms involved in transcription.