Whitehouse A, Deeble J, Parmar R, Taylor G R, Markham A F, Meredith D M
Molecular Medicine Unit, University of Leeds, St. James's University Hospital, United Kingdom.
Biochem Biophys Res Commun. 1997 Apr 28;233(3):834-7. doi: 10.1006/bbrc.1997.6551.
The methyl-directed long patch repair pathway in Escherichia coli is involved in increasing the fidelity of replication specific repair of DNA polymerase incorporation errors. This pathway is mediated by three gene products, MutS, MutL, and MutH, which are conserved in higher eukaryotes. Mutations in human homologues of these proteins have been shown to be implicated in hereditary non-polyposis colorectal cancer (HNPCC). A MutS homologue has recently been identified in the extremely thermophilic bacterium, Thermus thermophilus. Here we describe analysis of the binding properties of this protein, which has indicated it can identify all specific base mismatches as well as one, two and three base pair insertion/deletion mutations. We therefore believe this protein may be generally useful for applications involving mismatch detection.
大肠杆菌中的甲基导向长片段修复途径参与提高DNA聚合酶掺入错误的复制特异性修复的保真度。该途径由三种基因产物介导，即MutS、MutL和MutH，它们在高等真核生物中是保守的。这些蛋白质的人类同源物中的突变已被证明与遗传性非息肉病性结直肠癌（HNPCC）有关。最近在嗜热栖热菌这种极端嗜热细菌中鉴定出了一种MutS同源物。在此，我们描述了对该蛋白质结合特性的分析，结果表明它可以识别所有特定的碱基错配以及一、二和三个碱基对的插入/缺失突变。因此，我们认为这种蛋白质可能普遍适用于涉及错配检测的应用。
