Functional residues on the surface of the N-terminal domain of yeast Pms1.
Functional residues on the surface of the N-terminal domain of yeast Pms1.
复制标题
DOI：
10.1016/j.dnarep.2010.01.010
复制
发表时间：
2010-04-04
期刊：
影响因子：
3.8
通讯作者：
Kunkel TA
中科院分区：
文献类型：
--
作者：
Arana ME;Holmes SF;Fortune JM;Moon AF;Pedersen LC;Kunkel TA
酿酒酵母MutLα是Mlh 1和Pms 1的异源二聚体，参与DNA错配修复（MMR）。这两种蛋白质都具有弱保守的C-末端区域（CTD），其中Pms 1的CTD具有必需的核酸内切酶活性。这些蛋白质还具有保守的N-末端结构域（NTD），其结合和水解ATP并结合DNA。为了更好地了解Pms 1的功能以及与DNA和/或其他蛋白质的潜在相互作用，我们解析了酵母Pms 1（yPms 1）NTD的2.5 Å晶体结构。其结构与E. coliMutL和人PMS 2的氨基酸序列，包括参与ATP结合和水解的位点。该结构揭示了许多保守的带正电荷的表面残基，其不与NTD中的其他残基相互作用，因此是与DNA、CTD和/或其他蛋白质相互作用的候选者。当这些被谷氨酸取代时，几次取代导致酵母菌株突变率升高。两个替换也导致NTD在体外DNA结合亲和力降低，表明这些残基有助于DNA结合，这对错配修复很重要。突变率升高也是由于表面残基置换不影响DNA结合，这表明这些保守残基具有其他功能，可能涉及与其他MMR蛋白的相互作用。
Saccharomyces cerevisiae MutLα is a heterodimer of Mlh1 and Pms1 that participates in DNA mismatch repair (MMR). Both proteins have weakly conserved C-terminal regions (CTD), with the CTD of Pms1 harboring an essential endonuclease activity. These proteins also have conserved N-terminal domains (NTD) that bind and hydrolyze ATP and bind to DNA. To better understand Pms1 functions and potential interactions with DNA and/or other proteins, we solved the 2.5Å crystal structure of yeast Pms1 (yPms1) NTD. The structure is similar to thehomologous NTDs of E. coli MutL and human PMS2, including the site involved in ATP binding and hydrolysis. The structure reveals a number of conserved, positively charged surface residues that do not interact with other residues in the NTD and are therefore candidates for interactions with DNA, with the CTD and/or with other proteins. When these were replaced with glutamate, several replacements resulted in yeast strains with elevated mutation rates. Two replacements also resulted in NTDs with decreased DNA binding affinity in vitro, suggesting that these residues contribute to DNA binding that is important for mismatch repair. Elevated mutation rates also resulted from surface residue replacements that did not affect DNA binding, suggesting that these conserved residues serve other functions, possibly involving interactions with other MMR proteins.
登录
查看更多内容
影响因子：
5.6
作者：
Bowers, J;Tran, PT;Alani, E
通讯作者：
Alani, E
影响因子：
64.5
作者：
Ban, C;Junop, M;Yang, W
通讯作者：
Yang, W
影响因子：
4.8
作者：
Cannavo, Elda;Gerrits, Bertran;Jiricny, Josef
通讯作者：
Jiricny, Josef
DOI：
10.1107/s0907444998003254
发表时间：
1998-09-01
期刊：
ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY
影响因子：
--
作者：
Brunger, AT;Adams, PD;Warren, GL
通讯作者：
Warren, GL
影响因子：
3.6
作者：
Kan, Rui;Sun, Xianfei;Cohen, Paula E.
通讯作者：
Cohen, Paula E.