A Lynch syndrome-associated mutation at a Bergerat ATP-binding fold destabilizes the structure of the DNA mismatch repair endonuclease MutL
A Lynch syndrome-associated mutation at a Bergerat ATP-binding fold destabilizes the structure of the DNA mismatch repair endonuclease MutL
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Bergerat ATP 结合折叠处的林奇综合征相关突变破坏了 DNA 错配修复核酸内切酶 MutL 结构的稳定性
DOI：
10.1074/jbc.ra120.013576
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发表时间：
2020
影响因子：
4.8
通讯作者：
Yano Takato
中科院分区：
文献类型：
--
作者：
Izuhara Keisuke;Fukui Kenji;Murakawa Takeshi;Baba Seiki;Kumasaka Takashi;Uchiyama Kazuhisa;Yano Takato
在人类中，编码DNA错配修复内切酶MutL同源基因的突变导致一种被称为Lynch综合征的遗传性癌症。在这里，我们确定了嗜热的富细菌（aqMutL）与ATP类似物在1.69-1.73 Å络合的MutL的n端结构域（NTD）的晶体结构。该结构显示出与人类MutL同源物的显著结构相似性，减数分裂后分离增加2 （PMS2）。我们将人类PMS2中临床发现的5个Lynch综合征相关突变引入aqMutL NTD，并研究了这些蛋白质变体的蛋白质稳定性、atp酶活性和dna结合能力。在研究的突变中，残基Ser34获得了最意想不到的结果。Ser34 （PMS2中的Ser46）位于先前鉴定的Bergerat atp结合褶上。我们发现S34I aqMutL NTD保留了atp酶和dna结合活性。有趣的是，CD光谱和胰蛋白酶限制蛋白水解表明S34I NTD的二级结构元件被破坏，使aqMutL NTD的整体结构不稳定。与此一致的是，重组人PMS2 S46I NTD在宿主大肠杆菌细胞中很容易被消化。此外，其他突变导致dna结合或atp酶活性降低。综上所述，我们以耐热的aqMutL蛋白为模型分子，实验确定了突变对MutL内切酶的影响；我们讨论了人类PMS2相应突变的病理作用。
In humans, mutations in genes encoding homologs of the DNA mismatch repair endonuclease MutL cause a hereditary cancer that is known as Lynch syndrome. Here, we determined the crystal structures of the N-terminal domain (NTD) of MutL from the thermophilic eubacteriumAquifex aeolicus(aqMutL) complexed with ATP analogs at 1.69–1.73 Å. The structures revealed significant structural similarities to those of a human MutL homolog, postmeiotic segregation increased 2 (PMS2). We introduced five Lynch syndrome-associated mutations clinically found in human PMS2 into the aqMutL NTD and investigated the protein stability, ATPase activity, and DNA-binding ability of these protein variants. Among the mutations studied, the most unexpected results were obtained for the residue Ser34. Ser34 (Ser46 in PMS2) is located at a previously identified Bergerat ATP-binding fold. We found that the S34I aqMutL NTD retains ATPase and DNA-binding activities. Interestingly, CD spectrometry and trypsin-limited proteolysis indicated the disruption of a secondary structure element of the S34I NTD, destabilizing the overall structure of the aqMutL NTD. In agreement with this, the recombinant human PMS2 S46I NTD was easily digested in the hostEscherichia colicells. Moreover, other mutations resulted in reduced DNA-binding or ATPase activity. In summary, using the thermostable aqMutL protein as a model molecule, we have experimentally determined the effects of the mutations on MutL endonuclease; we discuss the pathological effects of the corresponding mutations in human PMS2.
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遗传性非息肉病性结直肠癌（林奇综合征 I 和 II）。
影响因子：
6.2
作者：
H. Lynch;W. Kimberling;W. Albano;J. Lynch;Karen A. Biscone;G. Schuelke;A. Sandberg;M. Lipkin;E. Deschner;Y. Mikol;R. Elston;J. Bailey;B. Danes
通讯作者：
B. Danes
影响因子：
64.5
作者：
FISHEL, R;LESCOE, MK;KOLODNER, R
通讯作者：
KOLODNER, R
影响因子：
64.5
作者：
Ban, C;Junop, M;Yang, W
通讯作者：
Yang, W
DOI：
10.1016/j.bbapap.2017.06.024
发表时间：
2017-09-01
影响因子：
3.2
作者：
Fukui, Kenji;Iino, Hitoshi;Yano, Takato
通讯作者：
Yano, Takato
遗传性非息肉病性结直肠癌以及 hPMS2 和 hEXO1 突变的作用
影响因子：
3.5
作者：
E. Thompson;C. Meldrum;R. Crooks;M. McPhillips;L. Thomas;A. Spigelman;Rodney J. Scott;Rodney J. Scott
通讯作者：
Rodney J. Scott