5-Formylcytosine mediated DNA-protein cross-links block DNA replication and induce mutations in human cells.
5-Formylcytosine mediated DNA-protein cross-links block DNA replication and induce mutations in human cells.
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DOI：
10.1093/nar/gky444
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发表时间：
2018-07-27
影响因子：
14.9
通讯作者：
Tretyakova NY
中科院分区：
文献类型：
--
作者：
Ji S;Fu I;Naldiga S;Shao H;Basu AK;Broyde S;Tretyakova NY
5 - 醛基胞嘧啶（5fC）是一种表观遗传DNA修饰，由TET蛋白介导的5 - 甲基胞嘧啶氧化产生。我们最近报道，在活细胞中，5fC与组蛋白形成可逆的DNA - 蛋白质交联物（DPCs）（Ji等人，2017年，《德国应用化学国际版》，56卷：14130 - 14134）。现在，我们研究了5fC介导的DPCs对DNA复制的影响。含有5fC与含赖氨酸的蛋白质及肽之间位点特异性DPCs的合成DNA双链，在人跨损伤合成DNA聚合酶η和κ存在的情况下进行引物延伸实验。我们发现，含有组蛋白H2A或H4的DPCs完全抑制DNA复制，但当这些蛋白质进行蛋白酶消化后，复制阻断被解除。两种聚合酶均以易错方式绕过与11聚体或31聚体肽的交联，诱导靶向的C→T转换和 - 1缺失。当含有5fC - 肽交联的质粒在人胚肾（HEK）293T细胞中复制时，观察到类似类型的突变。对与人类聚合酶η和κ结合的11聚体肽 - dC交联进行分子模拟显示，该肽很好地适配于DNA大沟一侧，并且修饰的dC在聚合酶活性位点通过摆动碱基配对与进入的dATP形成稳定的错配。
5-Formylcytosine (5fC) is an epigenetic DNA modification introduced via TET protein-mediated oxidation of 5-methyl-dC. We recently reported that 5fC form reversible DNA–protein conjugates (DPCs) with histone proteins in living cells (Ji et al. (2017) Angew. Chem. Int. Ed., 56:14130–14134). We now examined the effects of 5fC mediated DPCs on DNA replication. Synthetic DNA duplexes containing site-specific DPCs between 5fC and lysine-containing proteins and peptides were subjected to primer extension experiments in the presence of human translesion synthesis DNA polymerases η and κ. We found that DPCs containing histones H2A or H4 completely inhibited DNA replication, but the replication block was removed when the proteins were subjected to proteolytic digestion. Cross-links to 11-mer or 31-mer peptides were bypassed by both polymerases in an error-prone manner, inducing targeted C→T transitions and –1 deletions. Similar types of mutations were observed when plasmids containing 5fC-peptide cross-links were replicated in human embryonic kidney (HEK) 293T cells. Molecular simulations of the 11-mer peptide-dC cross-links bound to human polymerases η and κ revealed that the peptide fits well on the DNA major groove side, and the modified dC forms a stable mismatch with incoming dATP via wobble base pairing in the polymerase active site.
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影响因子：
14.9
作者：
Lavery R;Moakher M;Maddocks JH;Petkeviciute D;Zakrzewska K
通讯作者：
Zakrzewska K
影响因子：
64.5
作者：
Duxin JP;Dewar JM;Yardimci H;Walter JC
通讯作者：
Walter JC
影响因子：
2.9
作者：
Colis, Laureen C.;Raychaudhury, Paromita;Basu, Ashis K.
通讯作者：
Basu, Ashis K.
影响因子：
4.8
作者：
Barker, S;Weinfeld, M;Murray, D
通讯作者：
Murray, D
影响因子：
4.8
作者：
Baker, David J.;Wuenschell, Gerald;O'Connor, Timothy R.
通讯作者：
O'Connor, Timothy R.