DNA ligase III promotes alternative nonhomologous end-joining during chromosomal translocation formation.
DNA ligase III promotes alternative nonhomologous end-joining during chromosomal translocation formation.
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DOI：
10.1371/journal.pgen.1002080
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发表时间：
2011-06
期刊：
影响因子：
4.5
通讯作者：
Jasin M
中科院分区：
文献类型：
--
作者：
Simsek D;Brunet E;Wong SY;Katyal S;Gao Y;McKinnon PJ;Lou J;Zhang L;Li J;Rebar EJ;Gregory PD;Holmes MC;Jasin M
非同源末端连接(NHEJ)是体细胞染色体易位和其他基因组重排的主要DNA修复途径。典型的NHEJ途径，包括DNA连接酶IV(Lig4)，抑制了基因组的不稳定性和染色体易位，导致了一种定义不明确的替代NHEJ(ALT-NHEJ)途径产生这些重排的概念。在这里，我们研究了小鼠细胞染色体易位形成所需的DNA连接酶。哺乳动物除了Lig4外，还有另外两种DNA连接酶，Lig1和Lig3。由于Lig3的缺失会导致细胞死亡，因为它需要线粒体，所以我们使用了最近开发的核Lig3缺陷但线粒体DNA连接酶活性恢复的细胞系。此外，锌指核酸内切酶被用来在内源基因座产生DNA断裂以诱导易位。与导致易位频率增加的Lig4缺乏症不同，在没有Lig3的情况下，易位频率降低。与野生型或Lig4缺陷细胞不同，Lig3缺陷细胞中的残余易位并不显示出在断点连接使用预先存在的微同源的偏见，这与ALT-NHEJ因Lig3缺失而受损的概念一致。相比之下，野生型细胞中Lig1的缺失不会减少易位或影响微同源基因的使用。然而，在Lig1基因敲除后，Lig3缺陷细胞中的易位进一步减少，这表明存在两条ALT-NHEJ途径，一条偏向微同源使用并需要Lig3，另一条备份路径不依赖微同源并利用Lig1。染色体重排与许多肿瘤类型有关，因为它们是影响癌症启动和进展的基因突变的一种方式。一种类型的重排是染色体易位，即两个不同染色体的部分结合在一起。易位虽然不常见，但当两条染色体都发生断裂，来自不同染色体的末端连接而不是来自同一条染色体的两端结合时，易位就会发生。人类和小鼠细胞有三种已知的DNA连接酶，它们催化DNA末端的连接(Lig1、Lig3和Lig4)。Lig4对于将正确的末端连接在一起从而抑制易位非常重要。在这份报告中，我们研究了另外两种DNA连接酶在一个新的小鼠细胞系统中的作用。Lig3被发现是有效的染色体易位形成所必需的，但在没有它的情况下，Lig1可以替代，尽管效率较低，而且尽管两种DNA连接酶的连接特性不同。这些研究确定了这种类型的基因组重排中三种DNA连接酶的等级。
Nonhomologous end-joining (NHEJ) is the primary DNA repair pathway thought to underlie chromosomal translocations and other genomic rearrangements in somatic cells. The canonical NHEJ pathway, including DNA ligase IV (Lig4), suppresses genomic instability and chromosomal translocations, leading to the notion that a poorly defined, alternative NHEJ (alt-NHEJ) pathway generates these rearrangements. Here, we investigate the DNA ligase requirement of chromosomal translocation formation in mouse cells. Mammals have two other DNA ligases, Lig1 and Lig3, in addition to Lig4. As deletion of Lig3 results in cellular lethality due to its requirement in mitochondria, we used recently developed cell lines deficient in nuclear Lig3 but rescued for mitochondrial DNA ligase activity. Further, zinc finger endonucleases were used to generate DNA breaks at endogenous loci to induce translocations. Unlike with Lig4 deficiency, which causes an increase in translocation frequency, translocations are reduced in frequency in the absence of Lig3. Residual translocations in Lig3-deficient cells do not show a bias toward use of pre-existing microhomology at the breakpoint junctions, unlike either wild-type or Lig4-deficient cells, consistent with the notion that alt-NHEJ is impaired with Lig3 loss. By contrast, Lig1 depletion in otherwise wild-type cells does not reduce translocations or affect microhomology use. However, translocations are further reduced in Lig3-deficient cells upon Lig1 knockdown, suggesting the existence of two alt-NHEJ pathways, one that is biased toward microhomology use and requires Lig3 and a back-up pathway which does not depend on microhomology and utilizes Lig1. Chromosomal rearrangements are associated with many tumor types, as they are one way in which genes affecting cancer initiation and progression become mutated. One type of rearrangement is a chromosomal translocation, in which parts of two different chromosomes join together. Although infrequent, translocations occur when both chromosomes undergo breakage and the ends from different chromosomes join rather than the two ends from the same chromosome. Human and mouse cells have three known DNA ligases which catalyze the joining of DNA ends (Lig1, Lig3, and Lig4). Lig4 is important for joining the correct ends together, thereby suppressing translocations. In this report, the role of the other two DNA ligases is examined in a novel mouse cell system. Lig3 is found to be required for efficient chromosomal translocation formation, but in its absence Lig1 can substitute, although less efficiently and although the joining characteristics of the two DNA ligases differ. These studies define the hierarchy of the three DNA ligases in this type of genomic rearrangement.
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影响因子：
64.5
作者：
Goldberg AD;Banaszynski LA;Noh KM;Lewis PW;Elsaesser SJ;Stadler S;Dewell S;Law M;Guo X;Li X;Wen D;Chapgier A;DeKelver RC;Miller JC;Lee YL;Boydston EA;Holmes MC;Gregory PD;Greally JM;Rafii S;Yang C;Scambler PJ;Garrick D;Gibbons RJ;Higgs DR;Cristea IM;Urnov FD;Zheng D;Allis CD
通讯作者：
Allis CD
影响因子：
46.9
作者：
Hockemeyer, Dirk;Soldner, Frank;Beard, Caroline;Gao, Qing;Mitalipova, Maisam;DeKelver, Russell C.;Katibah, George E.;Amora, Ranier;Boydston, Elizabeth A.;Zeitler, Bryan;Meng, Xiangdong;Miller, Jeffrey C.;Zhang, Lei;Rebar, Edward J.;Gregory, Philip D.;Urnov, Fyodor D.;Jaenisch, Rudolf
通讯作者：
Jaenisch, Rudolf
DOI：
10.1084/jem.20020851
发表时间：
2002-08-19
期刊：
The Journal of experimental medicine
影响因子：
--
作者：
Difilippantonio MJ;Petersen S;Chen HT;Johnson R;Jasin M;Kanaar R;Ried T;Nussenzweig A
通讯作者：
Nussenzweig A
DOI：
10.1073/pnas.0915067107
发表时间：
2010-02-16
影响因子：
11.1
作者：
Boboila, Cristian;Jankovic, Mila;Alt, Frederick W.
通讯作者：
Alt, Frederick W.
影响因子：
5.3
作者：
CALDECOTT, KW;MCKEOWN, CK;THOMPSON, LH
通讯作者：
THOMPSON, LH