Temporally uncoupled signal and coding joint formation in human V(D)J recombination.
Temporally uncoupled signal and coding joint formation in human V(D)J recombination.
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DOI：
10.1016/j.molimm.2020.10.010
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发表时间：
2020-12
影响因子：
3.6
通讯作者：
Lieber MR
中科院分区：
文献类型：
--
作者：
Hsieh CL;Okitsu CY;Lieber MR
在脊椎动物抗原受体基因重排中，V(D)J重组事件可通过缺失或倒置发生。对于删除事件，信号接头从基因组中删除。近一半的免疫球蛋白轻链基因以倒位方式进行V(D)J重组，并且必须同时形成信号和编码关节以保持染色体的完整性。但是考虑到在V(D)J重组过程中发生的pre-B和pre-T细胞死亡的数量不确定，这两个关节完成的效率是未知的，信号与编码关节形成的相对效率（平衡）也是未知的。信号接头的形成只需要Ku和非同源DNA末端的DNA连接酶4 （XRCC4:DNA ligase 4）连接修复通路即可。编码接头的形成也需要这些蛋白，但还需要Artemis和DNA依赖性蛋白激酶打开发夹DNA编码端，这是RAG复合体产生的；由于发夹开口产生不兼容的3 '悬垂，需要进一步加工。一些末端加工酶的突变会影响一个关节，但对另一个关节影响很小。我们设计了一种精确的细胞分析方法，它没有任何细胞、酶或生化的选择性偏差，可以独立评估信号和编码关节的形成，并且可以检测到一个关节形成的中间体，而不是另一个。我们发现只有一个完整关节的中间体比两个完整关节的分子更丰富。这表明任何一个关节都可以独立于另一个关节形成，并且关节形成可能是一个相对缓慢的过程。
In vertebrate antigen receptor gene rearrangement, V(D)J recombination events can occur by deletion or by inversion. For deletional events, the signal joint is deleted from the genome. Nearly half of the immunoglobulin light chain genes undergo V(D)J recombination in an inversional manner, and both signal and coding joint formation must occur to retain chromosomal integrity. But given the undetermined amount of pre-B and pre-T cell death that occurs during V(D)J recombination, the efficiency with which both joints are completed is not known, nor is the relative efficiency (balance) of signal versus coding joint formation. Signal joint formation only requires Ku and XRCC4:DNA ligase 4 of the nonhomologous DNA end joining repair pathway. Coding joint formation requires these proteins as well, but in addition requires Artemis and DNA-dependent protein kinase to open the hairpin DNA coding ends, which the RAG complex generated; and further processing is required because the hairpin opening generates incompatible 3’ overhangs. Mutations in some of the end processing enzymes affect one, but only minimally the other joint. We have devised a precise cellular assay that does not have any cellular, enzymatic or biochemical selective bias to assess signal and coding joint formation independently, and it can detect intermediates for which one joint has formed but not the other. We find that intermediates with only one completed joint are more abundant than molecules with both joints completed. This indicates that either joint can form independent of the other and joint formation can be a relatively slow process.
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影响因子：
16
作者：
Jiang, H;Chang, FC;Desiderio, S
通讯作者：
Desiderio, S
影响因子：
14.9
作者：
Lu H;Schwarz K;Lieber MR
通讯作者：
Lieber MR
影响因子：
10.5
作者：
GAUSS, GH;LIEBER, MR
通讯作者：
LIEBER, MR
影响因子：
10.5
作者：
LIEBER, MR;HESSE, JE;GELLERT, M
通讯作者：
GELLERT, M
DOI：
10.4049/jimmunol.1501654
发表时间：
2016-04-01
期刊：
Journal of immunology (Baltimore, Md. : 1950)
影响因子：
--
作者：
Neal JA;Xu Y;Abe M;Hendrickson E;Meek K
通讯作者：
Meek K