Non-SMC elements 1 and 3 are required for early embryo and seedling development in Arabidopsis.
Non-SMC elements 1 and 3 are required for early embryo and seedling development in Arabidopsis.
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非 SMC 元件 1 和 3 是拟南芥早期胚胎和幼苗发育所必需的
DOI：
10.1093/jxb/erx016
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发表时间：
2017-02-01
影响因子：
6.9
通讯作者：
Zhao J
中科院分区：
文献类型：
--
作者：
Li G;Zou W;Jian L;Qian J;Deng Y;Zhao J
&NA;从合子开始的早期胚发育是种子形成的重要阶段，而幼苗发育是个体植物形成的开始。AtNSE 1和AtNSE 3是染色体结构维持（SMC）5/6复合体的亚基，已被鉴定为非SMC元件，但它们在拟南芥生长和发育中的功能仍然未知。在这项研究中，我们发现AtNSE 1和AtNSE 3的功能丧失导致早期胚胎发育的严重缺陷。部分互补的突变体表明，突变体幼苗的发育受到抑制，染色体在分裂后期出现断裂，细胞周期延迟在G2/M期，从而导致核内复制的发生。此外，在nse 1和nse 3突变体中发生了大量的DNA双链断裂（DSB），并且在用DSB诱导剂化合物处理植物后，AtNSE 1和AtNSE 3的表达上调，表明AtNSE 1和AtNSE 3在DNA损伤修复中具有作用。因此，我们得出结论，AtNSE 1和AtNSE 3促进DSB修复，并有助于维持有丝分裂细胞的基因组稳定性和细胞分裂。因此，我们认为AtNSE 1和AtNSE 3可能是维持正常早期胚胎和胚胎后发育的关键因素。
&NA; Early embryo development from the zygote is an essential stage in the formation of the seed, while seedling development is the beginning of the formation of an individual plant. AtNSE1 and AtNSE3 are subunits of the structural maintenance of chromosomes (SMC) 5/6 complex and have been identified as non‐SMC elements, but their functions in Arabidopsis growth and development remain as yet unknown. In this study, we found that loss of function of AtNSE1 and AtNSE3 led to severe defects in early embryo development. Partially complemented mutants showed that the development of mutant seedlings was inhibited, that chromosome fragments occurred during anaphase, and that the cell cycle was delayed at G2/M, which led to the occurrence of endoreduplication. Further, a large number of DNA double‐strand breaks (DSBs) occurred in the nse1 and nse3 mutants, and the expression of AtNSE1 and AtNSE3 was up‐regulated following treatment of the plants with DSB inducer compounds, suggesting that AtNSE1 and AtNSE3 have a role in DNA damage repair. Therefore, we conclude that AtNSE1 and AtNSE3 facilitate DSB repair and contribute to maintaining genome stability and cell division in mitotic cells. Thus, we think that AtNSE1 and AtNSE3 may be crucial factors for maintaining proper early embryonic and post‐embryonic development.