Regulation of interference-sensitive crossover distribution ensures crossover assurance in Arabidopsis.
Regulation of interference-sensitive crossover distribution ensures crossover assurance in Arabidopsis.
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对干扰敏感的交叉分布的调节确保了拟南芥中的交叉保证。
DOI：
10.1073/pnas.2107543118
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
Wang Yingxiang
中科院分区：
文献类型：
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作者：
Li Xiang;Zhang Jun;Huang Jiyue;Xu Jing;Chen Zhiyu;Copenhaver Gregory P;Wang Yingxiang
在减数分裂期间，通常需要交换（CO）以确保忠实的染色体分离。尽管每对染色体之间至少需要一个CO，但由于称为CO干扰的现象，紧密间隔的双CO通常代表性不足。与小家鼠和酿酒酵母一样，拟南芥具有干扰敏感型（I类）和干扰不敏感型（II类）CO。然而，控制CO分布的潜在机制在很大程度上仍然是难以捉摸的。AtMUS81和AtFANCD2促进II类CO的形成。使用AtHEI10和AtMLH1免疫染色，I类CO的两个标志物，我们表明，AtFANCD2，但不是AtMUS81是所需的正常I类CO染色体之间的分布。耗尽AtFANCD2导致CO分布模式介于野生型和泊松分布之间。此外，在Atfancm，Atfigl 1和Atrmi 1突变体中，我们观察到了与Atfancd 2惊人相似的I类CO分布模式。令人惊讶的是，我们发现AtFANCD 2在Atfancm中调节CO频率的作用与Atfigl 1或Atrmi 1相反。和AtRMI 1通过不同的机制调节II类CO的频率，它们在控制I类CO在染色体中的分布方面具有相似的作用。
During meiosis, crossovers (COs) are typically required to ensure faithful chromosomal segregation. Despite the requirement for at least one CO between each pair of chromosomes, closely spaced double COs are usually underrepresented due to a phenomenon called CO interference. LikeMus musculusandSaccharomyces cerevisiae,Arabidopsis thalianahas both interference-sensitive (Class I) and interference-insensitive (Class II) COs. However, the underlying mechanism controlling CO distribution remains largely elusive. Both AtMUS81 and AtFANCD2 promote the formation of Class II CO. Using both AtHEI10 and AtMLH1 immunostaining, two markers of Class I COs, we show that AtFANCD2 but not AtMUS81 is required for normal Class I CO distribution among chromosomes. DepletingAtFANCD2leads to a CO distribution pattern that is intermediate between that of wild-type and a Poisson distribution. Moreover, inAtfancm,Atfigl1, andAtrmi1mutants where increased Class II CO frequency has been reported previously, we observe Class I CO distribution patterns that are strikingly similar toAtfancd2.Surprisingly, we found that AtFANCD2 plays opposite roles in regulating CO frequency inAtfancmcompared with either inAtfigl1orAtrmi1.Together, these results reveal that although AtFANCD2, AtFANCM, AtFIGL1, and AtRMI1 regulate Class II CO frequency by distinct mechanisms, they have similar roles in controlling the distribution of Class I COs among chromosomes.