High-resolution insight into recombination events at the SD1 locus in rice
High-resolution insight into recombination events at the SD1 locus in rice
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对水稻 SD1 基因座重组事件的高分辨率洞察。
DOI：
10.1111/tpj.14154
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发表时间：
2019
期刊：
影响因子：
7.2
通讯作者：
Yang Sihai
中科院分区：
文献类型：
--
作者：
Jia Xianqing;Zhang Yadong;Zhang Qijun;Zhao Qingyong;Traw Milton Brian;Wang Long;Tian Dacheng;Wang Cailin;Yang Sihai
减数分裂过程中的突变在基因组进化中起着重要的作用，它将现有的遗传变异重新组合成新的组合，并有可能恢复丢失的祖先基因型。虽然交叉（CO）事件已经得到了很好的研究，但代表染色体之间非互惠信息传递的基因转换事件（GC）记录不多，并且由于其相对较小的转换束大小而难以检测。在这里，我们记录了这些GC事件及其在含有SD 1基因的水稻中的重要位点的表型效应，其中多个缺陷等位基因在20世纪60年代的“绿色革命”中导致了水稻的半矮秆表型。在这里，两个缺陷的物理分离允许重组以产生野生型SD 1基因，然后可以将植物高度用作报告基因。通过从携带这些不同缺陷等位基因的两个半矮秆品种杂交中筛选18000个F2后代，我们检测到24个GC事件，表明在水稻单个减数分裂周期中每代每个标记的转化率约为3.3 × 10 - 4。此外，我们的数据表明，插入缺失和单核苷酸多态性（SNP）在GC率方面没有显著差异，至少在SD 1位点。我们的研究结果提供了强有力的证据表明，GC本身可以恢复通过突变丢失的祖先表型。这种GC检测方法可能广泛适用于其他表型相关功能基因的天然或人工等位基因，这些基因在其他植物基因组中丰富。
Recombination during meiosis plays an important role in genome evolution by reshuffling existing genetic variations into fresh combinations with the possibility of recovery of lost ancestral genotypes. While crossover (CO) events have been well studied, gene conversion events (GCs), which represent non‐reciprocal information transfer between chromosomes, are poorly documented and difficult to detect due to their relatively small converted tract size. Here, we document these GC events and their phenotypic effects at an important locus in rice containing theSD1gene, where multiple defective alleles contributed to the semi‐dwarf phenotype of rice in the ‘Green Revolution’ of the 1960s. Here, physical separation of two defects allows recombination to generate the wild‐typeSD1gene, for which plant height can then be used as a reporter. By screening 18 000 F2progeny from a cross between two semi‐dwarf cultivars that carry these different defective alleles, we detected 24 GC events, indicating a conversion rate of ~3.3 × 10−4per marker per generation in a single meiotic cycle in rice. Furthermore, our data show that indels and single‐nucleotide polymorphisms (SNPs) do not differ significantly in GC rates, at least at theSD1locus. Our results provide strong evidence that GC by itself can regain an ancestral phenotype that was lost through mutation. This GC detection approach is likely to be broadly applicable to natural or artificial alleles of other phenotype‐related functional genes, which are abundant in other plant genomes.