Identification of a genomic region controlling thermotolerance at flowering in maize using a combination of whole genomic re-sequencing and bulked segregant analysis
Identification of a genomic region controlling thermotolerance at flowering in maize using a combination of whole genomic re-sequencing and bulked segregant analysis
复制标题
结合全基因组重测序和批量分离分析，鉴定控制玉米开花时耐热性的基因组区域。
DOI：
10.1007/s00122-020-03632-x
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发表时间：
2020-06-13
影响因子：
5.4
通讯作者：
Li, Peijin
中科院分区：
文献类型：
--
作者：
Zeng, Wei;Shi, Jian;Li, Peijin
通过全基因组重测序和群体分离分析相结合，在玉米中鉴定了一个控制开花期耐热性的新基因组区域。极端高温发生频率的增加给玉米整个生命周期的发育带来了极大的威胁，尤其是开花期。然而，玉米开花耐热性的遗传基础仍然知之甚少。本研究利用Abe 2与B73杂交产生的F（2：8）重组自交系（RIL）群体，对耐热玉米生态型Abe 2进行了鉴定，并对其遗传基础进行了剖析。在田间条件下，Abe 2和B73在35 ℃以上连续高温胁迫17 d后，表现出明显的叶片焦枯表型。为了鉴定与表型变异相关的基因组区域，我们应用了全基因组重测序和混合分离分析的组合，并揭示了两个亲本系之间的10，316，744个SNP和1，488，302个InDel，以及2，693，054个SNP和313个InDel，RIL耐热个体和敏感个体产生的两个DNA池之间存在757个InDel，其中108，655个和17，853个SNP可能导致非同义变异。最后，在1号染色体上的7.41 Mb的基因组区域被确定，并注释了7个候选基因参与高温相关的胁迫反应。编码丝氨酸/苏氨酸蛋白激酶的候选基因Zm 00001 d 033339被认为是最有可能通过脱落酸（阿坝）途径（KO 04075）参与气孔运动（GO：0010119）而促进开花期耐热性的基因。本研究为玉米开花期耐热性基因的克隆和改良育种提供了可能。
Key message A novel genomic region controlling thermotolerance at flowering was identified by the combination of whole genomic re-sequencing and bulked segregant analysis in maize. The increasing frequency of extreme high temperature has brought a great threat to the development of maize throughout its life cycle, especially during the flowering phase. However, the genetic basis of thermotolerance at flowering in maize remains poorly understood. Here, we characterized a thermotolerant maize ecotype Abe2 and dissected its genetic basis using a F(2:8)recombinant inbred line (RIL) population generated from a cross between Abe2 and B73. After continuous high temperature stress above 35 degrees C for 17 days, Abe2 and B73 show distinct leaf scorching phenotype under field conditions. To identify the genomic regions associated with the phenotypic variation, we applied a combination of whole genomic re-sequencing and bulked segregant analysis, and revealed 10,316,744 SNPs and 1,488,302 InDels between the two parental lines, and 2,693,054 SNPs and 313,757 InDels between the two DNA pools generated from the thermos-tolerant and the sensitive individuals of the RIL, of which, 108,655 and 17,853 SNPs may cause nonsynonymous variations. Finally, a 7.41 Mb genomic region on chromosome 1 was identified, and 7 candidate genes were annotated to participate in high temperature-related stress response. A candidate geneZm00001d033339encoding a serine/threonine protein kinase was proposed to be the most likely causative gene contributing to the thermotolerance at flowering by involving in stomatal movement (GO: 0010119) via Abscisic acid (ABA) pathway (KO04075). This work could provide an opportunity for gene cloning and pyramiding breeding to improve thermotolerance at flowering in maize.