A transposable element in a NAC gene is associated with drought tolerance in maize seedlings.
A transposable element in a NAC gene is associated with drought tolerance in maize seedlings.
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DOI：
10.1038/ncomms9326
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发表时间：
2015-09-21
影响因子：
16.6
通讯作者：
Qin F
中科院分区：
文献类型：
--
作者：
Mao H;Wang H;Liu S;Li Z;Yang X;Yan J;Li J;Tran LS;Qin F
干旱是全球玉米生产的主要制约因素。了解玉米耐旱性自然变异的遗传基础可能有助于改善栽培种质的这一性状。在这里，通过全基因组关联研究，我们发现插入 NAC 基因 (ZmNAC111) 启动子中的微型反向重复转座元件 (MITE) 与玉米耐旱性的自然变异显着相关。当在拟南芥中异源表达时，82 bp MITE 通过 RNA 指导的 DNA 甲基化和 H3K9 二甲基化抑制 ZmNAC111 的表达。增加转基因玉米中 ZmNAC111 的表达可增强幼苗期的耐旱性，提高水分利用效率，并在水分胁迫下诱导干旱响应基因的上调。 ZmNAC111 启动子中的 MITE 插入似乎发生在玉米驯化并在温带种质中传播之后。 MITE 插入的鉴定提供了对玉米耐旱性自然变异的遗传基础的深入了解。 干旱是玉米产量损失的主要原因，了解耐旱性自然变异的遗传决定因素可能有助于育种计划培育出更耐旱的品种。在这里，毛等人。鉴定出 NAC 转录因子中的 MITE 转座子插入，这与耐旱性的自然变异相关。
Drought represents a major constraint on maize production worldwide. Understanding the genetic basis for natural variation in drought tolerance of maize may facilitate efforts to improve this trait in cultivated germplasm. Here, using a genome-wide association study, we show that a miniature inverted-repeat transposable element (MITE) inserted in the promoter of a NAC gene (ZmNAC111) is significantly associated with natural variation in maize drought tolerance. The 82-bp MITE represses ZmNAC111 expression via RNA-directed DNA methylation and H3K9 dimethylation when heterologously expressed in Arabidopsis. Increasing ZmNAC111 expression in transgenic maize enhances drought tolerance at the seedling stage, improves water-use efficiency and induces upregulation of drought-responsive genes under water stress. The MITE insertion in the ZmNAC111 promoter appears to have occurred after maize domestication and spread among temperate germplasm. The identification of this MITE insertion provides insight into the genetic basis for natural variation in maize drought tolerance. Drought is a major cause of yield loss in maize and understanding the genetic determinants of natural variation in drought tolerance may aid breeding programs produce more tolerant varieties. Here, Mao et al. identify a MITE transposon insertion in a NAC transcription factor, which is associated with natural variation in drought tolerance.