【摘要】 干旱严重影响玉米产量和品质,因此挖掘干旱响应基因,解析其遗传机制,对培育抗旱品种具有重要的理论意义。本文通过转录组数据,筛选到2个在干旱胁迫及复水处理下的差异基因ZmPP2C72(Zm00001d009626)和ZmPP2C97(Zm00001d025055),ZmPP2C72和ZmPP2C97基因分别位于玉米第8、10号染色体,具有高度保守的PP2C结构域。qRT-PCR结果显示,ZmPP2C72和ZmPP2C97在玉米各组织中均表达,属于组成型表达基因,ZmPP2C72在幼根中的表达量最高,而ZmPP2C97在成熟叶中表达量最高。在干旱、ABA及NaCl处理下,ZmPP2C72和ZmPP2C97基因都显著上调表达,说明ZmPP2C72和ZmPP2C97基因积极参与并响应非生物胁迫。ZmPP2C72和ZmPP2C97基因在干旱敏感型自交系B73及抗旱型自交系郑8713中表达量均显著上调,且ZmPP2C72基因的表达量比ZmPP2C97上调更显著。构建ZmPP2C72和ZmPP2C97基因的拟南芥过表达载体,对Col及纯合过表达株系进行干旱胁迫,测定叶绿素含量、丙二醛含量、SOD和POD活性,发现过表达ZmPP2C72和ZmPP2C97基因能够提高拟南芥植株的抗旱性。更多还原

【Abstract】 Drought seriously affects the yield and quality of maize, so mining drought-responsive genes and analyzing their genetic mechanisms are of great theoretical significance for breeding drought-resistant varieties. In this paper, we screened two differential genes, ZmPP2C72(Zm00001d009626) and ZmPP2C97(Zm00001d025055) under drought stress and rewatering treatments by using transcriptome data. ZmPP2C72 and ZmPP2C97 genes are located on maize chromosomes 8 and 10, and have a highly conserved PP2C structural domain. The q RT-PCR results showed that ZmPP2C72 and ZmPP2C97 were expressed in all tissues of maize and belonged to the constitutively expressed genes, with the highest expression of ZmPP2C72 in young roots and ZmPP2C97 in mature leaves. Both ZmPP2C72 and ZmPP2C97 genes were significantly up-regulated in expression under drought, ABA and Na Cl treatments, indicating that ZmPP2C72 and ZmPP2C97 genes actively participate in and respond to abiotic stresses. The expression of ZmPP2C72 and ZmPP2C97 genes was significantly up-regulated in the drought-sensitive inbred line B73 and the drought-resistant inbred line Zheng 8713, and the expression of ZmPP2C72 gene was more significantly up-regulated than that of ZmPP2C97. Arabidopsis overexpression vectors for ZmPP2C72 and ZmPP2C97 genes were constructed, and Col and pure overexpression lines were subjected to drought stress, and chlorophyll content, malondialdehyde content, SOD and POD activities were measured, and it was found that overexpression of ZmPP2C72 and ZmPP2C97 genes could improve drought tolerance of Arabidopsis plants.更多还原