Abstract：
Seed germination is a critical checkpoint for plant growth under unfavorable environmental conditions. In Arabidopsis (Arabidopsis thaliana), the abscisic acid (ABA) and gibberellic acid (GA) signaling pathways play important roles in modulating seed germination. However, the molecular links between salinity stress and ABA/GA signaling are not well understood. Herein, we showed that the expression of DIVARICATA1 (DIV1), which encodes a MYB-like transcription factor, was induced by GA and repressed by ABA, salinity, and osmotic stress in germinating seeds. DIV1 positively regulated seed germination in response to salinity stress by directly regulating the expression of DELAY OF GERMINATION 1-LIKE 3 (DOGL3) and GA-STIMULATED ARABIDOPSIS 4 (GASA4) and indirectly regulating the expression of several germination-associated genes. Moreover, NUCLEAR FACTOR-YC9 (NF-YC9) directly repressed the expression of DIV1 in germinating seeds in response to salinity stress. These results help reveal the function of the NF-YC9-DIV1 module and provide insights into the regulation of ABA and GA signaling in response to salinity stress during seed germination in Arabidopsis.
摘要：
种子萌发是不利环境条件下植物生长的关键关卡。在拟南芥（拟南芥）中，脱落酸（ABA）和赤霉酸（GA）信号通路在调控种子萌发中起着重要作用。然而,盐度胁迫和ABA/GA信号之间的分子联系还没有很好的理解。在这里，我们显示DIVARICATA1（DIV1）的表达，编码MYB样转录因子,由GA诱导并由ABA抑制，盐度,和发芽种子的渗透胁迫。DIV1通过直接调节发芽延迟1-like3（DOGL3）和GA刺激的ARABIDOPSIS4（GASA4）的表达，并间接调节几种发芽相关基因的表达，从而正向调节种子发芽以响应盐度胁迫。此外，核因子-YC9（NF-YC9）直接抑制了发芽种子中DIV1的表达，以应对盐度胁迫。这些结果有助于揭示NF-YC9-DIV1模块的功能，并提供对拟南芥种子萌发过程中响应盐度胁迫的ABA和GA信号调节的见解。
