State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, 100193 Beijing, China.
State Key Laboratory of Plant Environmental Resilience, College of Biological Sciences, China Agricultural University, 100193 Beijing, China; Center for Crop Functional Genomics and Molecular Breeding, China Agricultural University, Beijing 100193, China.
Plant Sci. 2023 Sep;334:111774. doi: 10.1016/j.plantsci.2023.111774. Epub 2023 Jun 16.
Leaf senescence is an integral step in the final stages of plant development, as nutrient remobilization from leaves to sink organs is accomplished during this process. NACs compose a large superfamily of plant-specific TFs involved in multiple plant development processes. Here, we identified a maize NAC TF, ZmNAC132, involved in leaf senescence and male fertility. ZmNAC132 expression was tightly linked to leaf senescence in an age-dependent manner. Knockout of ZmNAC132 led to delays in chlorophyll degradation and leaf senescence, whereas overexpression of ZmNAC132 had the opposite effects. ZmNAC132 could bind to and transactivate the promoter of ZmNYE1, a major chlorophyll catabolic gene, to accelerate chlorophyll degradation during leaf senescence. Moreover, ZmNAC132 affected male fertility through the upregulation of ZmEXPB1, an expansin-encoding gene associated with sexual reproduction and other related genes. Together, the results show that ZmNAC132 participates in the regulation of leaf senescence and male fertility through the targeting of different downstream genes in maize.
叶片衰老是植物发育末期的一个重要步骤，因为在此过程中，营养物质从叶片向汇器官重新分配。NAC 组成了一个庞大的植物特异性 TF 超家族，参与了多种植物发育过程。在这里，我们鉴定了一个参与叶片衰老和雄性育性的玉米 NAC TF，ZmNAC132。ZmNAC132 的表达与叶片衰老呈年龄依赖性紧密相关。ZmNAC132 的敲除导致叶绿素降解和叶片衰老延迟，而过表达则产生相反的效果。ZmNAC132 可以结合并激活主要的叶绿素降解基因 ZmNYE1 的启动子，从而加速叶片衰老过程中的叶绿素降解。此外，ZmNAC132 通过上调与有性生殖和其他相关基因相关的扩展蛋白编码基因 ZmEXPB1 影响雄性育性。总之，这些结果表明，ZmNAC132 通过靶向玉米中的不同下游基因参与叶片衰老和雄性育性的调节。
