School of Life Sciences, Qufu Normal University, Qufu, 273165, China.
Plant Cell Rep. 2024 Sep 28;43(10):244. doi: 10.1007/s00299-024-03335-3.
Overexpression of ZmNAC19, a NAC transcription factor gene from maize, improves embryo development in transgenic Arabidopsis. NAC proteins are plant-specific transcription factors that are involved in multiple aspects of plant growth, development and stress response. Although functions of many NAC transcription factors have been elucidated, little is known about their roles in seed development. In this study, we report the function of a maize NAC transcription factor ZmNAC19 in seed development. ZmNAC19 is highly expressed in embryos of developing maize seeds. ZmNAC19 localizes to nucleus and exhibits transactivation activity in yeast cells. Overexpression of ZmNAC19 in Arabidopsis significantly increases seed size and seed yield. During 3 to 7 days after flowering, embryos of ZmNAC19-overexpression Arabidopsis lines developed faster compared to Col-0, while no visible differences were detected for their endosperms. Furthermore, overexpression of ZmNAC19 in Arabidopsis leads to increased transcription levels of two embryo development-related genes YUC1 and RGE1, and several elements proven to be binding sites of NAC transcription factors were observed in promoters of these two genes. Taken together, these results suggest that ZmNAC19 acts as a positive regulator in plant embryo development.
ZmNAC19 是玉米中的一个 NAC 转录因子基因，其过表达可改善转基因拟南芥中的胚胎发育。NAC 蛋白是植物特异性转录因子，参与植物生长、发育和应激反应的多个方面。尽管许多 NAC 转录因子的功能已经阐明，但它们在种子发育中的作用知之甚少。在这项研究中，我们报告了玉米 NAC 转录因子 ZmNAC19 在种子发育中的功能。ZmNAC19 在发育中的玉米种子胚胎中高度表达。ZmNAC19 定位于细胞核，并在酵母细胞中表现出转录激活活性。在拟南芥中过表达 ZmNAC19 可显著增加种子大小和产量。在开花后 3 至 7 天，ZmNAC19 过表达拟南芥系的胚胎发育速度比 Col-0 更快，而它们的胚乳没有明显差异。此外，在拟南芥中过表达 ZmNAC19 导致两个胚胎发育相关基因 YUC1 和 RGE1 的转录水平升高，并且在这两个基因的启动子中观察到几个被证明是 NAC 转录因子结合位点的元件。综上所述，这些结果表明 ZmNAC19 作为植物胚胎发育的正调控因子发挥作用。
