College of Grassland Science and Technology, Sichuan Agricultural University, Chengdu 611130, China.
Institute of Agricultural Resources and Environment, Sichuan Academy of Agricultural Sciences, Chengdu 610066, China.
Int J Mol Sci. 2023 Oct 18;24(20):15280. doi: 10.3390/ijms242015280.
is one of the world-famous forage grasses with rich biomass, fast growth rate and good nutritional quality. However, its growth and forage yield are often affected by drought, which is a major natural disaster all over the world. MYB transcription factors have some specific roles in response to drought stress, such as regulation of stomatal development and density, control of cell wall and root development. However, the biological function of MYB in remains unclear. Previously, we elucidated the role of in enhancing osmotic stress resistance in . Here, this study elucidates the biological function of in enhancing plant drought tolerance through an ABA-dependent pathway involving the regulation of cell wall development and stomatal density. After drought stress and ABA stress, the expression of in was significantly increased. Overexpression of increased the survival rate of under drought stress. Under drought conditions, expression levels of drought-responsive genes such as and were up-regulated in OE compared with those in WT. Further observation showed that the stomatal density of OE was reduced, which was associated with the up-regulated expression of cell wall-related pathway genes in the RNA-Seq results. In conclusion, this study confirmed the biological function of 1 in improving drought tolerance by mediating cell wall development through the ABA-dependent pathway and thereby affecting stomatal density.
是世界著名的饲用牧草之一,具有生物量大、生长速度快、营养品质好等特点。然而,其生长和饲用产量常受到干旱的影响,干旱是世界各地的主要自然灾害。MYB 转录因子在响应干旱胁迫方面具有一些特定的作用,例如调节气孔的发育和密度、控制细胞壁和根系的发育。然而,在 中的 MYB 的生物学功能尚不清楚。之前,我们阐明了 在提高 中的渗透胁迫抗性方面的作用。在这里,本研究通过涉及细胞壁发育和气孔密度调节的 ABA 依赖途径,阐明了 在增强植物抗旱性方面的生物学功能。在干旱胁迫和 ABA 胁迫后, 在 中的表达显著增加。过表达 增加了干旱胁迫下 的存活率。在干旱条件下,与 WT 相比,OE 中干旱响应基因如 和 的表达水平上调。进一步观察表明,OE 的气孔密度降低,这与 RNA-Seq 结果中细胞壁相关途径基因的上调表达有关。总之,本研究通过 ABA 依赖途径介导细胞壁发育证实了 1 提高耐旱性的生物学功能,从而影响气孔密度。