Zhang Yuanyuan, Li Qi, Jiang Mengyang, Tian Hui, Khalid Muhammad Hayder Bin, Wang Yingge, Yu Haoqiang
Ecological Security and Protection Key Laboratory of Sichuan Province, College of Life Science & Biotechnology, Mianyang Normal University, Mianyang 621000, China.
Maize Research Institute, Sichuan Agricultural University, Chengdu 611130, China.
Plants (Basel). 2024 Sep 7;13(17):2512. doi: 10.3390/plants13172512.
Drought stress is a primary abiotic stress that causes significant losses to forestry and agricultural production. Therefore, exploring drought-responsive genes and their regulatory mechanism is crucial for plant molecular breeding for forestry and agriculture production safety. Small auxin-up RNA (SAUR) proteins are essential in plant growth and development but show functional diversity in stress response. In this study, the transcriptome sequencing data of seedlings revealed that the expression of was continuously downregulated under drought stress. Hence, the gene was cloned and functionally analyzed in drought response. The results showed that the coding sequence of was 315 bp in length and encoded 104 amino acids. The AnSAUR50 protein showed high conservation, possessed a SAUR-specific domain, and localized in the nucleus and cell membrane. The heterologous expression of the AnSAUR50 gene enhanced the drought sensitivity of the transgenic Arabidopsis with a lower survival rate, biomass, and higher malondialdehyde content and relative electrolyte leakage. Moreover, transgenic plants showed shorter root lengths and bigger stomatal apertures, resulting in facilitating water loss under drought stress. The study indicates that negatively regulates drought tolerance by inhibiting root growth and stomatal closure, which provides insights into the underlying function and regulatory mechanism of SAURs in plant stress response.
干旱胁迫是一种主要的非生物胁迫，会给林业和农业生产造成重大损失。因此，探索干旱响应基因及其调控机制对于保障林业和农业生产安全的植物分子育种至关重要。小生长素上调RNA（SAUR）蛋白在植物生长发育中必不可少，但在胁迫响应中表现出功能多样性。在本研究中，幼苗的转录组测序数据显示，在干旱胁迫下， 的表达持续下调。因此，克隆了 基因并对其在干旱响应中的功能进行了分析。结果表明， 的编码序列长度为315 bp，编码104个氨基酸。AnSAUR50蛋白具有高度保守性，拥有一个SAUR特异性结构域，定位于细胞核和细胞膜。AnSAUR50基因的异源表达增强了转基因拟南芥的干旱敏感性，其存活率、生物量较低，丙二醛含量和相对电解质渗漏率较高。此外，转基因植物的根较短，气孔孔径较大，导致在干旱胁迫下水分流失加剧。该研究表明， 通过抑制根生长和气孔关闭对耐旱性起负调控作用，这为深入了解SAURs在植物胁迫响应中的潜在功能和调控机制提供了思路。
