Shi Xiao-Pu, Ren Jing-Jing, Qi Hao-Dong, Lin Yi, Wang Yu-Yi, Li De-Feng, Kong Lan-Jing, Wang Xiu-Ling
National Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, China.
Biology and Food Engineering School, Fuyang Normal University, Fuyang, China.
Front Plant Sci. 2021 Feb 4;12:622201. doi: 10.3389/fpls.2021.622201. eCollection 2021.
Abscisic acid (ABA) is an important phytohormone regulating plant growth, development and stress responses. A multitude of key factors implicated in ABA signaling have been identified; however, the regulation network of these factors needs for further information. AtS40.4, a plant-specific DUF584 domain-containing protein, was identified previously as a senescence regulator in . In this study, our finding showed that AtS40.4 was negatively involved in ABA signaling during seed germination and early seedling growth. was highly expressed in seeds and seedlings, and the expression level was promoted by ABA. AtS40.4 was localized both in the nucleus and the cytoplasm. Moreover, the subcellular localization pattern of AtS40.4 was affected by ABA. The knockdown mutants of exhibited an increased sensitivity to ABA, whereas the overexpression of decreased the ABA response during seed germination and seedling growth of . Furthermore, AtS40.4 was involved in ABRE-dependent ABA signaling and influenced the expression levels of () and . Further genetic evidence demonstrated that functioned upstream of These findings support the notion that AtS40.4 is a novel negative regulator of the ABA response network during seed germination and early seedling growth.
脱落酸（ABA）是一种重要的植物激素，可调节植物的生长、发育和应激反应。已经鉴定出许多参与ABA信号传导的关键因子；然而，这些因子的调控网络还需要更多信息。AtS40.4是一种植物特有的含DUF584结构域的蛋白质，先前在[具体内容缺失]中被鉴定为衰老调节因子。在本研究中，我们的发现表明AtS40.4在种子萌发和幼苗早期生长过程中对ABA信号传导起负调控作用。[具体内容缺失]在种子和幼苗中高表达，且其表达水平受ABA促进。AtS40.4定位于细胞核和细胞质中。此外，AtS40.4的亚细胞定位模式受ABA影响。[具体内容缺失]的敲除突变体对ABA的敏感性增加，而[具体内容缺失]的过表达则降低了[具体内容缺失]种子萌发和幼苗生长过程中的ABA反应。此外，AtS40.4参与依赖ABRE的ABA信号传导，并影响[具体内容缺失]（[具体基因缺失]）和[具体基因缺失]的表达水平。进一步的遗传学证据表明[具体内容缺失]在[具体基因缺失]的上游起作用。这些发现支持了AtS40.4是种子萌发和幼苗早期生长过程中ABA反应网络的新型负调控因子这一观点。
