Yue Jie-Yu, Wang Ying-Jie, Jiao Jin-Lan, Wang Wen-Wen, Wang Hua-Zhong
Tianjin Key Laboratory of Animal and Plant Resistance, Tianjin Normal University, Tianjin, China.
Front Plant Sci. 2022 Jun 23;13:904933. doi: 10.3389/fpls.2022.904933. eCollection 2022.
Metacaspases (MCAs), a family of caspase-like proteins, are important regulators of programmed cell death (PCD) in plant defense response. Autophagy is an important regulator of PCD. This study explored the underlying mechanism of the interaction among PCD, MCAs, and autophagy and their impact on wheat response to salt stress. In this study, the wheat salt-responsive gene was identified. The open reading frame (ORF) of was 1,071 bp, coding 356 amino acids. The predicted molecular weight and isoelectric point were 38,337.03 Da and 8.45, respectively. had classic characteristics of type I MCAs domains, a typical N-terminal pro-domain rich in proline. was mainly localized in the chloroplast and exhibited nucleocytoplasmictrafficking under NaCl treatment. Increased expression of in wheat seedling roots and leaves was triggered by 150 mM NaCl treatment. Silencing of enhanced sensitivity of wheat seedlings to NaCl stress. Under NaCl stress, -silenced seedlings exhibited a reduction in activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), higher accumulation of HO and , more serious injury to photosystem II (PSII), increase in PCD level, and autophagy activity in leaves of wheat seedlings. These results indicated that functioned in PCD through interacting with autophagy under NaCl stress, which could be used to improve the salt tolerance of crop plants.
类半胱天冬酶（MCAs）是一类类半胱天冬酶蛋白，是植物防御反应中程序性细胞死亡（PCD）的重要调节因子。自噬是PCD的重要调节因子。本研究探讨了PCD、MCAs和自噬之间相互作用的潜在机制及其对小麦盐胁迫响应的影响。在本研究中，鉴定了小麦盐响应基因。该基因的开放阅读框（ORF）为1071 bp，编码356个氨基酸。预测的分子量和等电点分别为38337.03 Da和8.45。该基因具有I型MCAs结构域的经典特征，即典型的富含脯氨酸的N端前结构域。该基因主要定位于叶绿体，在NaCl处理下表现出核质运输。150 mM NaCl处理可诱导小麦幼苗根和叶中该基因表达增加。该基因沉默增强了小麦幼苗对NaCl胁迫的敏感性。在NaCl胁迫下，该基因沉默的幼苗超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）活性降低，H₂O₂和丙二醛积累增加，光系统II（PSII）损伤更严重，小麦幼苗叶片PCD水平和自噬活性增加。这些结果表明，该基因在NaCl胁迫下通过与自噬相互作用在PCD中发挥作用，可用于提高作物的耐盐性。
