植物CDPK在响应逆境胁迫中的作用及机制

Functions and mechanisms of CDPKs in plant responses to abiotic stress

摘要:

钙依赖性蛋白激酶(calcium-dependent protein kinase,CDPK/CPK)是一类Ca²⁺敏感的Ser/Thr蛋白激酶，在植物生长发育和逆境胁迫响应中发挥重要作用。CDPK能够迅速感知细胞内瞬时Ca²⁺信号的变化，识别并磷酸化特异性底物，从而将Ca²⁺信号向下游传递并级联放大，广泛参与干旱、盐碱和伤害应激等逆境胁迫，调控植物生长发育以及相关基因表达、离子通道和气孔运动等。CDPK的自磷酸化会影响其酶活性以及底物的选择性。CDPK具有与多种底物结合并磷酸化的能力，除了参与呼吸暴发氧化酶同源物(respiratory burst oxidase homolog,RBOH)、丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)、植物激素等信号通路，CDPK还可以与14-3-3蛋白结合，调控植物应对逆境胁迫和促进生长发育。本研究综述了植物CDPK的发现、结构、分类及其在逆境胁迫响应中的作用等方面的研究成果，并对其未来研究方向进行展望，为农作物抗逆性遗传改良提供了基因资源和理论依据。

Abstract:

Calcium-dependent protein kinases (CDPKs/CPKs) are members of the Ca²⁺-sensitive Ser/Thr protein kinase family and play a crucial role in plant growth and development and responses to abiotic stress. CDPKs are capable of rapidly sensing changes in intracellular Ca²⁺ signals and recognizing and phosphorylating specific substrates, thereby transmitting and amplifying Ca²⁺ signal cascades downstream. They are involved in plant responses to stress conditions such as drought, saline-alkali stress, and injuries and regulate plant growth and development, gene expression, ion channel activity, and stomatal movement. The autophosphorylation of CDPKs can affect their activities and substrate specificity. CDPKs have the ability to bind to and phosphorylate multiple substrates. In addition to participating in respiratory burst oxidase homolog (RBOH), mitogen-activated protein kinase (MAPK), and plant hormone signaling pathways, CDPKs can also bind to 14-3-3 proteins, which enables the regulation of plant responses to stress and promotes plant growth and development. This paper summarized the research findings on the discovery, structure, classification, and roles of CDPKs in plant responses to stress and proposed the future research directions, aiming to provide the genetic resources and a theoretical basis for improving the stress tolerance of crops.