Valmonte-Cortes Gardette R, Higgins Colleen M, MacDiarmid Robin M
School of Science, AUT City Campus, Auckland University of Technology, Auckland 1142, New Zealand.
The New Zealand Institute for Plant & Food Research Limited, 120 Mt Albert Road, Auckland 1025, New Zealand.
Plants (Basel). 2025 Jan 20;14(2):294. doi: 10.3390/plants14020294.
Calcium-dependent protein kinases (CPKs) are plant proteins that directly bind calcium ions before phosphorylating substrates involved in biotic and abiotic stress responses, as well as development. CPK3 () is involved with plant signaling pathways such as stomatal movement regulation, salt stress response, apoptosis, seed germination and pathogen defense. In this study, and its orthologues in relatively distant plant species such as rice (, monocot) and kiwifruit (, asterid eudicot) were analyzed in response to drought, bacteria, fungi, and virus infections. Two orthologues were studied in , namely and , while one orthologue--was identified in . Reverse-transcriptase quantitative PCR (RT-qPCR) analysis revealed that and exhibit similar responses to stressors to . responded differently, particularly in bacterial and fungal infections. An increase in expression was consistently observed among and its orthologues in response to virus infection. Overexpression mutants in both Arabidopsis and kiwifruit showed slight tolerance to drought, while knockout mutants were slightly more susceptible or had little difference with wild-type plants. Overexpression mutants in Arabidopsis showed slight tolerance to virus infection. These findings highlight the importance of and its orthologues in drought and pathogen responses and suggest such function must be conserved in its orthologues in a wide range of plants.
钙依赖性蛋白激酶（CPKs）是一类植物蛋白，在磷酸化参与生物和非生物胁迫反应以及发育过程的底物之前，它们会直接结合钙离子。CPK3（ ）参与植物信号传导途径，如气孔运动调节、盐胁迫反应、细胞凋亡、种子萌发和病原体防御。在本研究中，对其以及在水稻（ ，单子叶植物）和猕猴桃（ ，菊亚纲真双子叶植物）等亲缘关系较远的植物物种中的直系同源物进行了干旱、细菌、真菌和病毒感染方面的分析。在拟南芥中研究了两个直系同源物，即 和 ，而在猕猴桃中鉴定出了一个直系同源物—— 。逆转录定量PCR（RT-qPCR）分析表明， 和 对胁迫源的反应与 相似。 的反应有所不同，特别是在细菌和真菌感染方面。在 及其直系同源物中，病毒感染后均持续观察到表达增加。拟南芥和猕猴桃中的过表达突变体对干旱表现出轻微耐受性，而敲除突变体则稍更易感或与野生型植物无明显差异。拟南芥中的过表达突变体对病毒感染表现出轻微耐受性。这些发现突出了 及其直系同源物在干旱和病原体反应中的重要性，并表明这种功能在广泛植物的直系同源物中必定是保守的。
