Functions of Calcium-Dependent Protein Kinases in Plant Innate Immunity.
Functions of Calcium-Dependent Protein Kinases in Plant Innate Immunity.
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DOI：
10.3390/plants3010160
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发表时间：
2014-03-05
期刊：
影响因子：
--
通讯作者：
He P
中科院分区：
文献类型：
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作者：
Gao X;Cox KL Jr;He P
细胞质 Ca2+ 的增加是由多种生理刺激和应激（包括病原体攻击）引起的。植物进化出了免疫系统的两个分支来防御病原体感染。初级先天免疫反应是通过检测进化上保守的病原体相关分子模式（PAMP）而触发的，这被称为PAMP触发免疫（PTI）。植物先天免疫的第二个分支是由特定病原体效应蛋白的识别触发的，称为效应触发免疫（ETI）。钙 (Ca2+) 信号传导在植物 PTI 和 ETI 反应中都至关重要。钙依赖性蛋白激酶 (CDPK) 已成为重要的 Ca2+ 传感器蛋白，可通过 PAMP 或效应器触发并激活复杂的下游反应，转导差异化 Ca2+ 特征。 CDPK 通过钙与 C 末端的延伸因子 (EF) 手结构域结合以及 N 末端的催化激酶结构域的底物磷酸化来直接传递钙信号。新出现的证据表明，特异性和重叠的 CDPK 磷酸化 PTI 和 ETI 中的不同底物，以调节不同的植物免疫反应，包括活性氧的产生、免疫基因的转录重编程和过敏反应。
An increase of cytosolic Ca2+ is generated by diverse physiological stimuli and stresses, including pathogen attack. Plants have evolved two branches of the immune system to defend against pathogen infections. The primary innate immune response is triggered by the detection of evolutionarily conserved pathogen-associated molecular pattern (PAMP), which is called PAMP-triggered immunity (PTI). The second branch of plant innate immunity is triggered by the recognition of specific pathogen effector proteins and known as effector-triggered immunity (ETI). Calcium (Ca2+) signaling is essential in both plant PTI and ETI responses. Calcium-dependent protein kinases (CDPKs) have emerged as important Ca2+ sensor proteins in transducing differential Ca2+ signatures, triggered by PAMPs or effectors and activating complex downstream responses. CDPKs directly transmit calcium signals by calcium binding to the elongation factor (EF)-hand domain at the C-terminus and substrate phosphorylation by the catalytic kinase domain at the N-terminus. Emerging evidence suggests that specific and overlapping CDPKs phosphorylate distinct substrates in PTI and ETI to regulate diverse plant immune responses, including production of reactive oxygen species, transcriptional reprogramming of immune genes, and the hypersensitive response.