CALCIUM‐DEPENDENT PROTEIN KINASE32 regulates cellulose biosynthesis through post‐translational modification of cellulose synthase
CALCIUM‐DEPENDENT PROTEIN KINASE32 regulates cellulose biosynthesis through post‐translational modification of cellulose synthase
复制标题
钙依赖蛋白激酶32 通过纤维素合酶的翻译后修饰调节纤维素生物合成
DOI：
10.1111/nph.19106
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发表时间：
2023
期刊：
影响因子：
9.4
通讯作者：
Gu, Ying
中科院分区：
文献类型：
--
作者：
Xin, Xiaoran;Wei, Donghui;Lei, Lei;Zheng, Haiyan;Wallace, Ian S.;Li, Shundai;Gu, Ying
纤维素是植物细胞壁的重要组成部分，也是食品、纸张、纺织品和生物燃料的重要经济来源。尽管其经济和生物学意义，纤维素生物合成的调控知之甚少。纤维素酶（CESA）的磷酸化和去磷酸化被证明影响纤维素合成酶复合物（CSC）的方向和速度。然而，磷酸化CESA的蛋白激酶在很大程度上是未知的。我们在拟南芥中进行了研究，以揭示磷酸化CESA的蛋白激酶。在这项研究中，我们使用酵母双杂交，蛋白生物化学，遗传学和活细胞成像来揭示钙依赖性蛋白激酶32（CPK32）在拟南芥纤维素生物合成调控中的作用。我们在酵母双杂交试验中使用CESA 3作为诱饵来鉴定CPK32。我们发现CPK32磷酸化CESA3，同时与CESA1和CESA3相互作用。过度表达功能缺陷的CPK32变体和CESA3的磷酸化死亡突变导致CSC的运动性降低和黄化幼苗中结晶纤维素含量降低。我们发现了CPKs调节纤维素生物合成的新功能和磷酸化调节CSCs稳定性的新机制。
Cellulose is an essential component of plant cell walls and an economically important source of food, paper, textiles, and biofuel. Despite its economic and biological significance, the regulation of cellulose biosynthesis is poorly understood. Phosphorylation and dephosphorylation of cellulose synthases (CESAs) were shown to impact the direction and velocity of cellulose synthase complexes (CSCs). However, the protein kinases that phosphorylate CESAs are largely unknown. We conducted research inArabidopsis thalianato reveal protein kinases that phosphorylate CESAs.In this study, we used yeast two‐hybrid, protein biochemistry, genetics, and live‐cell imaging to reveal the role of calcium‐dependent protein kinase32 (CPK32) in the regulation of cellulose biosynthesis inA. thaliana.We identified CPK32 using CESA3 as a bait in a yeast two‐hybrid assay. We showed that CPK32 phosphorylates CESA3 while it interacts with both CESA1 and CESA3. Overexpressing functionally defective CPK32 variant and phospho‐dead mutation of CESA3 led to decreased motility of CSCs and reduced crystalline cellulose content in etiolated seedlings. Deregulation of CPKs impacted the stability of CSCs.We uncovered a new function of CPKs that regulates cellulose biosynthesis and a novel mechanism by which phosphorylation regulates the stability of CSCs.