2023-07-11 ペンシルベニア州立大学(PennState)
◆植物細胞壁の重要な構成要素であるセルロースの生成がどのように制御されているかは明らかにされていなかった。
◆ペンシルバニア州立大学の研究者らが率いるチームが、セルロースを生成する細胞内機械の安定性を与えるために責任を持つ細胞内機械を修正するタンパク質を同定した。
◆この新しい理解は、バイオ燃料やその他の用途のためにより安定したセルロース豊富な材料の設計に役立つ可能性がある。
<関連情報>
- https://www.psu.edu/news/eberly-college-science/story/newly-identified-protein-regulates-creation-cellulose-plant-cells/
- https://nph.onlinelibrary.wiley.com/doi/10.1111/nph.19106
セルロース合成酵素の翻訳後修飾を通じてセルロース生合成を制御するCALCIUM-DEPENDENT PROTEIN KINASE32 CALCIUM-DEPENDENT PROTEIN KINASE32 regulates cellulose biosynthesis through post-translational modification of cellulose synthase
Xiaoran Xin, Donghui Wei, Lei Lei, Haiyan Zheng, Ian S. Wallace, Shundai Li, Ying Gu
New Phytologist Published: 10 July 2023
DOI:https://doi.org/10.1111/nph.19106
Summary
- 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 in Arabidopsis thaliana to 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 in A. 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.
