CPK1通过磷酸化激活环核苷酸门控离子通道（CNGCs），以实现钙信号传导，从而促进拟南芥根毛生长。

CPK1 activates CNGCs through phosphorylation for Ca signaling to promote root hair growth in Arabidopsis.

作者信息

Zhu Meijun, Du Bo-Ya, Tan Yan-Qiu, Yang Yang, Zhang Yang, Wang Yong-Fei

机构信息

State Key Laboratory of Plant Trait Design, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences (CAS), Shanghai, 200032, China.

University of Chinese Academy of Sciences, Shanghai, 200032, China.

出版信息

Nat Commun. 2025 Jan 15;16(1):676. doi: 10.1038/s41467-025-56008-4.

DOI:10.1038/s41467-025-56008-4

PMID:39809784

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11733299/

Abstract

Cyclic nucleotide-gated channel 5 (CNGC5), CNGC6, and CNGC9 (CNGC5/6/9 for simplicity) control Arabidopsis root hair (RH) growth by mediating the influx of external Ca to establish and maintain a sharp cytosolic Ca gradient at RH tips. However, the underlying mechanisms for the regulation of CNGCs remain unknown. We report here that calcium dependent protein kinase 1 (CPK1) directly activates CNGC5/6/9 to promote Arabidopsis RH growth. The loss-of-function mutants cpk1-1, cpk1-2, cngc5-1 cngc6-2 cngc9-1 (shrh1/short root hair 1), and cpk1 shrh1 show similar RH phenotypes, including shorter RHs, more RH branching, and dramatically attenuated cytosolic Ca gradients at RH tips. The main CPK1-target sites are identified as Ser20, Ser27, and Ser26 for CNGC5/6/9, respectively, and the corresponding alanine substitution mutants fail to rescue RH growth in shrh1 and cpk1-1, while phospho-mimic versions restore the cytosolic Ca gradient at RH apex and rescue the RH phenotypes in the same Arabidopsis mutants. Thus we discover the CPK1-CNGC modules essential for the Ca signaling regulation and RH growth in Arabidopsis.

摘要

环核苷酸门控通道5（CNGC5）、CNGC6和CNGC9（为简便起见简称为CNGC5/6/9）通过介导外部钙离子内流来控制拟南芥根毛（RH）的生长，从而在根毛顶端建立并维持一个陡峭的胞质钙离子梯度。然而，CNGCs调控的潜在机制仍不清楚。我们在此报告，钙依赖蛋白激酶1（CPK1）直接激活CNGC5/6/9以促进拟南芥根毛生长。功能缺失突变体cpk1-1、cpk1-2、cngc5-1 cngc6-2 cngc9-1（shrh1/短根毛1）和cpk1 shrh1表现出相似的根毛表型，包括较短的根毛、更多的根毛分支以及根毛顶端胞质钙离子梯度显著减弱。已确定CPK1的主要作用位点分别为CNGC5/6/9的Ser20、Ser27和Ser26，相应的丙氨酸替代突变体无法拯救shrh1和cpk1-1中的根毛生长，而磷酸化模拟版本则恢复了根毛顶端的胞质钙离子梯度，并拯救了相同拟南芥突变体中的根毛表型。因此，我们发现了拟南芥中钙信号调控和根毛生长所必需的CPK1-CNGC模块。