N-myristoylation and S-acylation are common modifications of Ca2+-regulated Arabidopsis kinases and are required for activation of the SLAC1 anion channel

Shunya Saito, Shin Hamamoto, Koko Moriya, Aiko Matsuura, Yoko Sato, Jun Muto, Hiroto Noguchi, Seiji Yamauchi, Yuzuru Tozawa, Minoru Ueda, Kenji Hashimoto, Philipp Köster, Qiuyan Dong, Katrin Held, Jörg Kudla, Toshihiko Utsumi, Nobuyuki Uozumi

Research output: Contribution to journalArticlepeer-review

23 Citations (Scopus)

Abstract

N-myristoylation and S-acylation promote protein membrane association, allowing regulation of membrane proteins. However, how widespread this targeting mechanism is in plant signaling processes remains unknown. Through bioinformatics analyses, we determined that among plant protein kinase families, the occurrence of motifs indicative for dual lipidation by N-myristoylation and S-acylation is restricted to only five kinase families, including the Ca2+-regulated CDPK-SnRK and CBL protein families. We demonstrated N-myristoylation of CDPK-SnRKs and CBLs by incorporation of radiolabeled myristic acid. We focused on CPK6 and CBL5 as model cases and examined the impact of dual lipidation on their function by fluorescence microscopy, electrophysiology and functional complementation of Arabidopsis mutants. We found that both lipid modifications were required for proper targeting of CBL5 and CPK6 to the plasma membrane. Moreover, we identified CBL5–CIPK11 complexes as phosphorylating and activating the guard cell anion channel SLAC1. SLAC1 activation by CPK6 or CBL5–CIPK11 was strictly dependent on dual lipid modification, and loss of CPK6 lipid modification prevented functional complementation of cpk3 cpk6 guard cell mutant phenotypes. Our findings establish the general importance of dual lipid modification for Ca2+ signaling processes, and demonstrate their requirement for guard cell anion channel regulation.

Original languageEnglish
Pages (from-to)1504-1521
Number of pages18
JournalNew Phytologist
Volume218
Issue number4
DOIs
Publication statusPublished - 2018 Jun

Keywords

  • calcium
  • guard cell
  • ion channel
  • kinase
  • myristoylation
  • regulation

ASJC Scopus subject areas

  • Physiology
  • Plant Science

Fingerprint

Dive into the research topics of 'N-myristoylation and S-acylation are common modifications of Ca<sup>2+</sup>-regulated Arabidopsis kinases and are required for activation of the SLAC1 anion channel'. Together they form a unique fingerprint.

Cite this