A G protein-coupled receptor-like module regulates cellulose synthase secretion from the endomembrane system in Arabidopsis

Dev Cell. 2021 May 17;56(10):1484-1497.e7. doi: 10.1016/j.devcel.2021.03.031. Epub 2021 Apr 19.

Abstract

Cellulose is produced at the plasma membrane of plant cells by cellulose synthase (CESA) complexes (CSCs). CSCs are assembled in the endomembrane system and then trafficked to the plasma membrane. Because CESAs are only active in the plasma membrane, control of CSC secretion regulates cellulose synthesis. We identified members of a family of seven transmembrane domain-containing proteins (7TMs) that are important for cellulose production during cell wall integrity stress. 7TMs are often associated with guanine nucleotide-binding (G) protein signaling and we found that mutants affecting the Gβγ dimer phenocopied the 7tm mutants. Unexpectedly, the 7TMs localized to the Golgi/trans-Golgi network where they interacted with G protein components. Here, the 7TMs and Gβγ regulated CESA trafficking but did not affect general protein secretion. Our results outline how a G protein-coupled module regulates CESA trafficking and reveal that defects in this process lead to exacerbated responses to cell wall integrity stress.

Keywords: G protein-coupled receptor; GPCR; cell wall signaling; cellulose; cellulose synthesis; plant cell biology; plant cell walls; secretion.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / metabolism*
  • Cell Membrane / metabolism*
  • Cell Wall / metabolism
  • GTP-Binding Proteins / genetics
  • GTP-Binding Proteins / metabolism
  • Glucosyltransferases / metabolism*
  • Membrane Proteins / metabolism
  • Multiprotein Complexes / metabolism
  • Mutation / genetics
  • Protein Binding
  • Receptors, G-Protein-Coupled / metabolism*
  • Seedlings / growth & development
  • Seedlings / ultrastructure
  • Signal Transduction
  • Stress, Physiological
  • trans-Golgi Network / metabolism
  • trans-Golgi Network / ultrastructure

Substances

  • Arabidopsis Proteins
  • Membrane Proteins
  • Multiprotein Complexes
  • Receptors, G-Protein-Coupled
  • Glucosyltransferases
  • cellulose synthase
  • GTP-Binding Proteins