CRK2 Enhances Salt Tolerance by Regulating Callose Deposition in Connection with PLD α 1

Plant Physiol. 2019 Aug;180(4):2004-2021. doi: 10.1104/pp.19.00560. Epub 2019 May 22.

Abstract

High salinity is an increasingly prevalent source of stress to which plants must adapt. The receptor-like protein kinases, including members of the Cys-rich receptor-like kinase (CRK) subfamily, are a highly expanded family of transmembrane proteins in plants that are largely responsible for communication between cells and the extracellular environment. Various CRKs have been implicated in biotic and abiotic stress responses; however, their functions on a cellular level remain largely uncharacterized. Here we have shown that CRK2 enhances salt tolerance at the germination stage in Arabidopsis (Arabidopsis thaliana) and also modulates root length. We established that functional CRK2 is required for salt-induced callose deposition. In doing so, we revealed a role for callose deposition in response to increased salinity and demonstrated its importance for salt tolerance during germination. Using fluorescently tagged proteins, we observed specific changes in the subcellular localization of CRK2 in response to various stress treatments. Many of CRK2's cellular functions were dependent on phospholipase D activity, as were the subcellular localization changes. Thus, we propose that CRK2 acts downstream of phospholipase D during salt stress, promoting callose deposition and regulating plasmodesmal permeability, and that CRK2 adopts specific stress-dependent subcellular localization patterns that allow it to carry out its functions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / drug effects
  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Gene Expression Regulation, Plant / genetics
  • Gene Expression Regulation, Plant / physiology
  • Germination / drug effects
  • Plants, Genetically Modified / drug effects
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / metabolism
  • Salt Tolerance
  • Stress, Physiological / genetics
  • Stress, Physiological / physiology

Substances

  • Arabidopsis Proteins