Requirement of vesicle-associated membrane protein 721 and 722 for sustained growth during immune responses in Arabidopsis

Mol Cells. 2013 Jun;35(6):481-8. doi: 10.1007/s10059-013-2130-2. Epub 2013 May 8.


Extracellular immune responses to ascomycete and oomycete pathogens in Arabidopsis are dependent on vesicle-associated secretion mediated by the SNARE proteins PEN1 syntaxin, SNAP33 and endomembrane-resident VAMP721/722. Continuous movement of functional GFP-VAMP722 to and from the plasma membrane in non-stimulated cells reflects the second proposed function of VAMP721/722 in constitutive secretion during plant growth and development. Application of the bacterium-derived elicitor flg22 stabilizes VAMP721/722 that are otherwise constitutively degraded via the 26S proteasome pathway. Depletion of VAMP721/722 levels by reducing VAMP721/722 gene dosage enhances flg22-induced seedling growth inhibition in spite of elevated VAMP721/722 abundance. We therefore propose that plants prioritize the deployment of the corresponding secretory pathway for defense over plant growth. Interstingly, VAMP721/722 specifically interact in vitro and in vivo with the plasma membrane syntaxin SYP132 that is required for plant growth and resistance to bacteria. This suggests that the plant growth/immunity-involved VAMP721/722 form SNARE complexes with multiple plasma membrane syntaxins to discharge cue-dependent cargo molecules.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / immunology*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / immunology
  • Arabidopsis Proteins / metabolism*
  • Cell Growth Processes / genetics
  • Cell Growth Processes / immunology
  • Cell Membrane / metabolism*
  • Cells, Cultured
  • Gene Dosage / genetics
  • Immunity / genetics
  • Proteasome Endopeptidase Complex / metabolism
  • Protein Transport / genetics
  • Protein Transport / immunology
  • Qa-SNARE Proteins / metabolism*
  • Qb-SNARE Proteins / metabolism
  • Qc-SNARE Proteins / metabolism
  • R-SNARE Proteins / genetics
  • R-SNARE Proteins / immunology
  • R-SNARE Proteins / metabolism*
  • Seedlings / genetics


  • Arabidopsis Proteins
  • PEN1 protein, Arabidopsis
  • Qa-SNARE Proteins
  • Qb-SNARE Proteins
  • Qc-SNARE Proteins
  • R-SNARE Proteins
  • SNAP33 protein, Arabidopsis
  • SYP132 protein, Arabidopsis
  • VAMP721 protein, Arabidopsis
  • VAMP722 protein, Arabidopsis
  • Proteasome Endopeptidase Complex
  • ATP dependent 26S protease