Potential Regulatory Phosphorylation Sites in a Medicago Truncatula Plasma Membrane Proton Pump Implicated During Early Symbiotic Signaling in Roots

FEBS Lett. 2015 Aug 4;589(17):2186-93. doi: 10.1016/j.febslet.2015.06.035. Epub 2015 Jul 17.

Abstract

In plants and fungi the plasma membrane proton pump generates a large proton-motive force that performs essential functions in many processes, including solute transport and the control of cell elongation. Previous studies in yeast and higher plants have indicated that phosphorylation of an auto-inhibitory domain is involved in regulating pump activity. In this report we examine the Medicago truncatula plasma membrane proton pump gene family, and in particular MtAHA5. Yeast complementation assays with phosphomimetic mutations at six candidate sites support a phosphoregulatory role for two residues, suggesting a molecular model to explain early Nod factor-induced changes in the plasma membrane proton-motive force of legume root cells.

Keywords: Medicago truncatula; Nod factor; PM H(+)-ATPase; Phosphoproteomics; Phosphorylation; Proton pump.

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

  • Amino Acid Sequence
  • Binding Sites / genetics
  • Blotting, Western
  • Cell Membrane / enzymology*
  • Cluster Analysis
  • Gene Expression Regulation, Enzymologic
  • Genetic Complementation Test
  • Host-Pathogen Interactions
  • Medicago truncatula / enzymology*
  • Medicago truncatula / genetics
  • Medicago truncatula / microbiology
  • Molecular Sequence Data
  • Multigene Family
  • Mutation
  • Phosphorylation
  • Phylogeny
  • Plant Proteins / classification
  • Plant Proteins / genetics
  • Plant Proteins / metabolism*
  • Plant Roots / enzymology*
  • Plant Roots / genetics
  • Plant Roots / microbiology
  • Proton-Translocating ATPases / classification
  • Proton-Translocating ATPases / genetics
  • Proton-Translocating ATPases / metabolism*
  • Rhizobium / physiology
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae / growth & development
  • Sequence Homology, Amino Acid
  • Serine / genetics
  • Serine / metabolism
  • Signal Transduction
  • Symbiosis
  • Threonine / genetics
  • Threonine / metabolism

Substances

  • Plant Proteins
  • Threonine
  • Serine
  • Proton-Translocating ATPases