Down-regulation of PvTRE1 enhances nodule biomass and bacteroid number in the common bean

New Phytol. 2013 Jan;197(1):194-206. doi: 10.1111/nph.12002. Epub 2012 Nov 1.

Abstract

Legume-rhizobium interactions have been widely studied and characterized, and the disaccharide trehalose has been commonly detected during this symbiotic interaction. It has been proposed that trehalose content in nodules during this symbiotic interaction might be regulated by trehalase. In the present study, we assessed the role of trehalose accumulation by down-regulating trehalase in the nodules of common bean plants. We performed gene expression analysis for trehalase (PvTRE1) during nodule development. PvTRE1 was knocked down by RNA interference (RNAi) in transgenic nodules of the common bean. PvTRE1 expression in nodulated roots is mainly restricted to nodules. Down-regulation of PvTRE1 led to increased trehalose content (78%) and bacteroid number (almost one order of magnitude). In addition, nodule biomass, nitrogenase activity, and GOGAT transcript accumulation were significantly enhanced too. The trehalose accumulation, triggered by PvTRE1 down-regulation, led to a positive impact on the legume-rhizobium symbiotic interaction. This could contribute to the agronomical enhancement of symbiotic nitrogen fixation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agrobacterium / genetics
  • Agrobacterium / metabolism
  • Autophagy
  • Bacterial Load
  • Carbohydrate Metabolism
  • Cloning, Molecular
  • Escherichia coli / enzymology
  • Escherichia coli / genetics
  • Gene Expression Regulation, Enzymologic
  • Gene Expression Regulation, Plant
  • Gene Knockdown Techniques
  • Genes, Plant
  • Microbial Viability
  • Nitrogen Fixation
  • Nitrogenase / genetics
  • Nitrogenase / metabolism
  • Phaseolus / enzymology
  • Phaseolus / genetics
  • Phaseolus / microbiology*
  • Phylogeny
  • Plant Leaves / enzymology
  • Plant Leaves / genetics
  • Plant Root Nodulation
  • Plants, Genetically Modified / enzymology
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / microbiology
  • Promoter Regions, Genetic
  • RNA Interference
  • Rhizobium etli / growth & development*
  • Rhizobium etli / isolation & purification
  • Rhizobium etli / metabolism
  • Root Nodules, Plant / enzymology*
  • Root Nodules, Plant / microbiology
  • Symbiosis*
  • Transformation, Genetic
  • Trehalase / genetics
  • Trehalase / metabolism*
  • Trehalose / metabolism*

Substances

  • Trehalose
  • Nitrogenase
  • Trehalase