D-2-hydroxyglutarate metabolism is linked to photorespiration in the shm1-1 mutant

Plant Biol (Stuttg). 2013 Jul;15(4):776-84. doi: 10.1111/plb.12020. Epub 2013 Apr 2.


The Arabidopsis mutant shm1-1 is defective in mitochondrial serine hydroxymethyltransferase 1 activity and displays a lethal photorespiratory phenotype at ambient CO2 concentration but grows normally at high CO2 . After transferring high CO2 -grown shm1-1 plants to ambient CO2 , the younger leaves remain photosynthetically active while developed leaves display increased yellowing and decreased FV /FM values. Metabolite analysis of plants transferred from high CO2 to ambient air indicates a massive light-dependent (photorespiratory) accumulation of glycine, 2-oxoglutarate (2OG) and D-2-hydroxyglutarate (D-2HG). Amino acid markers of senescence accumulated in ambient air in wild-type and shm1-1 plants maintained in darkness and also build up in shm1-1 in the light. This, together with an enhanced transcription of the senescence marker SAG12 in shm1-1, suggests the initiation of senescence in shm1-1 under photorespiratory conditions. Mitochondrial D-2HG dehydrogenase (D-2HGDH) converts D-2HG into 2OG. In vitro studies indicate that 2OG exerts competitive inhibition on D-2HGDH with a Ki of 1.96 mm. 2OG is therefore a suitable candidate as inhibitor of the in vivo D-2HGDH activity, as 2OG is produced and accumulates in mitochondria. Inhibition of the D-2HGDH by 2OG is likely a mechanism by which D-2HG accumulates in shm1-1, however it cannot be ruled out that D-2HG may also accumulate due to an active senescence programme that is initiated in these plants after transfer to photorespiratory conditions. Thus, a novel interaction of the photorespiratory pathway with cellular processes involving D-2HG has been identified.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / drug effects
  • Arabidopsis / genetics*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics*
  • Arabidopsis Proteins / metabolism
  • Carbon Dioxide / metabolism
  • Carbon Dioxide / pharmacology*
  • Cell Respiration
  • Cysteine Endopeptidases / genetics
  • Cysteine Endopeptidases / metabolism
  • Glutarates / analysis
  • Glutarates / metabolism*
  • Glycine / metabolism
  • Glycine Hydroxymethyltransferase / genetics*
  • Glycine Hydroxymethyltransferase / metabolism
  • Introns / genetics
  • Ketoglutaric Acids / metabolism
  • Light
  • Lysine / metabolism
  • Mitochondria / metabolism
  • Mutation
  • Phenotype
  • Photosynthesis
  • Plant Leaves / drug effects
  • Plant Leaves / genetics
  • Plant Leaves / metabolism
  • Plants, Genetically Modified
  • RNA Splice Sites / genetics
  • Recombinant Proteins


  • Arabidopsis Proteins
  • Glutarates
  • Ketoglutaric Acids
  • RNA Splice Sites
  • Recombinant Proteins
  • Carbon Dioxide
  • alpha-hydroxyglutarate
  • Glycine Hydroxymethyltransferase
  • SHM1 protein, Arabidopsis
  • SAG12 protein, Arabidopsis
  • Cysteine Endopeptidases
  • Lysine
  • Glycine