The mitochondrial LYR protein SDHAF1 is required for succinate dehydrogenase activity in Arabidopsis

Plant J. 2022 Apr;110(2):499-512. doi: 10.1111/tpj.15684. Epub 2022 Feb 26.


Succinate dehydrogenase (SDH, complex II), which plays an essential role in mitochondrial respiration and tricarboxylic acid metabolism, requires the assembly of eight nuclear-encoded subunits and the insertion of various cofactors. Here, we report on the characterization of an Arabidopsis thaliana leucine-tyrosine-arginine (LYR) protein family member SDHAF1, (At2g39725) is a factor required for SDH activity. SDHAF1 is located in mitochondria and can fully complement the yeast SDHAF1 deletion strain. Knockdown of SDHAF1 using RNA interference resulted in a decrease in seedling hypocotyl elongation and reduced SDH activity. Proteomic analyses revealed a decreased abundance of various SDH subunits and assembly factors. Protein interaction assays revealed that SDHAF1 can interact exclusively with the Fe-S cluster-containing subunit SDH2 and HSCB, a cochaperone involved in Fe-S cluster complex recruitment. Therefore, we propose that in Arabidopsis, SDHAF1 plays a role in the biogenesis of SDH2 to form the functional complex II, which is essential for mitochondrial respiration and metabolism.

Keywords: assembly factors; complex II; iron-sulfur cluster insertion; mitochondrial metabolism; succinate dehydrogenase.

MeSH terms

  • Arabidopsis* / genetics
  • Arabidopsis* / metabolism
  • Mitochondrial Proteins / genetics
  • Mitochondrial Proteins / metabolism
  • Proteomics
  • Saccharomyces cerevisiae / metabolism
  • Succinate Dehydrogenase / genetics
  • Succinate Dehydrogenase / metabolism


  • Mitochondrial Proteins
  • Succinate Dehydrogenase