Isolation of an Arabidopsis thaliana cDNA by complementation of a yeast abc1 deletion mutant deficient in complex III respiratory activity

Gene. 1998 Oct 9;221(1):117-25. doi: 10.1016/s0378-1119(98)00417-x.


The yeast Abc1 protein acts as a chaperone-like protein essential for the proper conformation and efficient functioning of the respiratory complex III. By functional complementation of a yeast abc1 mutant, we have identified an Arabidopsis thaliana cDNA that corresponds to a single copy gene and encodes a protein sharing 45% similarity with the yeast Abc1p protein. Cytochrome spectra and respiratory activity measurements have shown that the plant protein allows a partial restoration of the complex III activity. No major difference in the steady-state level of ABC1At mRNA was observed in various plant tissues, suggesting that ABC1At is constitutively expressed in A. thaliana. Phylogenetic analysis revealed that the Abc1At protein belongs to a large family of proteins composed of two eukaryotic and one prokaryotic subgroups differing by their degree of similarity and probably by their function.

MeSH terms

  • Amino Acid Sequence
  • Arabidopsis / genetics*
  • DNA, Complementary / genetics
  • DNA, Complementary / isolation & purification*
  • Electron Transport Complex III / genetics*
  • Fungal Proteins / genetics*
  • Gene Deletion
  • Gene Dosage
  • Gene Expression Regulation, Plant
  • Genetic Complementation Test
  • Molecular Sequence Data
  • Mutation
  • Phylogeny
  • Plant Proteins / genetics
  • Saccharomyces cerevisiae / genetics*
  • Saccharomyces cerevisiae Proteins*
  • Sequence Alignment
  • Sequence Homology, Amino Acid


  • COQ8 protein, S cerevisiae
  • DNA, Complementary
  • Fungal Proteins
  • Plant Proteins
  • Saccharomyces cerevisiae Proteins
  • Electron Transport Complex III