Characterization of the human SDHD gene encoding the small subunit of cytochrome b (cybS) in mitochondrial succinate-ubiquinone oxidoreductase

Biochim Biophys Acta. 1999 Aug 4;1412(3):295-300. doi: 10.1016/s0005-2728(99)00071-7.


We have mapped large (cybL) and small (cybS) subunits of cytochrome b in the succinate-ubiquinone oxidoreductase (complex II) of human mitochondria to chromosome 1q21 and 11q23, respectively (H. Hirawake et al., Cytogenet. Cell Genet. 79 (1997) 132-138). In the present study, the human SDHD gene encoding cybS was cloned and characterized. The gene comprises four exons and three introns extending over 19 kb. Sequence analysis of the 5' promoter region showed several motifs for the binding of transcription factors including nuclear respiratory factors NRF-1 and NRF-2 at positions -137 and -104, respectively. In addition to this gene, six pseudogenes of cybS were isolated and mapped on the chromosome.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Cloning, Molecular
  • Cytochrome b Group / chemistry
  • Cytochrome b Group / genetics*
  • Electron Transport Complex II
  • Humans
  • Introns
  • Mitochondria, Liver / enzymology*
  • Molecular Sequence Data
  • Multienzyme Complexes / chemistry
  • Multienzyme Complexes / genetics*
  • Oxidoreductases / chemistry
  • Oxidoreductases / genetics*
  • Promoter Regions, Genetic
  • Restriction Mapping
  • Succinate Dehydrogenase / chemistry
  • Succinate Dehydrogenase / genetics*


  • Cytochrome b Group
  • Multienzyme Complexes
  • Oxidoreductases
  • Electron Transport Complex II
  • Succinate Dehydrogenase

Associated data

  • GENBANK/AB026906