orf250 encodes a second subunit of an ABC-type heme transporter in Oenothera mitochondria

Mol Gen Genet. 1995 Jan 20;246(2):166-73. doi: 10.1007/BF00294679.


A highly transcribed region in Oenothera mitochondria codes for an open reading frame comprising 250 condons (orf250). This open reading frame shows high sequence similarity to the helC gene of Rhodobacter capsulatus which encodes a subunit of a proposed ABC-type heme transporter. Transcripts of orf250 are edited by cytidine to uridine transitions at 29 sites, altering 10% of all encoded amino acids. Genes homologous to helC have also been found in the bacteria Bradyrhizobium japonicum and Escherichia coli, and are conserved in mitochondria of Marchantia polymorpha, Daucus carota, and Arabidopsis thaliana. In bacteria these genes belong to operons that are involved in the biogenesis of c-type cytochromes. The bacterial gene organization is partly conserved in Marchantia, but altered in the mitochondrial genome of Oenothera.

Publication types

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

MeSH terms

  • ATP-Binding Cassette Transporters / genetics*
  • Amino Acid Sequence
  • Base Sequence
  • Biological Transport
  • Cloning, Molecular
  • Cytochrome c Group / biosynthesis
  • DNA, Mitochondrial / genetics
  • Genes, Plant / genetics*
  • Heme / metabolism*
  • Mitochondria / genetics*
  • Molecular Sequence Data
  • Plastids / genetics
  • Polymerase Chain Reaction
  • RNA Editing
  • RNA, Transfer / genetics
  • Restriction Mapping
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid


  • ATP-Binding Cassette Transporters
  • Cytochrome c Group
  • DNA, Mitochondrial
  • Heme
  • RNA, Transfer

Associated data

  • GENBANK/X78035
  • GENBANK/X78036
  • GENBANK/X78037
  • GENBANK/X78038