Pleiotropic mutations within two yeast mitochondrial cytochrome genes block mRNA processing

Cell. 1979 Dec;18(4):1209-15. doi: 10.1016/0092-8674(79)90233-2.


The mRNAs from two yeast mitochondrial genes cob-box (cytochrome b) and oxi-3 (cytochrome oxidase 40,000 dalton subunit) are processed from large (7-10 kb) precursors. Certain mutations in each gene block the maturation of the RNAs from both genes at a variety of specific steps. The pleiotropic cytochrome b mutants seem to lack a functional trans-acting RNA required for the processing of both messengers. In contrast, the oxi-3 mutants may act by producing an activity that inhibits specific steps.

MeSH terms

  • Cytochromes / genetics*
  • Electron Transport Complex IV / genetics
  • Genes*
  • Mitochondria
  • Mutation
  • Nucleic Acid Precursors / metabolism*
  • RNA, Fungal / metabolism*
  • RNA, Messenger / metabolism*
  • Yeasts / genetics*


  • Cytochromes
  • Nucleic Acid Precursors
  • RNA, Fungal
  • RNA, Messenger
  • Electron Transport Complex IV