An mRNA maturase is encoded by the first intron of the mitochondrial gene for the subunit I of cytochrome oxidase in S. cerevisiae

Cell. 1983 Dec;35(3 Pt 2):733-42. doi: 10.1016/0092-8674(83)90106-x.


We have localized ten oxi3- mutations in the first, al1, intron of the coxl gene. All are splicing deficient, being unable to excise the intron. Complementation experiments disclose several domains in the intron al1: the 5'-proximal and 3'-proximal domains harbor cis-dominant mutations, while trans-recessive ones are located in the intron's open reading frame. Comprehensive analyses of allele-specific polypeptides accumulating in mutants show that they result from the translation of the intron's ORF. We conclude that a specific mRNA maturase involved in splicing of oxidase mRNA is encoded by the intron al1 in a manner similar to the cytochrome b mRNA maturase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chromosome Mapping
  • DNA, Mitochondrial / genetics*
  • Electron Transport Complex IV / genetics*
  • Endoribonucleases*
  • Genes
  • Macromolecular Substances
  • Molecular Weight
  • Nucleotidyltransferases / genetics
  • Protein Biosynthesis
  • Saccharomyces cerevisiae / genetics*
  • Transcription, Genetic


  • DNA, Mitochondrial
  • Macromolecular Substances
  • Electron Transport Complex IV
  • Nucleotidyltransferases
  • mRNA maturase
  • Endoribonucleases