title: Isolation and sequence of the gene for iso-2-cytochrome c in Saccharomyces cerevisiae.
abstract: The two apocytochrome c proteins of yeast are coded for by separate genes. Iso-2-cytochrome c differs from the iso-1 protein at 17 positions within a homologous sequence of 108 amino acids. The previously cloned iso-1-cytochrome c coding sequence has been used to identify lambda-yeast recombinant phage containing the gene for iso-2-cytochrome c. The latter protein contains the dipeptide Ala-Ala which is coded for by the nucleic acid sequence G-C-N-G-C-N. The recognition specificity of restriction endonuclease Fnu4HI for G-C-N-G-C provided a rapid means of locating the region of the cloned fragment which codes for iso-2-cytochrome c. The DNA sequence of this gene has been determined and compared with that of the iso-1-cytochrome c locus. There is no intervening sequence within the gene for iso-2-cytochrome c. At 45 of the 91 positions for which iso-1- and iso-2-cytochrome c have the same amino acid, the codons differ. Such third position variation does not occur within the region coding for amino acids 70-80, the protein sequence that is also most conserved among all eukaryotic cytochromes c.
mesh_terms: D001059:Apoproteins / Q000235:genetics; D001483:Base Sequence; D003062:Codon; D003574:Cytochrome c Group / Q000235:genetics*; D004262:DNA Restriction Enzymes; D004271:DNA, Fungal / Q000235:genetics; D004274:DNA, Recombinant; D005796:Genes; D012333:RNA, Messenger / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics*
chemical_list: D001059:Apoproteins; D003062:Codon; D003574:Cytochrome c Group; D004271:DNA, Fungal; D004274:DNA, Recombinant; D012333:RNA, Messenger; D004262:DNA Restriction Enzymes