Mutations in the structural gene for cytochrome c result in deficiency of both cytochromes aa3 and c in Neurospora crassa.
The cyt-12-12 mutant of Neurospora crassa is characterized by slow growth and a deficiency of spectrophotometrically-detectable cytochromes aa3 and c. Using a sib-selection procedure we have isolated the cyt-12+ allele from a cosmid library of N. crassa genomic DNA. Characterization of the cyt-12+ allele reveals that it encodes the structural gene for cytochrome c. DNA sequence analysis of the cyt-12-12 allele revealed a mutation in the cytochrome c coding sequence that results in replacement of a glycine residue, which is invariant in the cytochrome c of other species, with an aspartic acid. Genetic analysis confirms that cyt-12-12 is allelic with the previously-characterized cyc-1-1 mutant, which was also shown to affect the single locus encoding cytochrome c in N. crassa. We suggest that the amount of functional cytochrome c present in mitochondria influences the level of cytochrome aa3.
Bottorff
D A
DA
Department of Genetics, University of Alberta, Edmonton, Canada.
Parmaksizoglu
S
S
Lemire
E G
EG
Coffin
J W
JW
Bertrand
H
H
Nargang
F E
FE
D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D003574:Cytochrome c Group / Q000235:genetics* / Q000378:metabolism; D004271:DNA, Fungal / Q000235:genetics; D003576:Electron Transport Complex IV / Q000235:genetics* / Q000378:metabolism; D005800:Genes, Fungal; D006801:Humans; D008928:Mitochondria / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D009492:Neurospora crassa / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D010641:Phenotype; D017386:Sequence Homology, Amino Acid
D003574:Cytochrome c Group; D004271:DNA, Fungal; D003576:Electron Transport Complex IV