Phenotypes of yeast mutants lacking the mitochondrial protein Pet20p.
The pet20-delta deletion in Saccharomyces cerevisiae causes diminished growth on media containing non-fermentable carbon sources when incubated at both above and below the 30 degrees C optimal growth temperature. Furthermore, the pet20-delta strain has a greatly reduced level of cytochrome c, especially at 37 degrees C. The pet20-delta strain was sensitive to high NaCl and CaCl2 concentrations, hydrogen peroxide, oligomycin, polymixin B, amphotericin B and fluconazole. Biochemical fractionation and immunofluorescence staining demonstrated that Pet20p is located primarily in the mitochondria. Rhodamine B staining of pet20-delta cells showed an altered mitochondrial staining, indicating the possible lack of the mitochondrial membrane potential. We suggest that PET20 encodes a protein required for proper assembly or maintenance of mitochondrial components, but does not serve an enzymatic role. It is also possible that Pet20p may constitute a non-catalytic subunit of an uncharacterized mitochondrial complex or serve as a transporter or a coupling factor.
Department of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester, New York 14642, USA.
Bogdan
B
Polevoda
Yana
Y
Panciera
Steven P
SP
Brown
Jun
J
Wei
Fred
F
Sherman
D000595:Amino Acid Sequence; D000935:Antifungal Agents / Q000494:pharmacology; D045304:Cytochromes c / Q000378:metabolism*; D004271:DNA, Fungal / Q000235:genetics; D005456:Fluorescent Dyes / Q000737:chemistry; D008565:Membrane Proteins / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000172:deficiency* / Q000378:metabolism; D008969:Molecular Sequence Data; D010641:Phenotype; D012235:Rhodamines / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D016415:Sequence Alignment; D013347:Subcellular Fractions
D000935:Antifungal Agents; D004271:DNA, Fungal; D005456:Fluorescent Dyes; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D012235:Rhodamines; D029701:Saccharomyces cerevisiae Proteins; D045304:Cytochromes c; C029773:rhodamine B