Open AccessThe mitochondrial outer membrane protein Mas22p is essential for protein import and viability of yeast.
Author(s) -
Trevor Lithgow,
Tina Junne,
Kitaru Suda,
Sabine Gratzer,
Gottfried Schatz
Publication year - 1994
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.91.25.11973
Subject(s) - intermembrane space , mitochondrial carrier , mitochondrial intermembrane space , mitochondrion , translocase of the inner membrane , biology , bacterial outer membrane , microbiology and biotechnology , hspa9 , translocase of the outer membrane , mitochondrial membrane transport protein , atp–adp translocase , cytosol , protein targeting , vesicle associated membrane protein 8 , inner mitochondrial membrane , mutant , saccharomyces cerevisiae , yeast , membrane protein , biochemistry , gene , peptide sequence , membrane , enzyme , escherichia coli
We have cloned the gene encoding the protein Mas22p, which spans the outer membrane of yeast mitochondria. Cells that completely lack Mas22p are inviable. The plasmid-borne MAS22 gene suppresses several defects resulting from the deletion of one or more of the mitochondrial protein import receptors. Defects of Mas20p-deficient cells are explained by the reduced level of Mas22p in these mutants. Mas22p has one acidic domain in the cytosol and a second acidic domain in the mitochondrial intermembrane space. We suggest that these domains of Mas22p on either side of the outer membrane function as a relay system for transferring the basic targeting sequences of precursor proteins into the mitochondria.