Open AccessTag‐mediated isolation of yeast mitochondrial ribosome and mass spectrometric identification of its new components
Author(s) -
Gan Xiang,
Kitakawa Madoka,
Yoshino Kenichi,
Oshiro Noriko,
Yonezawa Kazuyoshi,
Isono Katsumi
Publication year - 2002
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1046/j.1432-1033.2002.03226.x
Subject(s) - ribosome , mitochondrial ribosome , protein subunit , ribosomal protein , ribosomal rna , yeast , eukaryotic large ribosomal subunit , biochemistry , biology , saccharomyces cerevisiae , eukaryotic ribosome , microbiology and biotechnology , gene , rna
Mitochondrial ribosomal proteins (mrps) of the budding yeast, Saccharomyces cerevisiae , have been extensively characterized genetically and biochemically. However, the list of the genes encoding individual mrps is still not complete and quite a few of the mrps are only predicted from their similarity to bacterial ribosomal proteins. We have constructed a yeast strain in which one of the small subunit proteins, termed Mrp4, was tagged with S‐peptide and used for affinity purification of mitochondrial ribosome. Mass spectrometric analysis of the isolated proteins detected most of the small subunit mrps which were previously identified or predicted and about half of the large subunit mrps. In addition, several proteins of unknown function were identified. To confirm their identity further, we added tags to these proteins and analyzed their localization in subcellular fractions. Thus, we have newly established Ymr158w (MrpS8), Ypl013c (MrpS16), Ymr188c (MrpS17) and Ygr165w (MrpS35) as small subunit mrps and Img1, Img2, Ydr116c (MrpL1), Ynl177c (MrpL22), Ynr022c (MrpL50) and Ypr100w (MrpL51) as large subunit mrps.