期刊
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
卷 116, 期 15, 页码 7272-7277出版社
NATL ACAD SCIENCES
DOI: 10.1073/pnas.1814818116
关键词
V-ATPase; STV1; VPH1; cryo-EMI; membrane protein
资金
- Canadian Institutes of Health Research [MOP81294]
- Canada Research Chairs Program
- European Research Council [69551-ENABLE]
- Wellcome Trust Investigator Award [104633/Z/14/Z]
- Engineering and Physical Sciences Research Council
- Canadian Foundation for Innovation
- Ontario Research Fund
- Wellcome Trust [104633/Z/14/Z] Funding Source: Wellcome Trust
Proton-translocating vacuolar-type ATPases (V-ATPases) are necessary for numerous processes in eukaryotic cells, including receptor-mediated endocytosis, protein maturation, and lysosomal acidification. In mammals, V-ATPase subunit isoforms are differentially targeted to various intracellular compartments or tissues, but how these subunit isoforms influence enzyme activity is not clear. In the yeast Saccharomyces cerevisiae, isoform diversity is limited to two different versions of the proton-translocating subunit a: Vph1p, which is targeted to the vacuole, and Stv1p, which is targeted to the Golgi apparatus and endosomes. We show that purified V-ATPase complexes containing Vph1p have higher ATPase activity than complexes containing Stv1p and that the relative difference in activity depends on the presence of lipids. We also show that V-0 complexes containing Stv1p could be readily purified without attached V-1 regions. We used this effect to determine structures of the membrane-embedded V-0 region with Stv1p at 3.1-angstrom resolution, which we compare with a structure of the V-0 region with Vph1p that we determine to 3.2-angstrom resolution. These maps reveal differences in the surface charge near the cytoplasmic proton half-channel. Both maps also show the presence of bound lipids, as well as regularly spaced densities that may correspond to ergosterol or bound detergent, around the c-ring.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据