Assembly and targeting of peripheral and integral membrane subunits of the yeast vacuolar H(+)-ATPase.
AuthorsKane PM, Kuehn MC, Howald-Stevenson I, Stevens TH
JournalJ Biol Chem
PubMed ID1530931
Previous purification and characterization of the yeast vacuolar proton-translocating ATPase (H(+)-ATPase) have indicated that it is a multisubunit complex consisting of both integral and peripheral membrane subunits (Uchida, E., Ohsumi, Y., and Anraku, Y. (1985) J. Biol. Chem. 260, 1090-1095; Kane, P. M., Yamashiro, C. T., and Stevens, T. H. ... More
Effects of human a3 and a4 mutations that result in osteopetrosis and distal renal tubular acidosis on yeast V-ATPase expression and activity.
AuthorsOchotny N, Van Vliet A, Chan N, Yao Y, Morel M, Kartner N, von Schroeder HP, Heersche JN, Manolson MF
JournalJ Biol Chem
PubMed ID16840787
'V-ATPases are multimeric proton pumps. The 100-kDa "a" subunit is encoded by four isoforms (a1-a4) in mammals and two (Vph1p and Stv1p) in yeast. a3 is enriched in osteoclasts and is essential for bone resorption, whereas a4 is expressed in the distal nephron and acidifies urine. Mutations in human a3 ... More
Saccharomyces cerevisiae lacking Btn1p modulate vacuolar ATPase activity to regulate pH imbalance in the vacuole.
AuthorsPadilla-López S, Pearce DA
JournalJ Biol Chem
PubMed ID16423829
'The vacuolar H(+)-ATPase (V-ATPase) along with ion channels and transporters maintains vacuolar pH. V-ATPase ATP hydrolysis is coupled with proton transport and establishes an electrochemical gradient between the cytosol and vacuolar lumen for coupled transport of metabolites. Btn1p, the yeast homolog to human CLN3 that is defective in Batten disease, ... More
PKR1 encodes an assembly factor for the yeast V-type ATPase.
AuthorsDavis-Kaplan SR, Compton MA, Flannery AR, Ward DM, Kaplan J, Stevens TH, Graham LA
JournalJ Biol Chem
PubMed ID16926153
'Deletion of the yeast gene PKR1 (YMR123W) results in an inability to grow on iron-limited medium. Pkr1p is localized to the membrane of the endoplasmic reticulum. Cells lacking Pkr1p show reduced levels of the V-ATPase subunit Vph1p due to increased turnover of the protein in mutant cells. Reduced levels of ... More
Subunit D (Vma8p) of the yeast vacuolar H+-ATPase plays a role in coupling of proton transport and ATP hydrolysis.
AuthorsXu T, Forgac M
JournalJ Biol Chem
PubMed ID10801866
'To investigate the function of subunit D in the vacuolar H(+)-ATPase (V-ATPase) complex, random and site-directed mutagenesis was performed on the VMA8 gene encoding subunit D in yeast. Mutants were selected for the inability to grow at pH 7.5 but the ability to grow at pH 5.5. Mutations leading to ... More
Biochemical characterization of the yeast vacuolar H(+)-ATPase.
AuthorsKane PM, Yamashiro CT, Stevens TH
JournalJ Biol Chem
PubMed ID2478556
'The yeast vacuolar proton-translocating ATPase was isolated by two different methods. A previously reported purification of the enzyme (Uchida, E., Ohsumi, Y., and Anraku, Y. (1985) J. Biol. Chem. 260, 1090-1095) was repeated. This procedure consisted of isolation of vacuoles, solubilization with the zwitterionic detergent ZW3-14, and glycerol gradient centrifugation ... More
Site-directed mutagenesis of the yeast V-ATPase A subunit.
AuthorsLiu Q, Leng XH, Newman PR, Vasilyeva E, Kane PM, Forgac M
JournalJ Biol Chem
PubMed ID9115229
'To investigate the function of residues at the catalytic nucleotide binding site of the V-ATPase, we have carried out site-directed mutagenesis of the VMA1 gene encoding the A subunit of the V-ATPase in yeast. Of the three cysteine residues that are conserved in all A subunits sequenced thus far, two ... More
Photoaffinity labeling of wild-type and mutant forms of the yeast V-ATPase A subunit by 2-azido-[(32)P]ADP.
AuthorsMacLeod KJ, Vasilyeva E, Merdek K, Vogel PD, Forgac M
JournalJ Biol Chem
PubMed ID10551850
'Molecular modeling studies have previously suggested the possible presence of four aromatic residues (Phe(452), Tyr(532), Tyr(535), and Phe(538)) near the adenine binding pocket of the catalytic site on the yeast V-ATPase A subunit (MacLeod, K. J., Vasilyeva, E., Baleja, J. D., and Forgac, M. (1998) J. Biol. Chem. 273, 150-156). ... More
Helical interactions and membrane disposition of the 16-kDa proteolipid subunit of the vacuolar H(+)-ATPase analyzed by cysteine replacement mutagenesis.
Theoretical mechanisms of proton translocation by the vacuolar H(+)-ATPase require that a transmembrane acidic residue of the multicopy 16-kDa proteolipid subunit be exposed at the exterior surface of the membrane sector of the enzyme, contacting the lipid phase. However, structural support for this theoretical mechanism is lacking. To address this, ... More
Partial assembly of the yeast vacuolar H(+)-ATPase in mutants lacking one subunit of the enzyme.
AuthorsDoherty RD, Kane PM
JournalJ Biol Chem
PubMed ID8344963
Partial assembly of the peripheral and integral membrane sectors of the yeast vacuolar H(+)-ATPase has been detected in mutants lacking one subunit of the enzyme. Assembled complexes of the vacuolar H(+)-ATPase could be immunoprecipitated from biosynthetically labeled wild-type cells using monoclonal antibodies specific for the 69- and 60-kDa subunits of ... More