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
A novel membrane-bound glutathione S-transferase functions in the stationary phase of the yeast Saccharomyces cerevisiae.
AuthorsChoi JH, Lou W, Vancura A
JournalJ Biol Chem
PubMed ID9792709
'The glutathione S-transferases (GSTs) represent a significant group of detoxification enzymes that play an important role in drug resistance in all eukaryotic species. In this paper we report an identification and characterization of the two Saccharomyces cerevisiae genes, GTT1 and GTT2 (glutathione transferase 1 and 2), coding for functional GST ... 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
VMA12 encodes a yeast endoplasmic reticulum protein required for vacuolar H+-ATPase assembly.
AuthorsJackson DD, Stevens TH
JournalJ Biol Chem
PubMed ID9325326
'The Saccharomyces cerevisiae vacuolar membrane proton-translocating ATPase (V-ATPase) can be divided into a peripheral membrane complex (V1) containing at least eight polypeptides of 69, 60, 54, 42, 32, 27, 14, and 13 kDa, and an integral membrane complex (V0) containing at least five polypeptides of 100, 36, 23, 17, and ... 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
ATP-dependent transport of reduced glutathione on YCF1, the yeast orthologue of mammalian multidrug resistance associated proteins.
AuthorsRebbeor JF, Connolly GC, Dumont ME, Ballatori N
JournalJ Biol Chem
PubMed ID9837923
'The transport systems involved in the export of cellular reduced glutathione (GSH) have not been identified, although recent studies implicate a role for some of the multidrug resistance associated proteins (MRP), including MRP1 and MRP2. The present study examined the hypothesis that the yeast orthologue of MRP, Ycf1p, mediates ATP-dependent ... More
Two separate signals act independently to localize a yeast late Golgi membrane protein through a combination of retrieval and retention.
AuthorsBryant NJ, Stevens TH
JournalJ Cell Biol
PubMed ID9015300
'The localization of proteins to late-Golgi membranes (TGN) of Saccharomyces cerevisiae is conferred by targeting motifs containing aromatic residues in the cytosolic domains of these proteins. These signals could act by directing retrieval from a post-Golgi compartment or by preventing exit from the TGN. To investigate the mechanism of localization ... More
Vta1p and Vps46p regulate the membrane association and ATPase activity of Vps4p at the yeast multivesicular body.
Previous two-hybrid analysis of the 17 soluble class E Vps yeast proteins revealed that Vps46p/Did2p interacts with Vta1p and the AAA (ATPase associated with a variety of cellular activities) ATPase Vps4p. Here we report that the binding of Vps46p to Vps4p and Vta1p is direct and not mediated by additional ... More
Identification of an organelle-specific myosin V receptor.
Class V myosins are widely distributed among diverse organisms and move cargo along actin filaments. Some myosin Vs move multiple types of cargo, where the timing of movement and the destinations of selected cargoes are unique. Here, we report the discovery of an organelle-specific myosin V receptor. Vac17p, a novel ... More
Novel localization of a Na+/H+ exchanger in a late endosomal compartment of yeast. Implications for vacuole biogenesis.
AuthorsNass R, Rao R
JournalJ Biol Chem
PubMed ID9694857
Na+/H+ exchangers catalyze the electrically silent countertransport of Na+ and H+, controlling the transmembrane movement of salt, water, and acid-base equivalents, and are therefore critical for Na+ tolerance, cell volume control, and pH regulation. In contrast to numerous well studied plasma membrane isoforms (NHE1-4), much less is known about intracellular ... 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
Vma9p (subunit e) is an integral membrane V0 subunit of the yeast V-ATPase.
AuthorsCompton MA, Graham LA, Stevens TH
JournalJ Biol Chem
PubMed ID16569636
The Saccharomyces cerevisiae vacuolar proton-translocating ATPase (V-ATPase) is composed of 14 subunits distributed between a peripheral V1 subcomplex and an integral membrane V0 subcomplex. Genome-wide screens have led to the identification of the newest yeast V-ATPase subunit, Vma9p. Vma9p (subunit e) is a small hydrophobic protein that is conserved from ... More
Long chain base tolerance in Saccharomyces cerevisiae is induced by retrograde signals from the mitochondria.
AuthorsPanwar SL, Moye-Rowley WS
JournalJ Biol Chem
PubMed ID16407254
Saccharomyces cerevisiae cells lacking their mitochondrial DNA (rho0 cells) respond to this loss of genetic information by induction of a program of nuclear gene expression called the retrograde response. Expression of genes involved in multidrug resistance and sphingolipid biosynthesis is coordinately induced in rho0 cells by the zinc cluster transcription ... More
Assembly of the yeast vacuolar H+-ATPase occurs in the endoplasmic reticulum and requires a Vma12p/Vma22p assembly complex.
AuthorsGraham LA, Hill KJ, Stevens TH
JournalJ Cell Biol
PubMed ID9660861
Three previously identified genes from Saccharomyces cerevisiae, VMA12, VMA21, and VMA22, encode proteins localized to the endoplasmic reticulum (ER). These three proteins are required for the biogenesis of a functional vacuolar ATPase (V-ATPase), but are not part of the final enzyme complex. Subcellular fractionation and chemical cross-linking studies have revealed ... More
Multilamellar endosome-like compartment accumulates in the yeast vps28 vacuolar protein sorting mutant.
AuthorsRieder SE, Banta LM, Köhrer K, McCaffery JM, Emr SD
JournalMol Biol Cell
PubMed ID8817003
In the yeast Saccharomyces cerevisiae, vacuolar proteins such as carboxypeptidase Y transit from the Golgi to the lysosome-like vacuole via an endosome-like intermediate compartment. The vacuolar protein sorting (vps) mutant vps28, a member of the "class E" vps mutants, accumulates vacuolar, endocytic, and late Golgi markers in an aberrant endosome-like ... More
C5a receptor oligomerization. II. Fluorescence resonance energy transfer studies of a human G protein-coupled receptor expressed in yeast.
Recent studies demonstrate that members of the superfamily of G protein-coupled receptors (GPCRs) form oligomers both in vitro and in vivo. The mechanisms by which GPCRs oligomerize and the roles of accessory proteins in this process are not well understood. We used disulfide-trapping experiments to show that C5a receptors, expressed ... More