The vacuolar proton-translocating ATPase is the principal energization mechanism that enables the yeast vacuole to perform most of its physiological functions. We have undertaken an examination of subunit-subunit interactions and assembly states of this enzyme. Yeast two-hybrid data indicate that Vma1p and Vma2p interact with each other and that Vma4p interacts with itself. Three-hybrid data indicate that the Vma4p self-interaction is stabilized by both Vma1p and Vma2p. Native gel electrophoresis reveals numerous partial complexes not previously described. In addition to a large stable cytoplasmic complex seen in wild-type, Deltavma3 and Deltavma5 strains, we see partial complexes in the Deltavma4 and Deltavma7 strains. All larger complexes are lost in the Deltavma1, Deltavma2, and Deltavma8 strains. We designate the large complex seen in wild-type cells containing at least subunits Vma1p, Vma2p, Vma4p, Vma7p, and Vma8p as the definitive V1 complex.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1074/jbc.271.17.10397 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Characterization of the complex involved in regulating V-ATPase activity of the vacuolar and endosomal membrane.
J Bioenerg Biomembr
October 2017
Faculty of Forestry, University of British Columbia, Vancouver, V6T 1Z4, Canada.
Regulator of the H-ATPase of the vacuolar and endosomal membranes (RAVE) is essential for the reversible assembly of H-ATPase. RAVE primarily consists of three subunits: Rav1p, Rav2p and Skp1p. To characterize these subunits, in this study, four strains derived from Saccharomyces cerevisiae BY4742 were constructed with a FLAG tag on the Rav1p and Rav2p subunits.
View Article and Find Full Text PDFA novel role for the yeast protein kinase Dbf2p in vacuolar H+-ATPase function and sorbic acid stress tolerance.
Microbiology (Reading)
December 2007
Centre for Biomolecular Sciences, School of Biology, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, UK.
In Saccharomyces cerevisiae, the serine-threonine protein kinase activity of Dbf2p is required for tolerance to the weak organic acid sorbic acid. Here we show that Dbf2p is required for normal phosphorylation of the vacuolar H(+)-ATPase (V-ATPase) A and B subunits Vma1p and Vma2p. Loss of V-ATPase activity due to bafilomycin treatment or deletion of either VMA1 or VMA2 resulted in sorbic acid hypersensitivity and impaired vacuolar acidification, phenotypes also observed in both a kinase-inactive dbf2 mutant and cells completely lacking DBF2 (dbf2Delta).
View Article and Find Full Text PDFA proteome analysis of the yeast response to the herbicide 2,4-dichlorophenoxyacetic acid.
Proteomics
May 2005
Biological Sciences Research Group, Centro de Engenharia Biológica e Química, Instituto Superior Técnico, Lisbon, Portugal.
The intensive use of herbicides may give rise to a number of toxicological problems in non-target organisms and has led to the emergence of resistant weeds. To gain insights into the mechanisms of adaptation to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), we have identified variations in protein expression level in the eukaryotic experimental model Saccharomyces cerevisiae exposed to herbicide aggression, based on two-dimensional gel electrophoresis. We show results suggesting that during the adaptation period preceding the resumption of inhibited exponential growth under herbicide stress, the antioxidant enzyme Ahp1p and the heat shock proteins Hsp12p and Ssb2p (or Ssb1p) are present in higher amounts.
View Article and Find Full Text PDFDefined sites of interaction between subunits E (Vma4p), C (Vma5p), and G (Vma10p) within the stator structure of the vacuolar H+-ATPase.
Biochemistry
March 2005
School of Biochemistry and Microbiology, University of Leeds, Leeds LS2 9JT, United Kingdom.
Vacuolar H(+)-ATPases (V-ATPases) are multi-subunit membrane proteins that couple ATP hydrolysis to the extrusion of protons from the cytoplasm. Although they share a common macromolecular architecture and rotational mechanism with the F(1)F(0)-ATPases, the organization of many of the specialized V-ATPase subunits within this rotary molecular motor remains uncertain. In this study, we have identified sequence segments involved in linking putative stator subunits in the Saccharomyces V-ATPase.
View Article and Find Full Text PDFSubstrate- and inhibitor-induced conformational changes in the yeast V-ATPase provide evidence for communication between the catalytic and proton-translocating sectors.
J Biol Chem
September 1999
Hospital for Sick Children, Toronto, Ontario, M5G 1X8, Canada.
The vacuolar-type H(+)-ATPases (V-ATPases) are composed of two distinct sectors, a catalytic complex (V(1)) involved in ATP hydrolysis and a membrane-associated complex (V(0)) mediating proton translocation across a lipid bilayer. To date, little is known about the mechanism by which these two functions are coupled. We sought to examine the impact of nucleotide and cation binding on the structure of the core components of the catalytic complex and to determine whether conformational changes within the catalytic complex impact subunits of the membrane-associated complex.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!