MyJournals Home  

RSS FeedsFunctional reconstitution of vacuolar H+-ATPase from Vo proton channel and mutant V1-ATPase provides insight into the mechanism of reversible disassembly [Membrane Biology] (Journal of Biological Chemistry)

 
 

19 april 2019 14:01:32

 
Functional reconstitution of vacuolar H+-ATPase from Vo proton channel and mutant V1-ATPase provides insight into the mechanism of reversible disassembly [Membrane Biology] (Journal of Biological Chemistry)
 




The vacuolar H+-ATPase (V-ATPase; V1Vo-ATPase) is an ATP-dependent proton pump that acidifies subcellular compartments in all eukaryotic organisms. V-ATPase activity is regulated by reversible disassembly into autoinhibited V1-ATPase and Vo proton channel subcomplexes, a process that is poorly understood on the molecular level. V-ATPase is a rotary motor, and recent structural analyses have revealed different rotary states for disassembled V1 and Vo, a mismatch that is likely responsible for their inability to reconstitute into holo V-ATPase in vitro. Here, using the model organism Saccharomyces cerevisiae, we show that a key impediment for binding of V1 to Vo is the conformation of the inhibitory C-terminal domain of subunit H (HCT). Using biolayer interferometry and biochemical analyses of purified mutant V1-ATPase and Vo proton channel reconstituted into vacuolar lipid-containing nanodiscs, we further demonstrate that disruption of HCT`s V1-binding site facilitates assembly of a functionally coupled and stable V1Vo-ATPase. Unlike WT, this mutant enzyme was resistant to MgATP hydrolysis-induced dissociation, further highlighting HCT`s role in the mechanism of V-ATPase regulation. Our findings provide key insight into the molecular events underlying regulation of V-ATPase activity by reversible disassembly.


Del.icio.us Digg Facebook Google StumbleUpon Twitter
 
14 viewsCategory: Biochemistry
 
The stress granule protein G3BP1 binds viral dsRNA and RIG-I to enhance interferon-{beta} response [Immunology] (Journal of Biological Chemistry)
Stimulation of heat shock protein 90 chaperone function through binding of a novobiocin analog KU-32 [Molecular Biophysics] (Journal of Biological Chemistry)
 
 
blog comments powered by Disqus


MyJournals.org
The latest issues of all your favorite science journals on one page

Username:
Password:

Register | Retrieve

Search:

Biochemistry

Use these buttons to bookmark us:
Del.icio.us Digg Facebook Google StumbleUpon Twitter


Valid HTML 4.01 Transitional
Copyright © 2008 - 2019 Indigonet Services B.V.. Contact: Tim Hulsen. Read here our privacy notice.
Other websites of Indigonet Services B.V.: Nieuws Vacatures News Tweets Travel Photos Nachrichten Indigonet Finances Leer Mandarijn