The V-ATPase membrane domain is a sensor of granular pH that controls the exocytotic machinery

Sandrine Poëa-Guyon; Mohamed Raafet Ammar; Marie Erard; Muriel Amar; Alexandre W Moreau; Philippe Fossier; Vincent Gleize; Nicolas Vitale; Nicolas Morel

doi:10.1083/jcb.201303104

The V-ATPase membrane domain is a sensor of granular pH that controls the exocytotic machinery

J Cell Biol. 2013 Oct 28;203(2):283-98. doi: 10.1083/jcb.201303104.

Authors

Sandrine Poëa-Guyon¹, Mohamed Raafet Ammar, Marie Erard, Muriel Amar, Alexandre W Moreau, Philippe Fossier, Vincent Gleize, Nicolas Vitale, Nicolas Morel

Affiliation

¹ Centre de Neurosciences Paris-Sud, Centre National de la Recherche Scientifique Unité Mixte de Recherche 8195 and Université Paris-Sud, F-91405 Orsay, France.

Abstract

Several studies have suggested that the V0 domain of the vacuolar-type H(+)-adenosine triphosphatase (V-ATPase) is directly implicated in secretory vesicle exocytosis through a role in membrane fusion. We report in this paper that there was a rapid decrease in neurotransmitter release after acute photoinactivation of the V0 a1-I subunit in neuronal pairs. Likewise, inactivation of the V0 a1-I subunit in chromaffin cells resulted in a decreased frequency and prolonged kinetics of amperometric spikes induced by depolarization, with shortening of the fusion pore open time. Dissipation of the granular pH gradient was associated with an inhibition of exocytosis and correlated with the V1-V0 association status in secretory granules. We thus conclude that V0 serves as a sensor of intragranular pH that controls exocytosis and synaptic transmission via the reversible dissociation of V1 at acidic pH. Hence, the V-ATPase membrane domain would allow the exocytotic machinery to discriminate fully loaded and acidified vesicles from vesicles undergoing neurotransmitter reloading.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Catecholamines / metabolism
Cattle
Chromaffin Cells / enzymology
Chromaffin Cells / metabolism
Exocytosis* / drug effects
Exocytosis* / radiation effects
Hydrogen-Ion Concentration
Kinetics
Light
Membrane Fusion
Mice
Neurons / drug effects
Neurons / enzymology*
Neurons / metabolism
Neurons / radiation effects
PC12 Cells
Protein Structure, Tertiary
RNA Interference
Rats
Recombinant Fusion Proteins / metabolism
Secretory Vesicles / drug effects
Secretory Vesicles / enzymology*
Secretory Vesicles / metabolism
Secretory Vesicles / radiation effects
Synaptic Potentials
Synaptic Transmission* / drug effects
Synaptic Transmission* / radiation effects
Synaptic Vesicles / drug effects
Synaptic Vesicles / enzymology*
Synaptic Vesicles / metabolism
Synaptic Vesicles / radiation effects
Transfection
Vacuolar Proton-Translocating ATPases / genetics
Vacuolar Proton-Translocating ATPases / metabolism*

Substances

Catecholamines
Recombinant Fusion Proteins
Vacuolar Proton-Translocating ATPases
vacuolar ATPase V0 subunit A1, rat