The yeast H+-ATPase Pma1 promotes Rag/Gtr-dependent TORC1 activation in response to H+-coupled nutrient uptake
Abstract
The yeast Target of Rapamycin Complex 1 (TORC1) plays a central role in controlling growth. How amino acids and other nutrients stimulate its activity via the Rag/Gtr GTPases remains poorly understood. We here report that the signal triggering Rag/Gtr-dependent TORC1 activation upon amino-acid uptake is the coupled H+ influx catalyzed by amino-acid/H+ symporters. H+-dependent uptake of other nutrients, ionophore-mediated H+ diffusion, and inhibition of the vacuolar V-ATPase also activate TORC1. As the increase in cytosolic H+ elicited by these processes stimulates the compensating H+-export activity of the plasma membrane H+-ATPase (Pma1), we have examined whether this major ATP-consuming enzyme might be involved in TORC1 control. We find that when the endogenous Pma1 is replaced with a plant H+-ATPase, H+ influx or increase fails to activate TORC1. Our results show that H+ influx coupled to nutrient uptake stimulates TORC1 activity and that Pma1 is a key actor in this mechanism.
Article and author information
Author details
Funding
Fonds De La Recherche Scientifique - FNRS (3.4.592.08.F)
- Bruno Andre
Fonds pour la Formation à la Recherche dans l'Industrie et dans l'Agriculture (21074048)
- Elie Saliba
Fonds De La Recherche Scientifique - FNRS (22396499)
- Christos Gournas
Fonds De La Recherche Scientifique - FNRS (30274494)
- Minoas Evangelinos
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Saliba et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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