The yeast H+-ATPase Pma1 promotes Rag/Gtr-dependent TORC1 activation in response to H+-coupled nutrient uptake

  1. Elie Saliba
  2. Minoas Evangelinos
  3. Christos Gournas
  4. Florent Corrillon
  5. Isabelle Georis
  6. Bruno Andre  Is a corresponding author
  1. Université Libre de Bruxelles (ULB), Belgium
  2. Institut de Recherches Microbiologiques Jean-Marie Wiame, Belgium

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

  1. Elie Saliba

    IBMM - Molecular Physiology of the Cell, Université Libre de Bruxelles (ULB), Gosselies, Belgium
    Competing interests
    The authors declare that no competing interests exist.
  2. Minoas Evangelinos

    IBMM - Molecular Physiology of the Cell, Université Libre de Bruxelles (ULB), Gosselies, Belgium
    Competing interests
    The authors declare that no competing interests exist.
  3. Christos Gournas

    IBMM - Molecular Physiology of the Cell, Université Libre de Bruxelles (ULB), Gosselies, Belgium
    Competing interests
    The authors declare that no competing interests exist.
  4. Florent Corrillon

    IBMM - Molecular Physiology of the Cell, Université Libre de Bruxelles (ULB), Gosselies, Belgium
    Competing interests
    The authors declare that no competing interests exist.
  5. Isabelle Georis

    Institut de Recherches Microbiologiques Jean-Marie Wiame, Anderlecht, Belgium
    Competing interests
    The authors declare that no competing interests exist.
  6. Bruno Andre

    IBMM - Molecular Physiology of the Cell, Université Libre de Bruxelles (ULB), Gosselies, Belgium
    For correspondence
    Bruno.Andre@ulb.ac.be
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7683-9150

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.

Metrics

  • 3,656
    views
  • 703
    downloads
  • 34
    citations

Views, downloads and citations are aggregated across all versions of this paper published by eLife.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Open citations (links to open the citations from this article in various online reference manager services)

Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)

  1. Elie Saliba
  2. Minoas Evangelinos
  3. Christos Gournas
  4. Florent Corrillon
  5. Isabelle Georis
  6. Bruno Andre
(2018)
The yeast H+-ATPase Pma1 promotes Rag/Gtr-dependent TORC1 activation in response to H+-coupled nutrient uptake
eLife 7:e31981.
https://doi.org/10.7554/eLife.31981

Share this article

https://doi.org/10.7554/eLife.31981

Further reading

    1. Cell Biology
    2. Developmental Biology
    Pavan K Nayak, Arul Subramanian, Thomas F Schilling
    Research Article Updated

    Mechanical forces play a critical role in tendon development and function, influencing cell behavior through mechanotransduction signaling pathways and subsequent extracellular matrix (ECM) remodeling. Here, we investigate the molecular mechanisms by which tenocytes in developing zebrafish embryos respond to muscle contraction forces during the onset of swimming and cranial muscle activity. Using genome-wide bulk RNA sequencing of FAC-sorted tenocytes we identify novel tenocyte markers and genes involved in tendon mechanotransduction. Embryonic tendons show dramatic changes in expression of matrix remodeling associated 5b (mxra5b), matrilin 1 (matn1), and the transcription factor kruppel-like factor 2a (klf2a), as muscles start to contract. Using embryos paralyzed either by loss of muscle contractility or neuromuscular stimulation we confirm that muscle contractile forces influence the spatial and temporal expression patterns of all three genes. Quantification of these gene expression changes across tenocytes at multiple tendon entheses and myotendinous junctions reveals that their responses depend on force intensity, duration, and tissue stiffness. These force-dependent feedback mechanisms in tendons, particularly in the ECM, have important implications for improved treatments of tendon injuries and atrophy.

    1. Cancer Biology
    2. Cell Biology
    Ida Marie Boisen, Nadia Krarup Knudsen ... Martin Blomberg Jensen
    Research Article

    Testicular microcalcifications consist of hydroxyapatite and have been associated with an increased risk of testicular germ cell tumors (TGCTs) but are also found in benign cases such as loss-of-function variants in the phosphate transporter SLC34A2. Here, we show that fibroblast growth factor 23 (FGF23), a regulator of phosphate homeostasis, is expressed in testicular germ cell neoplasia in situ (GCNIS), embryonal carcinoma (EC), and human embryonic stem cells. FGF23 is not glycosylated in TGCTs and therefore cleaved into a C-terminal fragment which competitively antagonizes full-length FGF23. Here, Fgf23 knockout mice presented with marked calcifications in the epididymis, spermatogenic arrest, and focally germ cells expressing the osteoblast marker Osteocalcin (gene name: Bglap, protein name). Moreover, the frequent testicular microcalcifications in mice with no functional androgen receptor and lack of circulating gonadotropins are associated with lower Slc34a2 and higher Bglap/Slc34a1 (protein name: NPT2a) expression compared with wild-type mice. In accordance, human testicular specimens with microcalcifications also have lower SLC34A2 and a subpopulation of germ cells express phosphate transporter NPT2a, Osteocalcin, and RUNX2 highlighting aberrant local phosphate handling and expression of bone-specific proteins. Mineral disturbance in vitro using calcium or phosphate treatment induced deposition of calcium phosphate in a spermatogonial cell line and this effect was fully rescued by the mineralization inhibitor pyrophosphate. In conclusion, testicular microcalcifications arise secondary to local alterations in mineral homeostasis, which in combination with impaired Sertoli cell function and reduced levels of mineralization inhibitors due to high alkaline phosphatase activity in GCNIS and TGCTs facilitate osteogenic-like differentiation of testicular cells and deposition of hydroxyapatite.