Insect endosymbiont proliferation is limited by lipid availability

  1. Jeremy K Herren
  2. Juan C Paredes
  3. Fanny Schüpfer
  4. Karim Arafah
  5. Philippe Bulet
  6. Bruno Lemaitre  Is a corresponding author
  1. School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Switzerland
  2. Platform BioPark Archamps, France

Abstract

Spiroplasma poulsonii is a maternally transmitted bacterial endosymbiont that is naturally associated with Drosophila melanogaster. S. poulsonii resides extracellularly in the hemolymph, where it must acquire metabolites to sustain proliferation. In this study, we find that Spiroplasma proliferation specifically depletes host hemolymph diacylglyceride, the major lipid class transported by the lipoprotein, Lpp. RNAi-mediated knockdown of Lpp expression, which reduces the amount of circulating lipids, inhibits Spiroplasma proliferation demonstrating that bacterial proliferation requires hemolymph-lipids. Altogether, our study shows that an insect endosymbiont acquires specific lipidic metabolites from the transport lipoproteins in the hemolymph of its host. In addition, we show that the proliferation of this endosymbiont is limited by the availability of hemolymph lipids. This feature could limit endosymbiont over-proliferation under conditions of host nutrient limitation as lipid availability is strongly influenced by the nutritional state.

Article and author information

Author details

  1. Jeremy K Herren

    School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  2. Juan C Paredes

    School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  3. Fanny Schüpfer

    School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  4. Karim Arafah

    Platform BioPark Archamps, Saint Julien en Genevois, France
    Competing interests
    The authors declare that no competing interests exist.
  5. Philippe Bulet

    Platform BioPark Archamps, Saint Julien en Genevois, France
    Competing interests
    The authors declare that no competing interests exist.
  6. Bruno Lemaitre

    School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
    For correspondence
    bruno.lemaitre@epfl.ch
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Utpal Banerjee, University of California, Los Angeles, United States

Publication history

  1. Received: March 30, 2014
  2. Accepted: July 14, 2014
  3. Accepted Manuscript published: July 15, 2014 (version 1)
  4. Version of Record published: August 7, 2014 (version 2)

Copyright

© 2014, Herren 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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  1. Jeremy K Herren
  2. Juan C Paredes
  3. Fanny Schüpfer
  4. Karim Arafah
  5. Philippe Bulet
  6. Bruno Lemaitre
(2014)
Insect endosymbiont proliferation is limited by lipid availability
eLife 3:e02964.
https://doi.org/10.7554/eLife.02964

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