Publications associées à Loss of reproductive parasitism following transfer of male-killing Wolbachia to Drosophila melanogaster and Drosophila simulans

Reproductive isolation arises during laboratory adaptation to a novel hot environment

Background: Reproductive isolation can result from adaptive processes (e.g., ecological speciation and mutation-order speciation) or stochastic processes such as "system drift" model. Ecological speciation predicts barriers to gene flow between populations ...

BMC2024

Energy-harnessing problem solving of primordial life: Modeling the emergence of catalytic host-nested parasite life cycles

Christian Iseli

All life forms on earth ultimately descended from a primordial population dubbed the last universal common ancestor or LUCA via Darwinian evolution. Extant living systems share two salient functional features, a metabolism extracting and transforming energ ...

2023

Rapid molecular evolution of Spiroplasma symbionts of Drosophila

Bruno Lemaitre, Florent François Masson

Spiroplasma is a genus of Mollicutes whose members include plant pathogens, insect pathogens and endosymbionts of animals. Spiroplasma phenotypes have been repeatedly observed to be spontaneously lost in Drosophila cultures, and several studies have docume ...

2021

The role of immune effectors in controlling Drosophila-microbes interactions

Alice Marra

All live beings are in constant interaction with microorganisms that may be beneficial, deleterious or commensal. Insects in particular live in close contact with microorganisms. This is especially true for species, like the fruit fly Drosophila melanogast ...

EPFL2021

Transformation of the Drosophila Sex-Manipulative Endosymbiont Spiroplasma poulsonii and Persisting Hurdles for Functional Genetic Studies

Bruno Lemaitre, Florent François Masson, Chloé Christiane Laurence Jollivet

Insects are frequently infected by bacterial symbionts that greatly affect their physiology and ecology. Most of these endosymbionts are, however, barely tractable outside their native host, rendering functional genetics studies difficult or impossible. Sp ...

AMER SOC MICROBIOLOGY2020

Blind killing of both male and female Drosophila embryos by a natural variant of the endosymbiotic bacterium Spiroplasma poulsonii

Bruno Lemaitre, Juan Camilo Paredes Escobar, Mario Gonzalo Garcia Arraez, Samuel Rommelaere, Florent François Masson

Spiroplasma poulsonii is a vertically transmitted endosymbiont of Drosophila melanogaster that causes male-killing, that is the death of infected male embryos during embryogenesis. Here, we report a natural variant of S. poulsonii that is efficiently verti ...

WILEY2020

Sub-cellular imaging shows reduced photosynthetic carbon and increased nitrogen assimilation by the non-native endosymbiontDurusdinium trenchiiin the model cnidarian Aiptasia

Anders Meibom

Hosting different symbiont species can affect inter-partner nutritional fluxes within the cnidarian-dinoflagellate symbiosis. Using nanoscale secondary ion mass spectrometry (NanoSIMS), we measured the spatial incorporation of photosynthetically fixed(13)C ...

WILEY2020

Intracellular competition for nitrogen controls dinoflagellate population density in corals

Julia Marie Jeanne Yvonne Bodin, Anders Meibom, Stéphane Laurent Escrig, Maria-Evangelia Giovani, Thomas Krüger, Maoz Fine

The density of dinoflagellate microalgae in the tissue of symbiotic corals is an important determinant for health and productivity of the coral animal. Yet, the specific mechanism for their regulation and the consequence for coral nutrition are insufficien ...

ROYAL SOC2020

Commensal Gut Bacteria Buffer the Impact of Host Genetic Variants on Drosophila Developmental Traits under Nutritional Stress

Michael Vincent Frochaux, Bart Deplancke, Maroun Bou Sleiman, Virginie Sandra Braman, Maria Litovchenko

Eukaryotic genomes encode several buffering mechanisms that robustly maintain invariant phenotypic outcome despite fluctuating environmental conditions. Here we show that the Drosophila gut-associated commensals, represented by a single facultative symbion ...

2019

Functional analysis of RIP toxins from the Drosophila endosymbiont Spiroplasma poulsonii

Bruno Lemaitre, Juan Camilo Paredes Escobar, Mario Gonzalo Garcia Arraez, Florent François Masson

BackgroundInsects frequently live in close relationship with symbiotic bacteria that carry out beneficial functions for their host, like protection against parasites and viruses. However, in some cases, the mutualistic nature of such associations is put in ...

2019

Weevil pgrp-lb prevents endosymbiont TCT dissemination and chronic host systemic immune activation

Florent François Masson, João Pedro Alves Da Silva

Long-term intracellular symbiosis (or endosymbiosis) is widely distributed across invertebrates and is recognized as a major driving force in evolution. However, the maintenance of immune homeostasis in organisms chronically infected with mutualistic bacte ...

National Academy of Sciences2019

Controlling strategies to maximize reliability of integrated photo-electrochemical devices exposed to realistic disturbances

Sophia Haussener, Saurabh Yuvraj Tembhurne

We numerically investigate the conversion of solar energy into chemical energy by integrated photo-electrochemical (IPEC) devices and assess their response to time-dependent changes in the boundary conditions and the material properties. We focus on a devi ...

RSC2019

Non-crystalline tetravalent uranium species in the subsurface: formation and stability

Luca Loreggian

Uranium (U) contamination of ground and surface waters poses an acute hazard on the ecosystem and human health. Since the discovery of microbial U(VI) reduction, U bioremediation has been explored as a promising and cost-effective method compared to tradit ...

EPFL2019

Common and unique strategies of male killing evolved in two distinct Drosophila symbionts

Bruno Lemaitre, Toshiyuki Harumoto

Male killing is a selfish reproductive manipulation caused by symbiotic bacteria, where male offspring of infected hosts are selectively killed. The underlying mechanisms and the process of their evolution are of great interest not only in terms of fundame ...

2018

The double-edged toxins : how Spiroplasma Ribosome-Inactivating Proteins affect Drosophila melanogaster life history traits

Mario Gonzalo Garcia Arraez

Many insect species are associated with endosymbiotic bacteria which have the particularity of living within host tissues. Endosymbionts benefit from this stable and nutritious environment, while providing ecological advantages to their host, such as prote ...

EPFL2018

Male-killing toxin in a bacterial symbiont of Drosophila

Bruno Lemaitre, Toshiyuki Harumoto

Several lineages of symbiotic bacteria in insects selfishly manipulate host reproduction to spread in a population 1 , often by distorting host sex ratios. Spiroplasma poulsonii2,3 is a helical and motile, Gram-positive symbiotic bacterium that resides in ...

2018

In Vitro Culture of the Insect Endosymbiont Spiroplasma poulsonii Highlights Bacterial Genes Involved in Host-Symbiont Interaction

Bruno Lemaitre, Fanny Schüpfer, Mario Gonzalo Garcia Arraez, Florent François Masson

Endosymbiotic bacteria associated with eukaryotic hosts are omnipresent in nature, particularly in insects. Studying the bacterial side of host-symbiont interactions is, however, often limited by the unculturability and genetic intractability of the symbio ...

2018

Signatures of selection and environmental adaptation across the goat genome post-domestication

Stéphane Joost, Estelle Rochat

Background: Since goat was domesticated 10,000 years ago, many factors have contributed to the differentiation of goat breeds and these are classified mainly into two types: (i) adaptation to different breeding systems and/or purposes and (ii) adaptation t ...

2018

The melanization reaction in Drosophila: More than black or white

Jan Paul Dudzic

The melanization reaction is a rapid and important immune mechanism in arthropods. It results in the production of melanin at the site of injury and around invading microbes. The enzymes responsible for melanogenesis are phenoloxidases (PO), which catalyze ...

EPFL2018

Vibrio coralliilyticus infection triggers a behavioural response and perturbs nutritional exchange and tissue integrity in a symbiotic coral

Anders Meibom, Louise Helene Soegaard Jensen, Emma Mary Gibbin

Under homoeostatic conditions, the relationship between the coralPocillopora damicornisandVibrio coralliilyticusiscommensal. An increase in temperature, or in the abundance ofV. coralliilyticus, can turn this association pathogenic,causing tissue lysis, ex ...

2019