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CIG BBQ 2019 : Thursday, July 11 at 5:00pm in Vidy

Thursday, July 11th, 5:00 p.m. at Vidy beach

Georgia, Eric, Valentine and Stefanie, our CIG Barbecue Team are organizing the annual summer BBQ in the Vidy park on Thursday July 11, 2019 starting from 5 p.m.  

Please sign up now to make sure they count you in https://doodle.com/poll/ptrsxftnd9928wyi

A big thank you to the organizers

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Curr Biol.: co-auth.: C.Dessimoz

 2019 May 16. pii: S0960-9822(19)30407-5. doi: 10.1016/j.cub.2019.04.009. [Epub ahead of print]

Mitigating Anticipated Effects of Systematic Errors Supports Sister-Group Relationship between Xenacoelomorpha and Ambulacraria.

Abstract

Xenoturbella and the acoelomorph worms (Xenacoelomorpha) are simple marine animals with controversial affinities. They have been placed as the sister group of all other bilaterian animals (Nephrozoa hypothesis), implying their simplicity is an ancient characteristic [1, 2]; alternatively, they have been linked to the complex Ambulacraria (echinoderms and hemichordates) in a clade called the Xenambulacraria [3-5], suggesting their simplicity evolved by reduction from a complex ancestor. The difficulty resolving this problem implies the phylogenetic signal supporting the correct solution is weak and affected by inadequate modeling, creating a misleading non-phylogenetic signal. The idea that the Nephrozoa hypothesis might be an artifact is prompted by the faster molecular evolutionary rate observed within the Acoelomorpha. Unequal rates of evolution are known to result in the systematic artifact of long branch attraction, which would be predicted to result in an attraction between long-branch acoelomorphs and the outgroup, pulling them toward the root [6]. Other biases inadequately accommodated by the models used can also have strong effects, exacerbated in the context of short internal branches and long terminal branches [7]. We have assembled a large and informative dataset to address this problem. Analyses designed to reduce or to emphasize misleading signals show the Nephrozoa hypothesis is supported under conditions expected to exacerbate errors, and the Xenambulacraria hypothesis is preferred in conditions designed to reduce errors. Our reanalyses of two other recently published datasets [1, 2] produce the same result. We conclude that the Xenacoelomorpha are simplified relatives of the Ambulacraria.

PMID: 31104936

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Int J Mol Sci.: auth.: W.Wahli

 2018 Jul 28;19(8). pii: E2210. doi: 10.3390/ijms19082210.

Enteric Microbiota⁻Gut⁻Brain Axis from the Perspective of Nuclear Receptors.

Abstract

Nuclear receptors (NRs) play a key role in regulating virtually all body functions, thus maintaining a healthy operating body with all its complex systems. Recently, gut microbiota emerged as major factor contributing to the health of the whole organism. Enteric bacteria have multiple ways to influence their host and several of them involve communication with the brain. Mounting evidence of cooperation between gut flora and NRs is already available. However, the full potential of the microbiota interconnection with NRs remains to be uncovered. Herewith, we present the current state of knowledge on the multifaceted roles of NRs in the enteric microbiota⁻gut⁻brain axis.

KEYWORDS:

metabolism; microbiota; nuclear receptors; xenobiotics

PMID: 30060580

 

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MBio.: co-auth.: GTF

 2018 Mar 20;9(2). pii: e00024-18. doi: 10.1128/mBio.00024-18.

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

Abstract

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 symbionts. Spiroplasma poulsoniiis a maternally transmitted bacterial endosymbiont that is naturally associated with several Drosophila species. S. poulsonii strongly affects its host’s physiology, for example by causing male killing or by protecting it against various parasites. Despite intense work on this model since the 1950s, attempts to cultivate endosymbiotic Spiroplasma in vitro have failed so far. Here, we developed a method to sustain the in vitro culture of S. poulsonii by optimizing a commercially accessible medium. We also provide a complete genome assembly, including the first sequence of a natural plasmid of an endosymbiotic Spiroplasma species. Last, by comparing the transcriptome of the in vitro culture to the transcriptome of bacteria extracted from the host, we identified genes putatively involved in host-symbiont interactions. This work provides new opportunities to study the physiology of endosymbiotic Spiroplasma and paves the way to dissect insect-endosymbiont interactions with two genetically tractable partners.IMPORTANCE The discovery of insect bacterial endosymbionts (maternally transmitted bacteria) has revolutionized the study of insects, suggesting novel strategies for their control. Most endosymbionts are strongly dependent on their host to survive, making them uncultivable in artificial systems and genetically intractable. Spiroplasma poulsonii is an endosymbiont of Drosophila that affects host metabolism, reproduction, and defense against parasites. By providing the first reliable culture medium that allows a long-lasting in vitro culture of Spiroplasma and by elucidating its complete genome, this work lays the foundation for the development of genetic engineering tools to dissect endosymbiosis with two partners amenable to molecular study. Furthermore, the optimization method that we describe can be used on other yet uncultivable symbionts, opening new technical opportunities in the field of host-microbes interactions.

KEYWORDS:

Spiroplasma; endosymbiosis; host-symbiont interaction

PMID: 29559567

 

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Organization of the sinks’ cleaning in the Génopode (2018)

Organization of the sinks’ cleaning in the Génopode – 2018

Groups members should make sure all the sinks in their labs are emptied on these dates, in order for the cleaning staff to proceed with their cleaning.

Link to the complete cleaning planing: http://unil.ch/cig/home/menuguid/faq/cleaning-and-waste-disposal.html

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Seminar on November 24th, 2017 : Ana Lopez-Vazquez

Capture d’écran 2017-11-14 à 18.14.51