Category: Papers by CGEB labs

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Archaea.
Curr Biol. 2015 Oct 5;25(19):R851-5
Authors: Eme L, Doolittle WF
Abstract
A headline on the front page of the New York Times for November 3, 1977, read “Scientists Discover …

Endosymbiosis and Eukaryotic Cell Evolution.

Curr Biol. 2015 Oct 5;25(19):R911-21

Authors: Archibald JM

Abstract
Understanding the evolution of eukaryotic cellular complexity is one of the grand challenges of modern biology. It has now been firmly established that mitochondria and plastids, the classical membrane-bound organelles of eukaryotic cells, evolved from bacteria by endosymbiosis. In the case of mitochondria, evidence points very clearly to an endosymbiont of α-proteobacterial ancestry. The precise nature of the host cell that partnered with this endosymbiont is, however, very much an open question. And while the host for the cyanobacterial progenitor of the plastid was undoubtedly a fully-fledged eukaryote, how – and how often – plastids moved from one eukaryote to another during algal diversification is vigorously debated. In this article I frame modern views on endosymbiotic theory in a historical context, highlighting the transformative role DNA sequencing played in solving early problems in eukaryotic cell evolution, and posing key unanswered questions emerging from the age of comparative genomics.

PMID: 26439354 [PubMed – in process]

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The Semantics of the Modular Architecture of Protein Structures.
Curr Protein Pept Sci. 2015 Sep 22;
Authors: Hleap JS, Blouin C
Abstract
Protein structures can be conceptualized as …

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Projection scenarios of body mass index (2013-2030) for Public Health Planning in Quebec.
BMC Public Health. 2014;14:996
Authors: Lo E, Hamel D, Jen Y, Lamontagne P, Martel S, Steensma C, Blouin C…

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Phylogenomics Reveals Convergent Evolution of Lifestyles in Close Relatives of Animals and Fungi.

Curr Biol. 2015 Sep 9;

Authors: Torruella G, de Mendoza A, Grau-Bové X, Antó M, Chaplin MA, Del Campo J, Eme L, Pérez-Cordón G, Whipps CM, Nichols KM, Paley R, Roger AJ, Sitjà-Bobadilla A, Donachie S, Ruiz-Trillo I

Abstract
The Opisthokonta are a eukaryotic supergroup divided in two main lineages: animals and related protistan taxa, and fungi and their allies [1, 2]. There is a great diversity of lifestyles and morphologies among unicellular opisthokonts, from free-living phagotrophic flagellated bacterivores and filopodiated amoebas to cell-walled osmotrophic parasites and saprotrophs. However, these characteristics do not group into monophyletic assemblages, suggesting rampant convergent evolution within Opisthokonta. To test this hypothesis, we assembled a new phylogenomic dataset via sequencing 12 new strains of protists. Phylogenetic relationships among opisthokonts revealed independent origins of filopodiated amoebas in two lineages, one related to fungi and the other to animals. Moreover, we observed that specialized osmotrophic lifestyles evolved independently in fungi and protistan relatives of animals, indicating convergent evolution. We therefore analyzed the evolution of two key fungal characters in Opisthokonta, the flagellum and chitin synthases. Comparative analyses of the flagellar toolkit showed a previously unnoticed flagellar apparatus in two close relatives of animals, the filasterean Ministeria vibrans and Corallochytrium limacisporum. This implies that at least four different opisthokont lineages secondarily underwent flagellar simplification. Analysis of the evolutionary history of chitin synthases revealed significant expansions in both animals and fungi, and also in the Ichthyosporea and C. limacisporum, a group of cell-walled animal relatives. This indicates that the last opisthokont common ancestor had a complex toolkit of chitin synthases that was differentially retained in extant lineages. Thus, our data provide evidence for convergent evolution of specialized lifestyles in close relatives of animals and fungi from a generalist ancestor.

PMID: 26365255 [PubMed – as supplied by publisher]

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Diversity and origins of anaerobic metabolism in mitochondria and related organelles.
Philos Trans R Soc Lond B Biol Sci. 2015 Sep 26;370(1678)
Authors: Stairs CW, Leger MM, Roger AJ
Abstrac…

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Eukaryotes first: how could that be?
Philos Trans R Soc Lond B Biol Sci. 2015 Sep 26;370(1678)
Authors: Mariscal C, Doolittle WF
Abstract
In the half century since the formulation of…

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Symbiosis becoming permanent: Survival of the luckiest.
Proc Natl Acad Sci U S A. 2015 Aug 18;112(33):10101-3
Authors: Keeling PJ, McCutcheon JP, Doolittle WF
PMID: 26283342 [PubMed – in p…

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Reply to Lane and Martin: Being and becoming eukaryotes.
Proc Natl Acad Sci U S A. 2015 Aug 17;
Authors: Booth A, Doolittle WF
PMID: 26283404 [PubMed – as supplied by publisher]

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Evolution: Gene transfer in complex cells.
Nature. 2015 Aug 27;524(7566):423-4
Authors: Archibald JM
PMID: 26287464 [PubMed – in process]