EntomoNews

The genome of Armadillidium vulgare (Crustacea, Isopoda) provides insights into sex chromosome evolution in the context of cytoplasmic sex determination

Mohamed Amine Chebbi Thomas Becking Bouziane Moumen Isabelle Giraud Clément Gilbert Jean Peccoud Richard Cordaux
Molecular Biology and Evolution, 22 January 2019

 

 

[via] Richard Cordaux sur Twitter, 23.01.2019 :

"Very proud to announce the publication of the genome of the #isopod crustacean Armadillidium vulgare, a model for the study of symbiosis with feminizing #Wolbachia and the evolution of sex determination. 1.7 Gb - BUSCO v3 =92% - 68% repeats! ..."

https://twitter.com/RichardCordaux/status/1087995784040247297

 

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Une précédente étude :

 

Thomas Becking, Isabelle Giraud, Maryline Raimond, Bouziane Moumen, Christopher Chandler, Richard Cordaux & Clément Gilbert

 

• Diversity and evolution of sex determination systems in terrestrial isopods | Scientific Reports, 24.04.2017 https://www.nature.com/articles/s41598-017-01195-4

Les arthropodes peuvent avoir leur reproduction perturbée par des microorganismes intracellulaires qui se transmettent de génération en génération. L’un des plus répandus de ces parasites du sexe est la bactérie du genre Wolbachia, célèbre pour les effets qu’elle induit sur ses hôtes. Chez les cloportes (crustacés isopodes), cette bactérie favorise l’apparition de descendants femelles. Dans l’étude publiée dans Scientific Reports, Jessica Dittmer et Didier Bouchon du laboratoire Ecologie et Biologie des Interactions (Université de Poitiers / CNRS) montrent que la présence de Wolbachia influence la composition du microbiote des hôtes et ce, quel que soit leur environnement. Cette étude souligne l’importance des interactions compétitives entre microorganismes au sein du microbiome.

 

CNRS - Institut écologie et environnement, 04.05.2018

 

• Feminizing Wolbachia influence microbiota composition in the terrestrial isopod Armadillidium vulgare | Scientific Reports, 03.05.2018 https://www.nature.com/articles/s41598-018-25450-4

 

[Image] Microscopie électronique de cellules de la chaine nerveuse du cloporte commun Armadillidium vulgare : à gauche sont visibles deux bactéries Wolbachia entourées de mitochondries. Crédit photographique : Maryline RAIMOND 

Des chercheurs de l'UE ont étudié l'homme, les animaux, les plantes et même les champignons pour comprendre comment les évènements au début de la vie influencent le processus de vieillissement.

 

La vie avant la mort : l'épigénétique du vieillissement. Commission européenne, CORDIS, Service Projets et résultats. Pays-Bas, 23.12.2016

 

→ Final Report Summary - IDEAL (Integrated research on DEvelopmental determinants of Aging and Longevity)
http://cordis.europa.eu/result/rcn/187878_en.html

 

"... Biological determinants of sex differences in ageing invertebrates (insects and worms)

In developed countries, men die of age-related pathologies on average some 5-6 years earlier than women although women spend on average more years in disability. Moreover, the incidence of many individual age-related diseases is different between men and women. Although for humans these sex differences have not always been present, in animal models sex differences have been consistently observed.

Many differences between male and female originate from differences in developmental processes occurring, particularly in utero and during puberty. Thus, the origins of sex differences in ageing pathology likely originate in early sex determinative developmental processes. One objective of research in WP 3 of IDEAL has been to better understand how sex determination specifies sex differences in ageing and late-life health. This research has focused on tractable model organisms (the nematode C. elegans and the fruit fly Drosophila)."

(...)

 

[Image] Home - IDEAL Ageing
http://www.ideal-ageing.eu/

 

La revue Atala publie un numéro spécial consacré à la Biologie Évolutive sous la direction de Louis Allano. Myriam Harry (LEGS) et Tatiana Giraud en collaboration avec Pierre-Henri Gouyon (ESE) ont écrit respectivement les chapitres "Cas d'espèces et espèce de cas : espèces et spéciation" et "Évolution du sexe, évolution des sexes".

Diverse selfish genetic elements have evolved the ability to manipulate reproduction to increase their transmission, and this can result in highly distorted sex ratios

 

• Genetics and Genomics of an Unusual Selfish Sex Ratio Distortion in an Insect, Current Biology, 15.11.2018

 

 

"Indeed, one of the major explanations for why sex determination systems are so dynamic is because they are shaped by ongoing coevolutionary arms races between sex-ratio-distorting elements and the rest of the genome [2].

 

Here, we use genetic crosses and genome analysis to describe an unusual sex ratio distortion with striking consequences on genome organization in a booklouse species, Liposcelis sp. (Insecta: Psocodea), in which two types of females coexist. Distorter females never produce sons but must mate with males (the sons of nondistorting females) to reproduce [3].

 

Although they are diploid and express the genes inherited from their fathers in somatic tissues, distorter females only ever transmit genes inherited from their mothers.

 

As a result, distorter females have unusual chimeric genomes, with distorter-restricted chromosomes diverging from their nondistorting counterparts and exhibiting features of a giant non-recombining sex chromosome.

 

The distorter-restricted genome has also acquired a gene from the bacterium Wolbachia, a well-known insect reproductive manipulator; we found that this gene has independently colonized the genomes of two other insect species with unusual reproductive systems, suggesting possible roles in sex ratio distortion in this remarkable genetic system."