NDLI: Incidence du processus de vieillissement et des traits d'histoire de vie sur l'évolution de l'ADN mitochondrial chez les bivalves

Please wait, while we are loading the content...

Incidence du processus de vieillissement et des traits d'histoire de vie sur l'évolution de l'ADN mitochondrial chez les bivalves

Content Provider	Semantic Scholar
Author	Levivier, Aurore
Copyright Year	2016
Abstract	RESUME: Les bivalves sont de bons modeles biologiques pour l'etude du vieillissement cellulaire en raison de leurs grandes variations de longevites. L'objectif principal de la maitrise etait de comprendre le mode d'evolution de l'ADN mitochondrial (ADNmt) en lien avec le vieillissement cellulaire chez les bivalves. Pour repondre a cet objectif, deux etudes ont ete realisees. La premiere etude a permis de decrire les genomes mitochondriaux de neuf especes de la sous-classe des Heterodonta, de reconstituer la phylogenie des Heterodonta et d'etudier la repartition genetique de l'espece Arctica islandica. La deuxieme etude a permis d'etudier le mode d'evolution de l'ADNmt par rapport a trois traits d'histoire de vie (longevite, temps de generation et temperature maximale letale). La composition des genomes mitochondriaux des neuf especes d'Heterodonta correspond a celle retrouvee generalement chez les animaux : 13 genes codant pour les proteines, 2 genes ribonucleiques ribosomiques et 22 genes ribonucleiques de transfert ; meme si quelques particularites propres aux bivalves ont ete observees (duplication du gene COX2, addition de genes tRNA-Met, absence du gene ATP8 et configuration du gene CYTB en deux cadres de lecture). Les phylogenies des Heterodonta realisees a partir de la concatenation des sequences nucleotidiques de 12 genes mitochondriaux codant pour les proteines ont permis de confirmer les precedentes phylogenies et d'etablir une relation de parente solide entre les especes Arctica islandica et Corbicula fluminea. L'etude sur la repartition genetique de l'espece Arctica islandica montre que la population du golfe du Saint-Laurent est genetiquement plus proche de la population de la mer Baltique, que des populations de la mer du Nord et d'Islande. Le vieillissement, represente par la longevite dans la deuxieme etude, est explique a 68% par le temps de generation et a 22% par la temperature. Le taux de substitution synonyme est explique en partie (entre 9 et 30%) par la longevite. Les autres traits d'histoire de vie etudies (temps de generation et temperature maximale letale) n'influencent pas l'evolution de l'ADNmt chez les bivalves. Nous presentons ici, la premiere etude sur l'impacte de la longevite sur le mode d'evolution de l'ADNmt chez des invertebres. - Mot(s) cle(s) en francais : vieillissement, genome mitochondrial, bivalve, phylogenie Bayesienne, evolution des traits d'histoire de vie, taux de substitution, Arctica islandica. - ABSTRACT: Bivalves are good model for studying evolutionary processes related to aging as they exhibit great variations in longevities among species. The aim of this Master was to understand how mitochondrial DNA (mtDNA) has evolved in relation to aging in bivalves. Two studies were performed to answer this question. The first chapter examines the description of the mitochondrial genomes of nine species of the subclass Heterodonta, provides a new Heterodonta phylogeny, and examines intraspecific variation in Arctica islandica using the full mitochondria genomes. The second study focus on the evolution of mtDNA relative to three life-history traits (longevity, generation time, and maximum lethal temperature). Mitochondrial genome cartography for the nine Heterodonta species corresponds to what is generally found in animals: 13 protein-coding genes, 2 ribosomal RNA genes and 22 transfer RNA genes. Some characters specific to bivalves were observed (duplication of COX2 gene, addition of tRNA-Met genes, lack of ATP8 gene and two reading frames for CYTB gene). Heterodonta phylogenies performed from the concatenation of 12 protein-coding genes nucleotide sequences confirmed previous phylogenies and established a strong relationship between the species Arctica islandica and Corbicula fluminea. Results on genetics repartition of Arctica islandica showed that the population from the Gulf of St. Lawrence was genetically closer to Baltic Sea population than to populations from the North Sea and Iceland. Aging, represented by longevity in the second chapter, was explained by generation time (68%) and by temperature (22%). The synonymous substitution rate is explained in part (between 9 and 30%) by longevity. Other life history traits studied (generation time and maximum lethal temperature) did not influence mtDNA evolution in bivalves. We present here, the first study on the evolution of mtDNA relative to longevity in invertebrates. - Mot(s) cle(s) en anglais : aging, mitochondrial genome, bivalve, Bayesian phylogeny, life-history evolution, substitution rates, Arctica islandica.
File Format	PDF HTM / HTML
Alternate Webpage(s)	http://semaphore.uqar.ca/1182/1/Aurore_Levivier_mars2016.pdf
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article

Central Library (ISO-9001:2015 Certified)
Indian Institute of Technology Kharagpur
Kharagpur, West Bengal, India | PIN - 721302

See location in the Map
03222 282435
Mail: support@ndl.gov.in

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in