title: Functional conservatism among Drosophila simulans flies experiencing different thermal regimes and mitochondrial DNA introgression.
abstract: Drosophila simulans possesses three different mitochondrial haplotypes (siI, II and III) that are nonrandomly geographically subdivided with a 3% interhaplogroup variation. The aim of this study was to determine whether perturbation of mitochondrial metabolism and ROS management by temperature variation and mtDNA introgression would influence the development of aerobic capacity and the intensity of oxidative stress in D. simulans at different ages. Environmental temperature divergences during development had few impacts on metabolic capacities. Our data suggested strong functional conservatism of mitochondrial haplotypes between the D. simulans lines studied. This conservatism was expressed by the low divergences in either mitochondrial or ROS buffering enzyme activities, or even markers of ROS damage even after disruption of coevolved genomes. Disruption of coevolved mitochondrial and nuclear genomes through mtDNA introgression induced no clear divergence on metabolic phenotype at any state of development. Reduction of cytochrome c oxidase activity that was observed after introgression of one mitochondrial haplotype will require further investigation to delineate whether it is associated with any modification of mito-nuclear interactions.
authors.affiliation: Laboratoire de biologie intégrative, Département de Biologie, Université du Québec à Rimouski, Rimouski, Québec, Canada.
authors.forename: Etienne Hébert
authors.initials: EH
authors.lastname: Chatelain
authors.forename: Nicolas
authors.initials: N
authors.lastname: Pichaud
authors.forename: J William O
authors.initials: JW
authors.lastname: Ballard
authors.forename: Robert M
authors.initials: RM
authors.lastname: Tanguay
authors.forename: Geneviève
authors.initials: G
authors.lastname: Morrow
authors.forename: Pierre U
authors.initials: PU
authors.lastname: Blier
mesh_terms: D000818:Animals; D015415:Biomarkers; D002952:Citric Acid Cycle; D004272:DNA, Mitochondrial / Q000235:genetics*; D004330:Drosophila / Q000145:classification / Q000235:genetics* / Q000502:physiology*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D045222:Electron Transport Chain Complex Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation / Q000502:physiology*; D008297:Male; D018384:Oxidative Stress; D013696:Temperature
chemical_list: D015415:Biomarkers; D004272:DNA, Mitochondrial; D029721:Drosophila Proteins; D045222:Electron Transport Chain Complex Proteins