Interactions between nuclear genes and a foreign mitochondrial genome in the redbelly dace Chrosomus eos.
Given the coevolution process occurring between nuclear and mitochondrial genomes, the effects of introgressive hybridization remain puzzling. In this study, we take advantage of the natural co-occurrence of two biotypes bearing a similar nuclear genome (Chrosomus eos) but harbouring mitochondria from different species (wild type: C. eos; cybrids: Chrosomus neogaeus) to determine the extent of phenotype changes linked to divergence in the mitochondrial genome. Changes were assessed through differences in gene expression, enzymatic activity, proteomic and swimming activity. Our data demonstrate that complex IV activity was significantly higher in cybrids compared to wild type. This difference could result from one variable amino acid on the COX3 mitochondrial subunit and/or from a tremendous change in the proteome. We also show that cybrids present a higher swimming performance than wild type. Ultimately, our results demonstrate that the absence of coevolution for a period of almost ten million years between nuclear and mitochondrial genomes does not appear to be necessarily deleterious but could even have beneficial effects. Indeed, the capture of foreign mitochondria could be an efficient way to circumvent the selection process of genomic coevolution, allowing the rapid accumulation of new mutations in C. eos cybrids.
Department of Biological Sciences, Université de Montréal, C.P. 6128, succ. Centre-Ville, Montréal, QC H3C 3J7, Canada. Electronic address: leo.deremiens@umontreal.ca.
Léo
L
Deremiens
Department of Biological Sciences, Université de Montréal, C.P. 6128, succ. Centre-Ville, Montréal, QC H3C 3J7, Canada.
Logan
L
Schwartz
Department of Biological Sciences, Université de Montréal, C.P. 6128, succ. Centre-Ville, Montréal, QC H3C 3J7, Canada.
Annie
A
Angers
Department of Environmental Sciences, Université du Québec à Trois-Rivières, C.P. 500, Trois-Rivières, QC G9A 5H7, Canada.
Hélène
H
Glémet
Department of Biological Sciences, Université de Montréal, C.P. 6128, succ. Centre-Ville, Montréal, QC H3C 3J7, Canada.
Bernard
B
Angers
D000818:Animals; D002467:Cell Nucleus / Q000235:genetics* / Q000378:metabolism; D003530:Cyprinidae / Q000235:genetics* / Q000378:metabolism; D004579:Electron Transport / Q000235:genetics; D004789:Enzyme Activation; D015870:Gene Expression; D050259:Genes, Mitochondrial; D016678:Genome; D005838:Genotype; D006824:Hybridization, Genetic; D010641:Phenotype; D020543:Proteome / Q000378:metabolism; D013550:Swimming
D020543:Proteome
Critical swimming speed; Cybrid; Enzymatic activity; Mitochondria; Proteome