Effects of mitonuclear combination and thermal acclimation on the energetic phenotype

Abstract

Activity of the oxidative phosphorylation complexes rely on intimately associated subunits encoded by the mitochondrial and nuclear genomes. Given the key role of this system in adenosine triphosphate production, genes from both genomes must coevolve. A combination of northern redbelly dace (Chrosomus eos) or finescale dace (C. neogaeus) mitochondrial genome with a C. eos nuclear genome allows for a close examination of a naturally occurring disruption of mitonuclear coevolution. We, therefore, investigated the combined effect of mitonuclear genotypes, acclimation, and temperature on the activity of enzymes linked with the energy metabolism in a sympatric population of wild type and cybrid. As expected, the activity of the nuclear‐encoded citrate synthase was only influenced by temperature while the cytochrome c oxidase (composed of nuclear and mitochondrial subunits from wild type and cybrid individuals) responded differently to temperature. This study provides clear evidence of the extent by which mitonuclear coadaptation could influence aerobic metabolism.

Assessing the role of mitonuclear interactions on mitochondrial function and organismal fitness in naturalDrosophilapopulations

“…providing better adaptation to the environment), admixture may also unmask mitonuclear incompatibilities and manifest as decrease in life-history trait expression. There are examples of detrimental mitonuclear interactions impacting all aspects of individual fitness in yeast (Lee et al 2008 Chapdelaine et al 2020). However, most of the studies to date have focused on laboratory crosses between inbred populations, or interspecific crosses between geographically distant species, making the results difficult to translate to real-world population ecology.…”