Meeting Abstract

75.5  Tuesday, Jan. 6  Genetic modulation of energy metabolism in birds through mitochondrial function TIELEMAN, B.I.*; VERSTEEGH, M.A.; FRIES, A.; HELM, B.; DINGEMANSE, N.J.; GIBBS, H.L.; WILLIAMS, J.B.; University of Groningen; University of Groningen; Ohio State University; Max Planck Institute for Ornithology; University of Groningen; Ohio State University; Ohio State University B.I.Tieleman@rug.nl

The genetic mechanisms that determine energy expenditure in animals have largely remained unstudied despite their central importance for the evolution of physiological variation. We used quantitative genetics to confirm that both mass-specific and whole-organism BMR were heritable in a captive-bred population of Stonechats (Saxicola torquata spp.) founded on birds from three wild populations that differed in basal metabolic rate (BMR). Our results suggest that BMR is at least partially under genetic control by multiple unknown genes. We then tested for a genetic effect on BMR based on mitochondrial-nuclear coadaptation using hybrids between ancestral populations with high and low BMR, with different parental configurations within each combination of populations. Hybrids with different parental configurations have on average identical mixtures of nuclear DNA, but differ in mitochondrial DNA because it is inherited from the mother only. Differences in mass-specific BMR between hybrids with different parental configurations showed that the match between mitochondrial and nuclear DNA had consequences for metabolic rate. Our findings implicate mitochondrial function as important regulator of energy metabolism. In combination with the substantial heritabilities of metabolic rate, and corroborated by genetic differences in the mitochondrial genome, these results set the stage for further investigations of a genetic control mechanism involving both mitochondrial and nuclear genes determining metabolic rate at the whole-organism level.