Bettinazzi 2022 Abstract Bioblast
P01. Bettinazzi Stefano, Camus F, Dowling DK, Lane N (2022) Linking the mitonuclear genotype with mitochondrial function and organismal fitness. Bioblast 2022: BEC Inaugural Conference. In: https://doi.org/10.26124/bec:2022-0001 |
Link: Bioblast 2022: BEC Inaugural Conference
Bettinazzi Stefano, Camus F, Dowling DK, Lane Nick (2022)
Event: Bioblast 2022
Despite playing a key role in energy metabolism, mitochondria are uniquely exposed to perturbation because their functions depend on the correct interaction between two distinct genomes, the mitochondrial and the nuclear DNA. Even mild incompatibilities between the two genomes could impact mitochondrial functions with downstream repercussions on individual fitness. Climate change predictions estimate an increase in temperature and its variability, changes in food web structures, but also in the distribution of populations. Events that may generate mitonuclear mismatches (e.g. hybridization between separate populations) are therefore expected to increase in frequency following the shifts in thermal niches. In addition, temperature and dietary regimes are well-known metabolic stressors whose variation can potentially exacerbate mitonuclear incompatibilities. The aim of this research was to test how far mild mitonuclear variations, of the kind that could be found in natural populations following introgression in shifting niches, might affect organismal fitness.
I employed four experimental lines of the fruitfly Drosophila melanogaster, characterized by mitonuclear match or mismatch, to investigate the impact of mitonuclear genotype over a wide array of phenotypic traits, including mitochondrial functions, reactive oxygen species metabolism and life-history traits.
Results indicate a general trade-off between bioenergetic capacity and fecundity in mitonuclear mismatched lines, most prominently in females than males. Cybrids tend to have a higher OXPHOS activity compared to the matched parental populations, as well as generally lower H2O2 efflux. The high mitochondrial respiration rate also links with a trend of higher locomotor activity, but with lower fecundity parameters. Finally, differences in thermal tolerance also exist, but link solely to the nuclear component, and not to the mitonuclear combination. Overall, results suggest that mitonuclear interactions might impact organismal fitness in an unpredictable way, potentially influencing local adaptation in a mutating world.
β’ Keywords: Mitochondria, Mitonuclear coevolution, Drosophila, Fitness, Climate change
β’ O2k-Network Lab: UK London Lane N
Affiliations
- Bettinazzi S1, Camus F1, Dowling DK2, Lane N1
- University College London, UK - [email protected]
- Monash University, AU
- Bettinazzi S1, Camus F1, Dowling DK2, Lane N1
List of abbreviations, terms and definitions - MitoPedia
Labels: MiParea: Respiration, mtDNA;mt-genetics, nDNA;cell genetics, Comparative MiP;environmental MiP
Regulation: Temperature
Coupling state: OXPHOS
HRR: Oxygraph-2k Event: Poster