Landscape genomics: natural selection drives the evolution of mitogenome in penguins

• Main Authors: Ramos, Barbara, González-Acuña, Daniel, Loyola, David, Johnson, Warren, Parker, Patricia, Massaro, Melanie, Gisele Dantas, Miranda, Marcelo, Vianna, Juliana
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Figshare 2018
• Subjects: Biochemistry; Genetics; FOS Biological sciences; Evolutionary Biology; Ecology; Inorganic Chemistry; FOS Chemical sciences; 110309 Infectious Diseases; FOS Health sciences; Computational Biology; Galapagos; Antarc*; Antarctica; Pygoscelis adeliae
• Online Access: https://dx.doi.org/10.6084/m9.figshare.c.3978135.v1; https://figshare.com/collections/Landscape_genomics_natural_selection_drives_the_evolution_of_mitogenome_in_penguins/3978135/1

Abstract Background Mitochondria play a key role in the balance of energy and heat production, and therefore the mitochondrial genome is under natural selection by environmental temperature and food availability, since starvation can generate more efficient coupling of energy production. However, selection over mitochondrial DNA (mtDNA) genes has usually been evaluated at the population level. We sequenced by NGS 12 mitogenomes and with four published genomes, assessed genetic variation in ten penguin species distributed from the equator to Antarctica. Signatures of selection of 13 mitochondrial protein-coding genes were evaluated by comparing among species within and among genera (Spheniscus, Pygoscelis, Eudyptula, Eudyptes and Aptenodytes). The genetic data were correlated with environmental data obtained through remote sensing (sea surface temperature [SST], chlorophyll levels [Chl] and a combination of SST and Chl [COM]) through the distribution of these species. Results We identified the complete mtDNA genomes of several penguin species, including ND6 and 8 tRNAs on the light strand and 12 protein coding genes, 14 tRNAs and two rRNAs positioned on the heavy strand. The highest diversity was found in NADH dehydrogenase genes and the lowest in COX genes. The lowest evolutionary divergence among species was between Humboldt (Spheniscus humboldti) and Galapagos (S. mendiculus) penguins (0.004), while the highest was observed between little penguin (Eudyptula minor) and Adélie penguin (Pygoscelis adeliae) (0.097). We identified a signature of purifying selection (Ka/Ks