The adaptive evolution of the mammalian mitochondrial genome

• Tipo: Artigo em Revista Científica Internacional
• Data: 2008

Autores

Rute R da Fonseca (Autor) Outra; Warren E Johnson (Autor) Outra; Stephen J O'Brien (Autor) Outra; Maria Joao Ramos (Autor) FCUP; Agostinho Antunes (Autor) Outra

Revista

Título: BMC Genomics

Vol. 9

Página Final: 119

ISSN: 1471-2164

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 274 Citações

Scopus - 281 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Ciências biológicas

Outras Informações

ID Authenticus: P-004-0XY

DOI: 10.1186/1471-2164-9-119

Abstract (EN): Background: The mitochondria produce up to 95% of a eukaryotic cell's energy through oxidative phosphorylation. The proteins involved in this vital process are under high functional constraints. However, metabolic requirements vary across species, potentially modifying selective pressures. We evaluate the adaptive evolution of 12 protein-coding mitochondrial genes in 41 placental mammalian species by assessing amino acid sequence variation and exploring the functional implications of observed variation in secondary and tertiary protein structures. Results: Wide variation in the properties of amino acids were observed at functionally important regions of cytochrome b in species with more-specialized metabolic requirements (such as adaptation to low energy diet or large body size, such as in elephant, dugong, sloth, and pangolin, and adaptation to unusual oxygen requirements, for example diving in cetaceans, flying in bats, and living at high altitudes in alpacas). Signatures of adaptive variation in the NADH dehydrogenase complex were restricted to the loop regions of the transmembrane units which likely function as protons pumps. Evidence of adaptive variation in the cytochrome c oxidase complex was observed mostly at the interface between the mitochondrial and nuclear-encoded subunits, perhaps evidence of co-evolution. The ATP8 subunit, which has an important role in the assembly of F-0, exhibited the highest signal of adaptive variation. ATP6, which has an essential role in rotor performance, showed a high adaptive variation in predicted loop areas. Conclusion: Our study provides insight into the adaptive evolution of the mtDNA genome in mammals and its implications for the molecular mechanism of oxidative phosphorylation. We present a framework for future experimental characterization of the impact of specific mutations in the function, physiology, and interactions of the mtDNA encoded proteins involved in oxidative phosphorylation.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 22