Evolution of Mitochondrial Genomes

Mitochondria are tiny organelles inside cells that have traditionally been thought to generate almost all our energy in the form of ATP. Recent data show that mitochondria are involved in multiple functions including cell signaling and differentiation, fertilization, aging, and apoptosis. Animal mitochondria have their own genome, which is typically described as small (~16 kb), circular and maternally inherited with 37 genes, i.e. 13 for protein-coding genes involved in ATP production, and 22 for transfer RNAs and two for ribosomal RNAs. However, recent data show that the functional repertoire of the animal mtDNA has been underestimated, even in humans. Moreover, while several groups of organisms are relatively conservative in terms of their mt genome content and organization, recent studies revealed that some groups exhibit an astonishing diversity in mt chromosome form and number as well as coding content and organization.

One aim of this Research Topic is to better understand the evolutionary processes that underlie mt genome diversity in animals (and also other organisms). Furthermore, some characters, such as atypical secondary structures of transfer RNAs, which have been consistently found in nematodes, insects, spiders, mites and ticks, have potential value to decipher the phylogeny and evolution of animals at a higher level (class, order or family).

This Research Topic also aims to disentangle the phylogeny and evolution of such animal groups at a wide scale, using characters of mt genomes. Overall, this Research Topic will help in elucidating the genetic, life history, and ecological factors that contribute to the evolutionary dynamics of mt genomes in animals.