title: The potential role of sexual conflict and sexual selection in shaping the genomic distribution of Mito-nuclear genes.
abstract: Mitochondrial interactions with the nuclear genome represent one of life's most important co-evolved mutualisms. In many organisms, mitochondria are maternally inherited, and in these cases, co-transmission between the mitochondrial and nuclear genes differs across different parts of the nuclear genome, with genes on the X chromosome having two-third probability of co-transmission, compared with one-half for genes on autosomes. These asymmetrical inheritance patterns of mitochondria and different parts of the nuclear genome have the potential to put certain gene combinations in inter-genomic co-adaptation or conflict. Previous work in mammals found strong evidence that the X chromosome has a dearth of genes that interact with the mitochondria (mito-nuclear genes), suggesting that inter-genomic conflict might drive genes off the X onto the autosomes for their male-beneficial effects. Here, we developed this idea to test coadaptation and conflict between mito-nuclear gene combinations across phylogenetically independent sex chromosomes on a far broader scale. We found that, in addition to therian mammals, only Caenorhabditis elegans showed an under-representation of mito-nuclear genes on the sex chromosomes. The remaining species studied showed no overall bias in their distribution of mito-nuclear genes. We discuss possible factors other than inter-genomic conflict that might drive the genomic distribution of mito-nuclear genes.
authors.affiliation: Department of Genetics, Evolution, and Environment, University College London, London, United Kingdom.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Dean
authors.forename: Fabian
authors.initials: F
authors.lastname: Zimmer
authors.forename: Judith E
authors.initials: JE
authors.lastname: Mank
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics; D002467:Cell Nucleus / Q000235:genetics; D004331:Drosophila melanogaster / Q000235:genetics; D005260:Female; D050259:Genes, Mitochondrial; D016678:Genome; D054629:Genome, Mitochondrial; D040582:Inheritance Patterns; D008297:Male; D008322:Mammals / Q000235:genetics; D010802:Phylogeny; D012641:Selection, Genetic; D012730:Sex Chromosomes; D014960:X Chromosome
keywords: Haldane’s sieve; OXPHOS; X chromosome; Z chromosome; sexual conflict