The unusual system of doubly uniparental inheritance of mtDNA: isn't one enough?
Mitochondria possess their own genetic material (mitochondrial DNA or mtDNA), whose gene products are involved in mitochondrial respiration and oxidative phosphorylation, transcription, and translation. In animals, mitochondrial DNA is typically transmitted to offspring by the mother alone. The discovery of 'doubly uniparental inheritance' (DUI) of mtDNA in some bivalves has challenged the paradigm of strict maternal inheritance (SMI). In this review, we survey recent advances in our understanding of DUI, which is a peculiar system of cytoplasmic DNA inheritance that involves distinct maternal and paternal routes of mtDNA transmission, a novel extension of a mitochondrial gene (cox2), recombination, and periodic 'role-reversals' of the normally male and female-transmitted mitochondrial genomes. DUI provides a unique opportunity for studying nuclear-cytoplasmic genome interactions and the evolutionary significance of different modes of mitochondrial inheritance.
Breton
Sophie
S
Département de Biologie, Université du Québec à Rimouski, 300 Allée des Ursulines, Rimouski, Québec, G5L 3A1, Canada. sophie_breton@uqar.qc.ca
Beaupré
Hélène Doucet
HD
Stewart
Donald T
DT
Hoeh
Walter R
WR
Blier
Pierre U
PU
D000220:Adaptation, Biological / Q000235:genetics; D000818:Animals; D049872:Bivalvia / Q000235:genetics*; D019143:Evolution, Molecular; D005260:Female; D050259:Genes, Mitochondrial; D016678:Genome; D008297:Male; D008954:Models, Biological; D008957:Models, Genetic; D010802:Phylogeny; D012737:Sex Factors