A translocated mitochondrial cytochrome b pseudogene in voles (rodentia: Microtis)

J. Andrew DeWoody, 1 Ronald K. Chesser, 2 Robert J. Baker 1

1 Department of Biological sciences, Texas Tech University

2 Savannah River Ecology Lab and Department of Genetics, University of Georgia, Athens, GA 30602, USA

Abstract. A full-length cythohrome b pseudogene was found in rodents; it has apparently been dislocated from mitochondrion to the nuclear genome in the subfamily Arvicolinae. The pseudogene (ψcytb) differed from its mitochondrial counterpart at 201 of 1143 sites (17.6%) and by four indels. Cumulative evidence suggests that the pseudogene has been translocated to the nucleus. Phylogenetic reconstruction indicates that the pseudogene arose before the diversification of M. arvalis/M. rossiaemeridionalis from M. oeconomus, but after the divergence of the peromyscine/sigmodontine/arvicoline clades some ~10 MYA. Published rates of divergence between mitochondrial genes and their nuclear pseudogenes suggest that the translocation of this mitochondrial gene to nuclear genome occurred some 6 MYA, in agreement with the phylogenetic evidence.