title: Molecular characterization of lengthy mitochondrial DNA duplications from the parasitic nematode Romanomermis culicivorax.
abstract: Complete nucleotide sequences, precise endpoints and coding potential of several 3.0-kilobase mitochondrial DNA (mtDNA) repeating units derived from two isofemale lineages of the mermithid nematode Romanomermis culicivorax have been determined. Endpoint analysis has allowed us to infer deletion and inversion events that most likely generated the present day repeat configuration. Each amplified unit contains the genes for NADH dehydrogenase subunits 3 and 6 (ND3 and ND6), an open reading frame (ORF 1) that represents a cytochrome P450-like gene, and three additional unidentified open reading frames. The primary nucleotide sequences of the R. culicivorax mt-repeat copies within individual haplotypes are highly conserved; three nearly complete copies of the repeat unit vary by 0.01% at the nucleotide level. These observations suggest that concerted evolution mechanisms may be active, resulting in sequence homogenation of these lengthy duplications.
authors: Department of Biology, University of California, Riverside 92521.
authors: J L
authors: JL
authors: Azevedo
authors: B C
authors: BC
authors: Hyman
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics*; D005260:Female; D008632:Mermithoidea / Q000235:genetics*; D008969:Molecular Sequence Data; D009245:NADH Dehydrogenase / Q000235:genetics; D016366:Open Reading Frames; D012091:Repetitive Sequences, Nucleic Acid; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
chemical_list: D004272:DNA, Mitochondrial; D003577:Cytochrome P-450 Enzyme System; D009245:NADH Dehydrogenase