title: Phylogenetics in Caenorhabditis elegans: an analysis of divergence and outcrossing.
abstract: This study establishes a phylogenetic framework for the natural geographic isolates of the widely studied nematode species Caenorhabditis elegans. Virtually complete mitochondrial genomes are sequenced from 27 C. elegans natural isolates to characterize mitochondrial divergence patterns and to investigate the evolutionary history of the C. elegans hermaphrodite lineages. Phylogenetic analysis of mitochondrial sequences reveals the presence of two major C. elegans hermaphrodite clades (designated clade I and clade II). Fifty-six nuclear loci, widely distributed across the five autosomes and the X chromosome, are also analyzed in a subset of the C. elegans isolates to evaluate nuclear divergence patterns and the extent of mating between different strains. A comparison of the phylogenetic tree derived from mitochondrial data with the phylogenetic tree derived from nuclear data reveals only one inconsistency in the distribution of isolates into clades I and II, suggesting that mating between divergent C. elegans strains is an infrequent event in the wild.
authors.affiliation: Division of Molecular Biology and Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, Kansas City, Missouri, USA. ddenver@bio.indiana.edu
authors.forename: Dee R
authors.initials: DR
authors.lastname: Denver
authors.forename: Krystalynne
authors.initials: K
authors.lastname: Morris
authors.forename: W Kelley
authors.initials: WK
authors.lastname: Thomas
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000145:classification* / Q000235:genetics*; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D004272:DNA, Mitochondrial / Q000235:genetics*; D014644:Genetic Variation; D005843:Geography; D010802:Phylogeny
chemical_list: D004272:DNA, Mitochondrial