title: Conservation of the global sex determination gene tra-1 in distantly related nematodes.
abstract: Sex determination has long intrigued evolutionists, geneticists, and developmental biologists in a similar way. Substantial evidence indicates that sex determination evolves rapidly and, therefore, can be used to study how molecular patterning processes evolve. In Caenorhabditis elegans, sex determination relies on a signaling pathway that involves a cascade of negatively acting factors, finally triggering the GLI-family zinc-finger transcription factor TRA-1. We have started to investigate sex determination in the nematode satellite species Pristionchus pacificus that is separated from C. elegans for 200-300 million years. In P. pacificus, animals with two X chromosomes develop as hermaphrodites, whereas XO animals develop as males. We used an unbiased forward genetic approach and isolated several mutants with a hermaphrodite to male transformation of the XX karyotype. We identified one complementation group as representing the P. pacificus ortholog of tra-1, providing the first evidence for the conservation of a global sex determination gene over a time period of at least 200 million years. A Ppa-tra-1 morpholino phenocopies Ppa-tra-1 mutants and establishes the morpholino technology as a reverse genetic approach in P. pacificus.
authors.affiliation: Max-Planck Institut für Entwicklungsbiologie, Abteilung Evolutionsbiologie, Spemannstrasse 37-39, D-72076 Tübingen, Germany.
authors.forename: André
authors.initials: A
authors.lastname: Pires-daSilva
authors.forename: Ralf J
authors.initials: RJ
authors.lastname: Sommer
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D005075:Biological Evolution; D017173:Caenorhabditis elegans / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins / Q000235:genetics; D017124:Conserved Sequence; D018509:DNA, Helminth / Q000235:genetics; D005260:Female; D017238:Genes, Helminth; D005816:Genetic Complementation Test; D015801:Helminth Proteins / Q000235:genetics; D008297:Male; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation; D009348:Nematoda / Q000235:genetics*; D010641:Phenotype; D017386:Sequence Homology, Amino Acid; D019849:Sex Determination Processes; D013045:Species Specificity
chemical_list: D029742:Caenorhabditis elegans Proteins; D018509:DNA, Helminth; D015801:Helminth Proteins