title: Organization of the sex-ratio meiotic drive region in Drosophila simulans.
abstract: Sex-ratio meiotic drive is the preferential transmission of the X chromosome by XY males, which occurs in several Drosophila species and results in female-biased progeny. Although the trait has long been known to exist, its molecular basis remains completely unknown. Here we report a fine-mapping experiment designed to characterize the major drive locus on a sex-ratio X chromosome of Drosophila simulans originating from the Seychelles (XSR6). This primary locus was found to contain two interacting elements at least, both of which are required for drive expression. One of them was genetically tracked to a tandem duplication containing six annotated genes (Trf2, CG32712, CG12125, CG1440, CG12123, org-1), and the other to a candidate region located approximately 110 kb away and spanning seven annotated genes. RT-PCR showed that all but two of these genes were expressed in the testis of both sex-ratio and standard males. In situ hybridization to polytene chromosomes revealed a complete association of the duplication with the sex-ratio trait in random samples of X chromosomes from Madagascar and Reunion.
authors.affiliation: Laboratoire Populations Génétique et Evolution, CNRS UPR 9034, 91198 Gif-sur-Yvette, France. catherine.montchamp@pge.cnrs-gif.fr
authors.forename: Catherine
authors.initials: C
authors.lastname: Montchamp-Moreau
authors.forename: David
authors.initials: D
authors.lastname: Ogereau
authors.forename: Nicole
authors.initials: N
authors.lastname: Chaminade
authors.forename: Alexandre
authors.initials: A
authors.lastname: Colard
authors.forename: Sylvie
authors.initials: S
authors.lastname: Aulard
mesh_terms: D000818:Animals; D001483:Base Sequence; D002875:Chromosomes; D004330:Drosophila / Q000166:cytology / Q000235:genetics*; D005260:Female; D005456:Fluorescent Dyes; D020440:Gene Duplication; D017344:Genes, Insect; D005819:Genetic Markers; D017403:In Situ Hybridization; D007211:Indoles; D008297:Male; D008540:Meiosis; D008969:Molecular Sequence Data; D020161:Physical Chromosome Mapping; D011995:Recombination, Genetic; D012744:Sex Ratio; D014960:X Chromosome
chemical_list: D005456:Fluorescent Dyes; D005819:Genetic Markers; D007211:Indoles; C007293:DAPI