title: Segregation distortion in Drosophila melanogaster: genomic organization of Responder sequences.
abstract: The heterochromatic Responder (Rsp) locus of Drosophila melanogaster is the target of the two distorter loci Sd and E(SD). Rsp is located in a specific heterochromatic region of the second chromosome and is made up of AT-rich satellite sequences whose abundance is related to its sensitivity to the distorter chromosomes. Here we report that a cluster of Rsp sequences is also located in the third chromosome. The third-chromosome cluster has the same flanking sequences as the clone originally used to identify the Rsp elements, and one of the flanking sequences is a rearranged 412 retrotransposon. The presence of a second, unlinked Rsp-sequence cluster makes re-interpretation necessary for some earlier experiments in which segregation of the third chromosome had not been followed and raises interesting possibilities for the origin of the Rsp locus.
authors.affiliation: Istituto di Genetica, Università di Bari, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Moschetti
authors.forename: R
authors.initials: R
authors.lastname: Caizzi
authors.forename: S
authors.initials: S
authors.lastname: Pimpinelli
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D004331:Drosophila melanogaster / Q000235:genetics*; D017344:Genes, Insect / Q000235:genetics; D016678:Genome; D005810:Multigene Family