title: Instability in the ctMR2 strain of Drosophila melanogaster: role of P element functions and structure of revertants.
abstract: Simultaneous multiple transpositions and long-term genetic instability have been described in the ctMR2 strain of Drosophila melanogaster and its derivatives. This strain originated from a cross that was dysgenic in the P-M system. While spontaneous instability declined over 2 years, instability has been reactivated by backcross to the progenitor P element bearing strain MRh12/Cy. We show here using germline transformation that active P factor alone cannot mimic the effect of this cross, suggesting that MRh12/Cy contains some other activator. In addition, we have observed that ct+ exceptional progeny arise in the F1 as well as the F2 generations. Molecular analysis of X chromosomes from some ct+ progeny indicates that phenotypic reversion of the ct mutation can arise through two unrelated mechanisms.
authors.affiliation: Department of Genetics, University of Edinburgh, Scotland.
authors.forename: A J
authors.initials: AJ
authors.lastname: Brown
authors.forename: S J
authors.initials: SJ
authors.lastname: Ross
authors.forename: L S
authors.initials: LS
authors.lastname: Alphey
authors.forename: A J
authors.initials: AJ
authors.lastname: Flavell
authors.forename: T I
authors.initials: TI
authors.lastname: Gerasimova
mesh_terms: D000483:Alleles; D000818:Animals; D003001:Cloning, Molecular; D004251:DNA Transposable Elements; D004331:Drosophila melanogaster / Q000235:genetics*; D005260:Female; D008297:Male; D009154:Mutation; D009713:Nucleotidyltransferases / Q000235:genetics; D010641:Phenotype; D011110:Polymorphism, Genetic; D015183:Restriction Mapping; D019895:Transposases; D014960:X Chromosome
chemical_list: D004251:DNA Transposable Elements; D009713:Nucleotidyltransferases; D019895:Transposases