Repression of hybrid dysgenesis in Drosophila melanogaster by combinations of telomeric P-element reporters and naturally occurring P elements.
In Drosophila melanogaster, hybrid dysgenesis occurs in the germline of flies produced by crosses between females lacking P elements and males carrying 25-55 P elements. We have previously shown that a complete maternally inherited repression of P transposition in the germline (P cytotype) can be elicited by only two autonomous P elements located at the X chromosome telomere (cytological site 1A). We have tested whether P transgenes at 1A, unable to code for a P-repressor, may contribute to the repression of P elements. Females carrying a P-lacZ transgene at 1A ["P-lacZ(1A)"], crossed with P males, do not repress dysgenic sterility in their progeny. However, these P-lacZ(1A) insertions, maternally or paternally inherited, contribute to P-element repression when they are combined with other regulatory P elements. This combination effect is not seen when the P-lacZ transgene is located in pericentromeric heterochromatin or in euchromatin; however a P-w,ry transgene located at the 3R chromosome telomere exhibits the combination effect. The combination effect with the P-lacZ(1A) transgene is impaired by a mutant Su(var)205 allele known to impair the repression ability of the autonomous P elements at 1A. We hypothesized that the combination effect is due to modification of the chromatin structure or nuclear location of genomic P elements.
Ronsseray
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Département Dynamique du Génome et Evolution, Institut Jacques Monod, Unité Mixte de Recherche 7592, Centre Nationale de la Recherche Scientifique-Universités Paris 6 et 7, 75251 Paris cedex 05, France.ronsseray@ijm.jussieu.fr
Marin
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L
Lehmann
M
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Anxolabéhère
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D
D000818:Animals; D002467:Cell Nucleus / Q000235:genetics; D002843:Chromatin / Q000235:genetics; D000090266:Chromobox Protein Homolog 5; D003433:Crosses, Genetic; D004251:DNA Transposable Elements; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000235:genetics*; D005260:Female; D017344:Genes, Insect; D005809:Genes, Regulator; D017930:Genes, Reporter; D008040:Genetic Linkage; D006824:Hybridization, Genetic; D007247:Infertility, Female / Q000235:genetics; D008297:Male; D009154:Mutation; D016615:Telomere / Q000235:genetics; D014960:X Chromosome / Q000235:genetics
D002843:Chromatin; D004251:DNA Transposable Elements; D029721:Drosophila Proteins; C000716867:Su(var)205 protein, Drosophila; D000090266:Chromobox Protein Homolog 5