title: Long-term patterns of genomic P element content and P-M characteristics of Drosophila melanogaster in eastern Australia.
abstract: A latitudinal cline in characteristics associated with the P DNA transposable element is well known in eastern Australian populations of Drosophila melanogaster. In order to survey the long-term patterns of P-M system characteristics and genomic P element content, we established 292 isofemale lines from 54 localities in 1996-1997 and evaluated them for gonadal dysgenesis (GD) sterility and the ratio of KP to full-size P elements (KP/FP ratio). The results were compared to those from collections made in 1983-1986 and 1991-1994. Over 10-14 years, 1) the cross A GD scores of the northern-middle populations declined dramatically; 2) the clinal pattern of the cross A* GD scores did not change; 3) the latitudinal pattern of the KP/FP ratio did not change. The results suggest that only a few P elements determine P-M characteristics and that there has been selection for genomes with fewer active P elements, but not for a great change in proportions of size classes.
authors.affiliation: Department of Biology, Loyola University of Chicago, IL 60626, USA.
authors.forename: Keiji
authors.initials: K
authors.lastname: Ogura
authors.forename: R C
authors.initials: RC
authors.lastname: Woodruff
authors.forename: Masanobu
authors.initials: M
authors.lastname: Itoh
authors.forename: Ian A
authors.initials: IA
authors.lastname: Boussy
mesh_terms: D000818:Animals; D001315:Australia; D004251:DNA Transposable Elements; D003710:Demography; D004331:Drosophila melanogaster / Q000235:genetics*; D005787:Gene Frequency; D017344:Genes, Insect; D005828:Genetics, Population; D049750:Genome, Insect; D006239:Haplotypes; D010641:Phenotype
chemical_list: D004251:DNA Transposable Elements