Preferential transposition of Drosophila P elements to nearby chromosomal sites.
Two different schemes were used to demonstrate that Drosophila P elements preferentially transpose into genomic regions close to their starting sites. A starting element with weak rosy+ marker gene expression was mobilized from its location in the subtelomeric region of the 1,300-kb Dp1187 minichromosome. Among progeny lines with altered rosy+ expression, a much higher than expected frequency contained new insertions on Dp1187. Terminal deficiencies were also recovered frequently. In a second screen, a rosy(+)-marked element causing a lethal mutation of the cactus gene was mobilized in male and female germlines, and viable revertant chromosomes were recovered that still contained a rosy+ gene due to an intrachromosomal transposition. New transpositions recovered using both methods were mapped between 0 and 128 kb from the starting site. Our results suggested that some mechanism elevates the frequency 43-67-fold with which a P element inserts near its starting site. Local transposition is likely to be useful for enhancing the rate of insertional mutation within predetermined regions of the genome.
Tower
J
J
Howard Hughes Medical Institute Research Laboratories, Carnegie Institution of Washington, Baltimore, Maryland 21210.
Karpen
G H
GH
Craig
N
N
Spradling
A C
AC
D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D002875:Chromosomes; D004251:DNA Transposable Elements / Q000235:genetics; D004331:Drosophila melanogaster / Q000235:genetics*; D005260:Female; D005804:Genes, Lethal; D017403:In Situ Hybridization; D008297:Male; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D011995:Recombination, Genetic; D017384:Sequence Deletion
D004251:DNA Transposable Elements