Direct determination of retrotransposon transposition rates inDrosophila melanogaster

Publisher Website
Google Scholar
Abstract
Summary: Rates of transposition and excision of theDrosophila melanogasterretrotransposon elementsmdg3, 297, Doc, rooandcopiawere estimated directly, byin situhybridization analysis of their cytological insertion sites in 31 replicates of a highly inbred line that had accumulated spontaneous mutations for approximately 160generations. Estimated transposition rates ofDoc, rooandcopiawere, respectively, 4·2 × 10−5, 3·1 × 10−3and 1·3 − 10−3; no transpositions of297normdg3were observed. Rates of transposition ofcopiavaried significantly among sublines. Excisions were only observed forrooelements, at a rate of 9·0 × 10−6per element per generation. Copy number averaged over these element families increased 5·9 %; therefore, in these lines the magnitude of the forces opposing transposable element multiplication were weaker than transposition rates.