|Gomez, Sheilachu - UNIV OF FL GAINESVILLE FL|
Submitted to: Genetical Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 10, 1997
Publication Date: July 3, 1997
Citation: Handler, A.M., Gomez, S.P. 1997. P-element excision in Drosophila is stimulated by gamma-irradiation in transient embryonic assays. Genetical Research. 70:75-78. Interpretive Summary: The ability to achieve efficient gene transfer in economically important insects, which is a major goal of our laboratory at the CMAVE, depends upon an understanding of gene transfer vector function and regulation in host insects. The P element transposon functions as a vector in Drosophila, but not in other insects. In an effort to stimulate P vector function, we have tested the ability of gamma-irradiation to promote mobility of the P element transposon. We report in this study a positive dose response between gamma-irradiation and P mobility in insect embryo assays in Drosophila, which is only limited by the negative organismal effects of the radiation. This suggests that gamma-irradiation treatment may be used to stimulate P gene-transfer vector function, and possibly other vector systems as well, in tephritid fruit flies. Continued studies will test the ability of P to be mobilized by irradiation in the Caribbean fruit fly.
Technical Abstract: The influence of gamma-irradiation on P-element excision was directly tested in embryonic somatic excision assays. Preblastoderm embryos having a stable source of somatically active P transposase were irradiated previous to injection with P excision indicator plasmids. Frequencies of precise or nearly precise P excision increased with gamma-ray doses ranging from 50 to 300 rads. Higher doses resulted in smaller increases above baseline frequencies, though considerable embryonic lethality was also evident at these doses. A direct positive interaction between gamma- irradiation and P-element activity is concluded.