Author
Handler, Alfred - Al | |
GOMEZ, SHEILACHU - Former ARS Employee | |
O'BROCHTA, DAVID - University Of Maryland |
Submitted to: Molecular and General Genetics
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/27/1992 Publication Date: N/A Citation: Handler, A.M., Gomez, S.P., O'Brochta, D.A. 1993. Negative regulation of P element excision by the somatic product and terminal sequences of P in drosophila melanogaster. Molecular and General Genetics. 237:145-151. Interpretive Summary: A transient in vivo P element excision assay was used to test the regulatory properties of putative repressor-encoding plasmids in Drosophila melanogaster embryos by scientists at the USDA Agricultural Research Service, Center for Medical Agricultural and Veterinary Entomology, Gainesville, Florida. The somatic expression of an unmodified transposase transcription unit under the control of a heat shock gene promoter (phsn) effectively repressed P excision in a dose-dependent manner at very low concentrations relative to somatically active transposase (encoded by the hs 2–3 gene). Maximum repression required transcription of the complete transposase gene. Dose-dependent repression of P excision was also observed in the presence of a vector plasmid (pCarnegie4) having only the terminal sequences, including transposase binding sites, of the P element. However, repression required considerably higher concentrations of pCarnegie 4 than phs , and elimination of P excision was not observed. Technical Abstract: A transient in vivo P element excision assay was used to test the regulatory properties of putative repressor-encoding plasmids in Drosophila melanogaster embryos. The somatic expression of an unmodified transposase transcription unit under the control of a heat shock gene promoter (phsn) effectively repressed P excision in a dose-dependent manner at very low concentrations relative to somatically active transposase (encoded by the hs 2–3 gene). Maximum repression required transcription of the complete transposase gene. Dose-dependent repression of P excision was also observed in the presence of a vector plasmid (pCarnegie4) having only the terminal sequences, including transposase binding sites, of the P element. However, repression required considerably higher concentrations of pCarnegie 4 than phs , and elimination of P excision was not observed |