Submitted to: Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 29, 1996
Publication Date: N/A
Interpretive Summary: The ability to achieve gene transfer in economically important insects would facilitate biological control of insect pests, depends upon an understanding of mobile DNA (transposon) function in host insects. One gene transfer vector, hobo, is effective in mediating germline transformation in drosophila flies. Scientists at the Insect Attractants Laboratory in Gainesville, Florida describe results from experiments designed to test the function (mobility) of the hobo gene- transfer vector in economically important tephritid fruit fly species. In addition, we present evidence for the identification of DNA sequences, which are related to hobo in these species. Unlike previous transposon vectors tested, hobo function occurred in embryos of all the fruit fly species tested. This indicates that hobo is not functionally restricted and may be useful as a gene vector for germline transformation in these species. Furthermore, in four of five tephritid species, hobo-related elements were identified and isolated. Future research will be focused on the development of these hobo-related elements into gene vectors, as a basis for improvements in the sterile male technique of control.
Technical Abstract: The ability of hobo transposon-based vectors to function in tephritid species was tested by assaying the excision of plasmid-borne hobo elements in embryonic transient assays. Wild type and mutant strains of anastrepha suspensa, bactrocera dorsalis, bactrocera cucurbitae, ceratitis capitata, and toxotrypana curvicauda were all able to support hobo transposase. Although the excisions required the presence of hobo sequences, the mobilizing systems appear to be mechanistically different from, and may interact negatively with, hobo. To determine if the cross-mobilization could be due to hobo-related elements, genomic DNA from each species was amplified by polymerase chain reaction using primers to consensus amino acid sequence in hobo and Activator. For all species except T. curvicauda, PCR products were generated of similar size to hobo, which encode open-reading frames (the C. capitata sequence has a single stop codon. Hybridization studies showed that the sequences all exist as multiple genomic elements in the tephritid strains tested for excision activity, and that the B. cucurbitae element also exists in B. dorsalis. The sequences had varying levels of nucleotide and amino acid sequence homology to hobo. This indicates that hobo-related elements, members of the hAT superfamily, exist in these tephritid species.