TRANSPOSITION OF THE MARINER ELEMENT FROM DROSOPHILA-MAURITIANA IN ZEBRAFISH

With the increased popularity of zebrafish (Danio rerio) for mutagenes is studies, efficient methods for manipulation of its genome are neede d. One approach is the use of a transposable element as a vector for g ene transfer in this species. We report here the transformation of zeb rafish and germ-line transmission of the mariner element from Drosophi la mauritiana. The mariner element was selected because its transposit ion is independent of host-specific factors. One- to two-cell-stage ze brafish embryos were coinjected with a supercoiled plasmid carrying th e nonautonomous mariner element peach and mRNA encoding the transposas e, Surviving larvae were reared to adulthood, and the transmission of peach to the F-1 generation was tested by PCR. Four of the 12 founders , following plasmid injections on 2 different days, transmitted the el ement to their progeny. Inheritance of the transgene from the F-1 to t he F-2 generation showed a Mendelian pattern. No plasmid sequences mer e detected by PCR or Southern blot analysis, indicating transposition of peach rather than random integration of the plasmid DNA. These data provide evidence of transformation of a vertebrate with a transposabl e element and support the host-independent mechanism for transposition of the mariner element. We suggest this system could be used for inse rtional mutagenesis or for identifying active regions of the genome in the zebrafish.