Generation and Initial Study of Zebrafish Genomic Instability Mutants

Cheng 9319817 Abstract Zebra fish have many advantages as an experimental organism for developmental studies. However, its use is limited unless it can be developed as a genetic system also. It is proposed that this project will demonstrate the feasibility of using zebra fish as experimental genetic organisms. Mutations that increase genomic instability, e.g. by increasing the rate of chromosome loss or mutation, are expected to increase the frequency of loss of heterozygosity. That loss can be used as a phenotypic screen in that a recessive pigment mutation which can be quantitatively assessed by screening the number of nonpigmented cells in an otherwise pigmented retinal epithelium of three-day old unhatched embryos can be used as a tracer. The mutant candidates can be generated as the progeny of mutagenized gol-1+ males and non- mutagenized gol-1(b1) females. The recessive mutant screen proposed involves inspection under a dissecting microscope of the progeny. Clutches of progeny yielding a potential aggregate of more than 100,000 cells will be scored in situ under a dissecting microscope at three days. A simpler dominant screen will be evaluated in parallel primarily with males after standard crosses. When possible, complementation analysis of recessive mutations, outcrosses and quantitation of the effect of mutations will be begun. %%% The feasibility of developing zebra fish as useful genetic organisms will be determined. The strains necessary for the projected screen for mutant progeny will be generated. Genomic instability mutants, both dominant and recessive, will be generated. When possible, the mutants will be characterized and karyotyping will be attempted. ***