Transgenic mice will be made using a site-specific yeast recombinase, FLP, under direction of either the insulin or the hox promoter to permanently activate expression of beta-galactosidase in specific cells. Those cells, as well as their progeny, that transiently express insulin or hox during development of the nervous system will be marked. This method also has the potential for introducing an FLP site into cells so that DNA an be integrated into predetermined chromosomal locations in specific cell types. Through the use of various promoters, this method has enormous potential for mapping gene expression patterns during development and for studying effects of gene deletion and gene function. Transgenic mice developed with this technology will be particularly valuable to studies of development of specificity and function in the nervous system.
