Nonlethal detection of transgene expression in the CNS of founder mice

Determining whether transgenes targeted to the central nervous system (CNS) are expressed has previously required sacrificing fire animal; thus, if a line was to be maintained, it was necessary to generate offspring from the original founder mouse before assay We describe a method for assaying far t he expression of a variety of CNS-targeted transgenes that allows for the s urvival of the founder mice. Many CNS genes are expressed in the retina whi ch can be obtained from a mouse by simple survival surgery. We demonstrate that reverse transcription PCR of RNA isolated from a single eye carr detec t the mRNAs for glial fibrillary acidic protein (GFAP), vimentin, neurofila ment light chain (NF-68) and Thy-I, all of whose promoters hale been used t o direct transgene expression in the CNS. We also show that this method, re adily detects expression of an astrocyte-specific GFAP-driven lacZ transgen e and a neuron-specific L7-driven lacZ transgene.