Generation and Characterization of Photoreceptor-specific Cre Transgenic Mice

Abstract

Abstract: : Purpose: Disruption of fundamental genes in mice often leads to embryonic and neonatal lethality. To circumvent this problem and study functions of genes involved in the lipid second messenger pathways, we decided to establish a photoreceptor-specific knockout system using the Cre/lox system. Methods: Transgenic mice carrying a mouse opsin promoter-directed Cre transgene were generated. The Cre transgenic mice were screened with PCR and confirmed with Southern hybridization. Mouse strains expressing Cre were identified with RT-PCR and/or Western blot analysis using mRNAs and proteins made from retina. Candidate Cre-expressing mice were further characterized with the functional studies using a Cre-activatable lacZ reporter mouse strain. Results: Thirty opsin-Cre transgenic mice were generated, and several strains expressed Cre in retina. Beta-galactosidase assay on retinal flat mounts and sections of F1 mice derived from the opsin-Cre transgenic mice and the lacZ reporter mice suggested that at least one of mouse strains was capable of carrying out productive Cre-mediated recombination in photoreceptor cells. Conclusion: We have generated transgenic mice that efficiently express Cre recombinase in photoreceptor cells. These mice can be used in gene function studies in photoreceptor cells.

Keywords: animal model • gene/expression • photoreceptors