Generation of Cre-dependent mosaic transgenic mice.

<p>(A) Transgenic mice based on Cre/Lox recombination were generated by crossing a Cre-transgenic line under a CaMKIIα promoter with a Thy1 promoter-driven EGFP-F transgenic line containing a transcriptional STOP cassette. Bright field microscopy images showing mosaic expression of the β-galactosidase expressing cells in layers II/III and V/VI of the neocortex of R26R mice when crossed with different CaMKIIα promoter-driven Cre-transgenic lines – (B) Cre 3487 and (C) Cre 3510. Epi-fluorescence microscopy images of Cre-dependent EGFP-F expression in TLG 498⁺ Cre 3487⁺ transgenic mice. EGFP-F expression starts at 6 weeks and increases with age. The number of EGFP-F⁺ cells increases from (D) 2 months to (E) 4 months of age. Scale bars: B, D-100 µm; C-200 µm.