Figure 1.

Generation of Grin2b-flox and Grik4-Cre mice. A, Schematic representations of GluK4 cDNA, genomic DNA (Grik4^wt), and targeted genome (Grik4^Cre). The gray boxes indicate exons. The black boxes indicate the probes for Southern blot analysis. The filled circles in the Grik4^Cre allele delineate the 5′ and 3′ termini of the targeting vector. The semicircles indicate FRT sequences. Met, Initial methionine; Cre, Cre recombinase gene; neo, neomycin-resistant gene expression cassette; Xb, XbaI; ET, EcoT₂₂-I. B, Southern blot analysis of XbaI- or EcoT₂₂-I-digested genomic DNA prepared from the wild-type (Grik4^+/+) and heterozygous Cre (Grik4^Cre/+) mice. C, β-Galactosidase activity induced by Grik4-Cre in 4-week-old reporter mice. a, β-Galactosidase staining of a whole-brain slice (50 μm thick). b, c, Hippocampus, counterstained with nuclear fast red (NFR) (b) or reacted with anti-calbindin antibody (c). d, e, CA3 region. Parvalbumin (d) and glutamine synthase (e) were stained with respective antibodies as markers for interneurons and glial cells, respectively. Scale bars: a, 3 mm; b, c, 100 μm; d, e, 10 μm. D, Schematic representations of GluN2B cDNA, genomic DNA (Grin2b^wt), targeted genome (Grin2b^flox), and Cre-mediated deleted genome (Grin2b^del). The gray boxes indicate exons. The black boxes indicate the probes for Southern blot analysis. The triangles indicate loxP sequences. The filled circles in the Grin2b^flox allele delineate the 5′ and 3′ termini of the targeting vector. Nh, NheI; Nd, NdeI. E, Southern blot analysis of NdeI- or NheI-digested genomic DNA prepared from the wild-type (Grin2b^+/+), heterozygous floxed (Grin2b^+/flox), homozygous floxed (Grin2b^flox/flox), and heterozygous floxed and deleted (Grin2b^flox/del) mice. F, Immunoblot analysis of whole-brain crude fraction prepared from the wild-type, heterozygous (Grin2b^+/flox), and homozygous floxed (Grin2b^flox/flox) mice at P0.5 with anti-GluN2BC and anti-NSE antibodies.