Fig. 1. Cranioabdominoschisis and ectodermal dysplasia in bi-transgenics. (a) Overall morphology of wild-type and K5tTA/TRE-KLF5 bi-transgenic embryos at E16.5. (b) Skeletons of E17.5 embryos. The skeletons were double-stained with Alizarin Red and Alcian Blue. Bone is stained red and cartilage is blue. (c) Skull sections of E16.5 embryos. Bars, 500 µm. (1) Haematoxylin-Eosin-stained skull sections showing absence of vibrissae follicles and incisors in the bi-transgenic embryo. (2) Immunohistochemical staining with anti-keratin5 antibody showing the arrested molar development at the early bud-stage in the bi-transgenic embryo. (3) Immunohistochemical staining with anti-keratin5 antibody showing the absence of eyelid formation in the bi-transgenic embryo. (d) Expression of the KLF5 transgene in E16.5 embryos analysed by (1) RT-PCR and (2) immunohistochemistry using anti-Klf5 antibody. Bar, 50 µm.