Fig. 2
Grhl3 promotes cytoskeletal networks and multinucleation in vivo. a A schematic construct of the CAG-loxP-lacZ-loxP-Grhl3 (CAG-lacZ-Grhl3) transgene. b LacZ expression in the Tg(CAG-lacZ-Grhl3) blastocyst with X-gal staining. c–f Morphological features of wild type (c, e) and Tg(CAG-Grhl3) (d, f) at E4.5 (c, d), and E5.5 (e, f), respectively. Hematoxylin–eosin sagittal sections. g–l Immunohistochemical analyses of whole embryos at E3.5 in wild type (g, i, k) and Tg (CAG-Grhl3) (h, j, l). Phalloidin (magenta; g, h), CLAUDIN4 (magenta; i, j) and TROMA-1 (magenta; k, l), and DAPI (cyan; g–j, blue; k, l) stains. Multinucleate cells are seen in the inner cell mass region (arrows; h, j). m Schematic protocol for the electroporation of vectors, CAG-EGFP with or without CAG-Grhl3, into the embryo proper at E8.5. n, o Expression of CAG-EGFP vector in the surface ectoderm (SE) after 16 h culture in vitro. Anti-EGFP (green) and TROMA-1 (magenta). p–u Immunohistochemistry of electroporated embryos after 24 h culture in vitro. EGFP (green), phalloidin (magenta), and DAPI (blue). Cell size enlargement and F-actin accumulation are seen in the CAG-Grhl3 electroporated SE (s–u). Representative images from more than two independentexperiments. Scale bars represent 10 (p–u), 50 (b, g–l), 100 (c–f), and 200 μm (n)
