Fig. 5.

Rescue of Gnas^E2–/E2– chondrocytes by rat Gsα. Shown is staining for β-galactosidase activity plus H&E staining of a section of the radii from an E17.5 Gnas^E2–/E2–; pCMV-rGsα/wild-type chimeric embryo. Cells derived from host blastocysts were stained blue with 5-bromo-4-chloro-3-indolyl β-d-galactoside (X-Gal). The earliest hypertrophic chondrocytes (detected by their characteristic morphology) derived from host blastocysts and ES cells were marked with blue and white arrowheads, respectively. The lower portions of the panels for clones 21 and 44 show in situ hybridization for type X collagen mRNA in serial sections. (Scale bar, 100 μm.)