FIG. 5.

Muscles of the diaphragm and tongue of Pax3-FKHR heterozygous pups are abnormal around the time of birth but not at E13.5. (A to D) Hematoxylin and eosin staining of similar transverse sections of P1 wild-type (A and B) and Pax3-FKHR knock-in (C and D) diaphragms showing a much reduced musculature of the mutant diaphragm. (E) Sagittal section of a P1 Pax3-FKHR diaphragm showing gaps (asterisk). (F and G) BrdU incorporation and Pax3 and Pax3-FKHR expression in diaphragms of E13.5 wild-type (F) and Pax3-FKHR knock-in (G) pups. Green, nuclear staining with methylene green; purple, staining with anti-BrdU; brown, staining with anti-Pax3. (H to K) Hematoxylin and eosin staining of similar sagittal sections of the tongue of P1 wild-type (H and I) and Pax3-FKHR mutant (J and K) pups. Abbreviations: d, diaphragm; Li, liver; Lu, lung.