Fig. 3.
Osterix-lacZ (Osx-Z) expression is detectable in MD mesenchyme during regression in males but absent in females. (A–J) Whole-mount β-galactosidase staining of OsxZ/+ female and male reproductive tracts. (A–E) No expression is detected in female embryos from E13.75 to E17.5. (F and G) Osx-lacZ is expressed in male embryos beginning at E13.75 and by E14.5 is expressed in the mesenchyme throughout the length of the MD. (H–J) As the MD regresses, Osx-lacZ expression is also lost. b, bladder; o, ovary; t, testis; (Scale bar: 500 µm.)