Fig. 2. Expression profile of the –31/+7 Krox20/lacZ transgenic line. (A,B) Transgenic embryos stained for ß-galactosidase activity at 10.5 and 15.5 dpc, respectively. (C) Transverse section through the lumbar region of the embryo shown in B (dorsal to the right). The scale bar represents 200 µm. (D) Hindlimb view of a 18.5 dpc transgenic embryo stained for ß-galactosidase. (E,F) Transverse cryosection and teased preparation of the distal sciatic nerve of transgenic mice at P3 and P30, respectively, stained for ß-galactosidase. The scale bars represent 25 µm. The preparations shown in C, E and F were counterstained with Nuclear Fast Red. V, trigeminal nerve; VII/VIII, facial/acoustic nerve; XI, accessory nerve; VNR, ventral nerve root; DNR, dorsal nerve root; ScN, sciatic nerve; CN, cutaneous nerve.