Fig. 3. The -56.6/-53.7 region drives Myf5-nlacZ expression only in the central nervous system. (A) X-gal staining at E11.5 of an embryo, with a -56.6/-53.7 Myf5-nlacZ transgene, showing nlacZ expression in the embryonic brain (prosomeres p1 and p4) and in the neural tube. The embryo in A was sectioned at levels indicated by the white lines, and sections at these levels are shown in B-D. ß-galactosidase-positive cells are detected in the ventral neural tube (B) and in the neuroepithelium at the levels of prosomeres p1 (C) and p4 (D). In these brain sections, telencephalic vesicles are on the right.