Fig. 1. Spatiotemporal analysis of cre activity directed by the Nestin cre transgene. (A-F) Coronal sections through whole-mount ß-gal staining of E10.5 (A,B), 11.5 (C,D) and 13.5 (E,F) dpc Nestin cre^+/-;R26R^+/- mice showing cre activity in Nestin cre transgenic mice. Cre activity is denoted by the blue color (arrows). Boxed areas in A and E are shown at higher magnification in B and F, respectively. In E and F, ß-gal-positive cells are found throughout the palatal shelves. (G) PCR analysis of dissected tissues from Nestin cre;Bmpr1a n/f embryos at 10.5 dpc. Primers flanking the second LoxP site were used to determine the extent of recombination at the Bmpr1a locus. The upper band is the product of Bmpr1a^flox allele (arrowhead). The lower band is the product of Bmpr1a^null allele and serves as an internal control. M, DNA marker; Md, mandibular process; Mp, maxillary process; Ln, laternal nasal process; Mn, medial nasal process; ps. palatal shelf.