Fig 1. The neural crest specific ablation of Fgfr and Frs2 disrupted lacrimal gland development.

(A-N) Lacrimal gland budding occurred in Fgfr1 and Fgfr2 single, but not in double, mutants (A-H, arrowheads). A mutation of the Frs2 binding site on Fgfr1 (Fgfr1^ΔFrs) or Fgfr2 (Fgfr2^L/R), or the deletion of Frs2 altogether resulted in the disruption of lacrimal gland development (I-N, arrowheads). Note that the severity of the craniofacial phenotype does not always correlate with the defects present in the lacrimal gland (compare C, D, M and N). Arrow: craniofacial abnormalities. Arrowheads: lacrimal gland primordia. e: eye. (O-P) Although Pdgfra was expressed in the periocular mesenchyme (O, arrow), its deletion in the neural crest did not affect lacrimal gland budding (P, arrow). (Q) Quantification of lacrimal gland phenotype.