frontonasal region from embryos in G and H respectively. Scale bar in A–D = 200 mm; E,F = 330 mm; G,H = 400 mm. (TIF) Figure S2 Expression of Rock1 in the pharyngeal arch and Rock2 in the developing craniofacial region at E10.5. A–D) Rock1 (red) is expressed throughout the pharyngeal arch at E9.5 (A,B) and E10.5 (C,D). E–G) Rock2 protein is expressed in and around the dorsal root ganglia, adjacent to the neural tube (E), within pharyngeal arch 1 (F), and within the ectomesenchyme of the frontonasal processes (G). fnp = frontona- sal process; nt = neural tube; pa1 = pharyngeal arch 1. Scale bar A–E = 50 mm. (TIF) References 1. Cordero DR, Brugmann S, Chu Y, Bajpai R, Jame M, Helms JA (2011) Cranial neural crest cells on the move: Their roles in craniofacial development. Am J Med Genet A 155A(2): 270–9. 2. Minoux M, Rijli FM (2010) Molecular mechanisms of cranial neural crest cell migration and patterning in craniofacial development. Development 137(16): 2605–21. 3. 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