Inhibition of Rock activity rescues delamination of G1-arrested neural crest (NC) cells. (A,D,G,J) Phase contrast. (B,C,E,F,H,I,K,L) Bromo-deoxyuridine (BrdU) immunostaining. (C,F,I,L) Higher magnifications to appreciate the front of the delaminated NC cells. Inhibition of Rock with Y27632 enhanced delamination of BrdU+ NC cells ((D-F) compared to (A-C)). Mimosine blocked both BrdU incorporation and NC delamination following 9 h (G-I), whereas cotreatment with mimosine (Mim) and Y-27632 rescued emigration of G1-arrested, BrdU-negative NC cells (J-L). Bar: 45 μM (A,B,D,E,G,H,J,K); 24 μM (C,F,I,L).