Fig. 4

Interactions between eve1 and BMP. Lateral views (where discernible, dorsal to the right) of zebrafish embryos at 70–80% epiboly (A–S). Embryos were injected at the one-cell stage (A–K, M, and Q) or at the one– to four-cell stage (N and R). For coinjection of eve1 mRNA and bmp2bMO, embryos first were injected with eve1 at the one-cell stage and then were injected with bmp2bMO at the four- to eight-cell stage (O and S). Genes analyzed are indicated at the left of the rows; injections are indicated at the top of columns. Bmp2b suppresses neural markers sox3 and hoxb1b even in the presence of eve1 (A–F). Bmp4 expression is suppressed by eve1 (H) but is ubiquitously induced by coinjection of bmp2b mRNA (I, compare to G). Bmp2b expression also is suppressed by eve1 (J, K). Eve1 and bmp2bMO synergize in ectodermal fate specification (L–S). Low levels of eve1 mRNA (10 pg/nL) or bmp2bMO (100 pg/nL) injected individually do not affect sox3 or foxi.1 expression (M, N, Q, and R), but coinjection at the same concentrations induced sox3 (O) and suppressed foxi.1 (S).