FIG. 1.

Time course of inhibition of protein synthesis by emetine in unfertilized eggs (A), 2- to 16-cell embryos (B) and early mesenchyme blastula embryos (C). Unfertilized eggs and embryos were incubated and analyzed for [³H]leucine incorporation into peptides as described under Materials and Methods. At the beginning of the experiment the culture age of B was 0.7 hr and that of C 24 hr. Emetine was added at 1.0 and 0.5 hr after the addition of [³H]leucine, for eggs and embryos, respectively. Control cultures (○). Emetine-treated cultures (●). The percent inhibition was calculated by the comparison of slopes b and c with a as discussed under Results. The times at which parallel cultures were examined for polyribosome content are indicated by arrows.