Rate of protein synthesis: regulation during first division cycle of sea urchin eggs.

Protein synthesis in fertilized sea urchin eggs, or in 12,000g supernatants derived from them, increased linearly during the period preceding prophase of the first mitotic cycle, dropped during metaphase and anaphase, and increased again after telophase. Similar results were observed for whole cells incubated in the presence of colchicine. These changes in the rate of protein synthesis during the mitotic cycle may be regulated at the translational level.