Regulation of protein synthesis at the translational level in neuroblastoma cells. Protein synthesis in reuroblastoma cells has been studied in a cell-free system. The activity of lysates from cells grown insuspension and monolayer has been compared. A higher level of activity has been found in monolayer cells. The activity of some components of the lysate that are involved in protein synthesis has been analyzed. The data suggest that the controlling step of protein synthesis in this system might be in the initiation process. The correlation between activation of protein synthesis and neurite outgrowth in monolayer cultures is discussed.