Abstract
The administration of ecdysterone to mice is accompanied by the incorporation of orotic acid into ribonucleic acids in the liver. This effect was completely repressed by actinomycin D. Judging from the template activity of RNA in an amino acid-incorporating system and the results of sucrose gradient analysis, it is obvious that the rate of synthesis of messenger RNA is regulated by ecdysterone as well as other RNA in mouse liver. The stimulating effect of ecdysterone on protein synthesis reported previously can be explained at least partially in terms of its influence on messenger RNA synthesis.
