Protein and RNA synthesis in the premolt crayfish, Orconectes virilis

Abstract

1. The protein and RNA content of the hepatopancreas of the crayfish Orconectes virilis increases during the normal premolt stage while the quantity of DNA remains unchanged. Eyestalk removal from intermolt animals elicits premolt activity including changes in RNA and protein content similar to that observed in normal premolt crayfish. 2. The rate of incorporation of labelled leucine into hepatopancreatic protein in vitro increased during early premolt and decreased at late premolt. The rate of incorporation of 3H-uridine into hepatopancreatic RNA in vitro was essentially constant from intermolt to mid-premolt but increased at late premolt. 3. No striking changes occurred in the rates of protein synthesis or RNA synthesis when the hepatopancreas was incubated in vitro in the presence of crustecdysone or eyestalk extracts (molt inhibiting hormone).