Hormonal control of protein sequestration in the fat body of Calpodes ethlius Stoll

Abstract

The hemolymph of larvae and pupae of Calpodes ethlius contains proteins which have been characterized by immunodiffusion as belonging to three antigen groups. Extracts of fat body from non-pupating larvae contain antigens 1 and 2. The third antigen was detected in the fat body during the last 24 h of the larval stage. This timing coincides with the initiation of pupal development, and the formation of granules of stored protein in the fat body. Ligation to remove the influence of the prothoracic glands prevents molting, the formation of storage granules, and the appearance of antigen 3 in the fat body. Ligation has no effect on either the presence of antigens 1 and 2 in the fat body, or of all three antigens in the blood. It is concluded that the uptake of antigen 3 by fat body cells requires the presence of ecdysone.