Vitellin and vitellogenin in the soldier bug, Podisus maculiventris: Identification with monoclonal antibodies and reproductive response to diet

A 171,000 M-r polypeptide of Podisus maculiventris (Say) (Heteroptera: Pent atomidae) that constituted 16% of the protein in eggs also constituted up t o 25% of the protein in hemolymph of fed females. It was identified as the major or sole apoprotein of vitellogenin. Eggs contained major polypeptides of 171, 106, and 51 kDa. The hemolymph polypeptide was identified with a p olypeptide (vitellin) in egg extracts by comparing molecular weights, speci ficity of occurrence in fed females, and immunological reactivities. Female s, starved for 5 days after eclosion to assure complete previtellogenic dev elopment, produced vitellogenin within a day after feeding on larval Galler ia mellonella, and within 4 days after feeding on an artificial diet. Appea rance of vitellogenin preceded ovarian growth by 2-3 days. Two monoclonal a ntibodies raised against egg proteins of P. maculiventris were selected for their strong reaction against egg extract and female hemolymph and null re action against male hemolymph. Only one 170-kDa band in egg and hemolymph r eacted with the antibodies on denaturing Western blots. These monoclonal an tibodies are being used to develop an enzyme-linked immunosorbent assay (EL ISA) to quantitate reproductive response of females to diets of differing q uality. Arch. Insect Biochem. Physiol. 44:130-135, 2000. Published 2000 Wil ey-Liss, Inc.dagger