A larval specific lipoprotein: Purification and characterization of a blue chromoprotein from Heliothis zea

The green color of the hemolymph of last instar larvae of the corn earworm, Heliothis zea (Boddie), is caused by the appearance of a blue chromoprotein. This protein (M r ∼ 560,000) is composed of 4 subunits (M r ∼ 150,000). It contains 8.4 % lipid and has an equilibrium density of 1.26 g/ml. This protein is absent during all early larval stages, in pupae and in adult animals, but is a major hemolymph protein in 5 th instar larvae. Although its physiological function remains unclear, this blue chromoprotein represents the first member of a new class of larval-specific insect lipoproteins.