PURIFICATION, DEVELOPMENTAL PROFILE AND BIOSYNTHESIS OF ARYLPHORIN INTHE WILD SILKMOTH, ANTHERAEA-PERNYI

We purified Antheraea pernyi arylphorin (ApA) from the larval hemolymp h by gel permeation chromatography, DE-52 cellulose column chromatogra phy, and hydroxyapatite column chromatography. Our results show that A pA is a hexameric protein with a native molecular weight of 450,000, a nd-consists of three molecules of two subunits each weighing 83,000 an d 82,000. ApA is rich in tyrosine (8.2%) and phenylalanine (8.4%) and poor in methionine (1.4%). The amounts of ApA in the hemolymph increas ed during the feeding stage and decreased during the molting stage. Ap A was partially recaptured by the fat bodies during the larval-pupal m etamorphosis. ApA remained in the hemolymph and also in the fat bodies at a constant level throughout the diapause pupal stage but was then reduced to traces just before adult emergence. In vitro translation of RNA from the fat bodies and immunoprecipitation using anti-ApA serum showed that ApA synthesis occurs in the fat bodies through the feeding stage but is reduced remarkably after spinning. The translatable ApAm RNA was not detected at pupation at all.