A diapause associated protein of the pink bollworm Pectinophora gossypiella saunders

A diapause associated protein was electrophoretically isolated from the hemolymph of diapausing last instar larvae of the pink bollworm Pectinophora gossypiella . This protein (M r ∼490,000, glycolipoprotein) was given the name Pectinophora diapause protein (PDP). It is composed of one subunit (M r 103,000). The concentration of PDP increased dramatically in the hemolymph of diapausing larvae from 17.4% in prediapause (PD) phase to 29.2% in early diapause (ED) phase reaching a level of 38.6% in larval hemolymph of middiapause (MD) phase. The concentrations of total proteins in the hemolymph of active feeding (A), PD, ED, and MD larvae were 69.8, 106.6, 113.3, and 118 mg/ml, respectively, while those in the fat body of the same larvae were 7.1, 7.4, 8.8, and 4.5 mg/g, respectively. In Pectinophora a drop in the concentration of fat body proteins coincided with a corresponding increase in hemolymph proteins, which suggests an active release of protein from the fat body into the hemolymph during the development of diapause. A partial amino acid sequence of pectinophorin showed the first 15 amino acids starting from the amino terminus of the peptide chain: N‐ALA‐LYS‐THR‐ILEU‐VAL‐GLU‐ASN‐MET‐PRO‐PRO‐THR‐PRO‐LEU‐ASN‐ALA‐C. © 1992 Wiley‐Liss, Inc.