COMPARATIVE-ANALYSIS OF STORAGE PROTEINS OF THE FALL WEBWORM (HYPHANTRIA-CUNEA, DRURY)

Two kinds of storage protein (SP-1 and SP-2) were purified from the he molymph of last instar larvae of Hyphantria cunea by ultracentrifugati on, chromatofocusing, and ion-exchange chromatography. SP-1 and SP-2 e ach consist of six subunits and have the molecular mass of 79 KDa and 82.5 KDa, respectively. These showed different patterns oi appearance in fat body and hemolymph, and different SDS-PAGE patterns in nonreduc ing gels. Their stability in citrate phosphate or Tris-HCl buffers dif fers and their immunological characteristics indicates that these are different storage proteins. Comparison with storage proteins of other species with respect to amino acid composition and N-terminal sequence , indicates that SP-1 can be classified as a methionine-rich storage p rotein but SP-2 cannot be regarded as a classical arylphorin. (C) 1997 Elsevier Science Inc.