Comparative biochemical and immunological analysis of the three vitellogenins from Drosophila grimshawi

1. The three female-specific vitellogenin proteins, namely V1, V2 and V3, have been isolated and characterized from Drosophila grimshawi. Their mol. wt, as determined by SDS-polyacrylamide gel electrophoresis are 46,000, 45,000 and 43,000 which are in agreement with those determined by Ferguson plot analysis. 2. All three vitellogenins appear to be monomers in the ovarian extracts and they have very similar biochemical and immunological properties. 3. Ion-exchange chromatography, double immunodiffusion tests and partial digestion with Staphylococcus aureus V8 protease indicated more physicochemical and structural similarities between the V1 and the V2 polypeptides. 4. The distribution pattern of the proteolytic polypeptides resulting from limited chymotrypsin digestion suggested partial homology in the primary structure of the three vitellogenin proteins.