Vitellogenesis in the stable fly, stomoxys calcitrans

Abstract 1. 1. No female specific proteins were found in the stable fly hemolymph by polyacrylamide gel electrophoresis. 2. 2. Six major yolk polypeptides (YP1, YP2, YP3, YP4, YP5 and YP6) have been identified in the stable fly. Their mol. wt as determined by SDS-polyacrylamide gel electrophoresis are 41,100, 42,600, 44,100, 46,600, 48,900 and 50,600, respectively. 3. 3. YP3 was purified and antibody made against it. By using the antibody and in vitro organ culture the stable fly yolk polypeptides were shown to be synthesized exclusively by the ovaries and not the fat body. 4. 4. The stable fly yolk polypeptides are immunologically similar to yolk proteins of other related flies.