Vitellogenin in the camel cricket Ceuthophilus sp. (orthoptera, gryllacrididae)

Abstract

AbstractHemolymph and egg yolk proteins in the camel cricket, Ceuthophilus sp., were analyzed by native and SDS‐polyacrylamide gel electrophoresis. Four sex‐specific polypeptides (FSYPs I–IV) accounted for 44% of the hemolymph protein in adult females. These polypeptides were absent from the blood of adult males and female nymphs but composed 63% of the yolk protein in fully grown oocytes. Hemolymph FSYPs became labeled with [35S]‐methionine after a 1‐hour period of in vivo incorporation and appeared in terminal, vitellogenic follicles after 2 hours of incorporation. Two‐dimensional gel electrophoresis showed that all four FSYPs occur in a single egg‐yolk glycoprotein also present in adult female hemolymph. We conclude that this glycoprotein is a multisubunit vitellogenin (VG). Two high molecular weight polypeptides synthesized by the fat body of adult females and immunoreactive with VG‐specific antiserum were tentatively identified as proVGs.