Development of an anti-vitellin ELISA for the assessment of reproduction in the ridgeback shrimp, Sicyonia ingentis

To investigate the reproductive regulation of the ridgeback shrimp, Sicyoni a ingentis, vitellin (Vn) synthesis was studied. Using gel filtration chrom atography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, Vn was found to have a molecular mass of 322 kDa and to be composed of three subunits of 182, 91 and 85 kDa. Purified Vn was used to prepare anti-Vn ant iserum, which was used to develop an enzyme-linked immunosorbent assay (ELI SA) with a dynamic range of 0.3-300 ng. The ELISA was used to measure hemol ymph levels of yolk proteins. The mean hemolymph concentrations in fresh ca ught animals ranged from 256 (+/- 36.6 S.E.M.) to 1073 (+/- 87.6 S.E.M.) mg /ml in stage 2 and 4 animals, respectively. The ELISA was also used to dete rmine the effects of steroid hormone injections in adult non-reproductive f emale shrimp. One milligram injections of progesterone, 17 alpha -hydroxypr ogesterone or 17 beta -estradiol were administered for three consecutive da ys to individual females. There were no changes in hemolymph vitellogenin l evels during the successive 7-day period following the first injection of a ny steroid. (C) 2000 Elsevier Science Inc. All rights reserved.