KR Mewes, M Latz Zoologisches Institut,Abt.I, Universität Mainz, 55099 Mainz, Germany

In all higher egg-laying vertebrates estradiol-17b (E2) plays a crucial role in the induction and regulation of vitellogenesis. Although vitellogenin is synthesized only in the liver of females during their reproductive period, vitellogenin synthesis can be artificially induced by doses of estradiol-17b in male animals, as, for example, reported for rooster (1), xenopus (2), and sea bass (3). Male river lampreys were injected twice with 100 µg estradiol-17b, and blood samples were collected before and two weeks after the first injection. The plasma samples were investigated using three different immunological methods: double immunodiffusion, immunoelectrophoresis, and immunoblotting. Plasma of E2-treated males, in contrast to that of untreated males, shows sharp precipitin lines in a double immunodiffusion test when incubated with an antiserum raised against purified lamprey vitellin. Plasma samples of males and maturing females as well as vitellin purified from oocytes all form confluent precipitin lines without any spurs when diffusing in the same gel. Immunoelectrophoresis confirms these results. Immunoblotting of PAGE-separated plasma proteins with the anti-vitellin-antibody identifies protein bands at identical positions in the gel for both E2 -induced males and females. These bands are lacking in blood collected before the first hormone injection. All these results indicate immunological identity of vitelline, vitellogenin and the protein induced by E2-injection in males. This strongly suggests, that the latter is identical with vitellogenin. 1. Deeley RG, Mullinix KP, Wetekam W, Kronenberg HM, Meyers M, Eldridge JD, Goldberger RF; Biol Chem 1975; 250: 9060-9066; 2. Wallace RA; Biochim Biophys Acta 1970; 215: 176-183; 3. Kishida M, Anderson TR, Specker JL; Gen Comp Endocrinol 1992;88: 29-39.

Zurück zur Publikationsliste   Homepage Abt. 1