Studies on Physiological and Biochemical Properties of Female Specific Serum Protein and Its Immunocytochemical Localization in Carassius auratus cuvieri(Temminck Schlegel)

摘要

Female-specific serum protein(FSSP)is normally present in the sera of female fish,but it is notfound in males.However,estradiol benzoate(EB)was found to induce the appearance of FSSP inmale fish and immature female fish.Massive doses of FSSP caused a rapid increase in FSSP.Ultrastructural examination of the liver indicated an extensive proliferation of the rough endoplasmicreticulum and a decrease in glycogen and lipid droplets after EB injection.A preparative PAGE for isolating highly purified FSSP from the serum of EB-treated fish,Carassiusauratus cuvieri(Temminck & Schlegel),is described.Purified FSSP obtained from EB-induced O-crucian fish has a molecular weight of 466,000±4,000(n=10),while that in mature female serumis 480,000±40,000(n=2).FSSP appears to be a dimer,with the size of the possible monomerbeing 240,000±8,000(n=6).SDS-PAGE on gradient gels indicated that sera from males given multiple(12)injections of EBcontain a main band with a molecular weight of 147,000±6,000(n=6).However,the same serumsamples provided three bands of protein on the PAGE gels.Antiserum was raised against the electrophoretically purified FSSP.The resulting antibody formeda single,continuous precipitation line with sera from EB-treated males and vitellogenic females,butnot with that from normal males.lmmunocytochemistry(PAP method)was used to locate FSSP in the liver and ovary of maturefemales and the liver of EB-treated males.Strongly positive particles were found clustered in groupsaround liver cell nuclei under light microscopy,and the yolk granules in the oocytes were also filledwith positive particles.