Summary: | 博士 === 國立臺灣大學 === 動物學系 === 81 === The resulte obtained from present study show that vitellin,
yolk protein, a glycolipoprotein derived from giant tiger
prawn, Penasue monodon, contain four polypeptides, Ep1, Ep2,
Ep3 and Ep4 with Mr 168, 104, 83 and 74 kDa respectively,
this protein was also purified using SDS-PAGE and gel-
elution. No cross reaction was observed among Ep2, Ep3
and Ep4 fractions of vitelin, However, antisura antiEp2
and AntiEp3 were demonstrated to be able to react with Ep1
fraction. The homogenates obtained from ripe ovaries and
hemolymph of vitellogenesis females showed an immuno-
identical pattern too those obtained from egg extracts. The
proteolysis mapping for each faction showed that Ep1, the
high molecular weight faction, conttains of Ep2 and
Ep3 fragments. These resulte may suggest that Epp1 is a
precursor of Ep2 and Ep3. Vitellogensis can be significantly
induced in the ovaries of the penaeid shrimp, Penaeus
monodon, by eyestalk ablation; 80% of shrimp were
spawing within 7 days after ablation. Using immuno-
fluorescence, it was observed that vittellin commences to
accumulate in the yolk globular stage oocytes. The
vitellin of atretic oocytes is re-absoted and transferred
to the newly matured oocytes. Four vitellin-like peptides
are synthesized in vitro by ovaries with Mr 220,168, 130 and 74
kDa respectively. Amongst them, 168 and 74 kDa peptides are
secreted into the culture medium. The results of immunostain
showed that, the anti-Ep antisera is able to react with the
ovary extracts of Penaeus japonicus. Each antiserum may
reactt to the compatible peptide of the P. monodon vitellin
peptied.
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