Protein synthetic patterns in immature and mature XXXX oocytes.

@entity1 @entity368 @entity535 @entity19 @entity1372 @entity95 @entity1853
A preliminary study of protein synthesis and @entity535 transport in @entity1 oocytes was initiated. Qualitative patterns or protein synthesis were examined in individual oocytes cultured in medium containing radiolabeled @entity1853 . The protein synthetic profile of immature oocytes, resolved by one-dimensional electrophoresis and fluorography, was observed to change markedly following germinal vesicle breakdown and oocyte maturation. No further differences in the one-dimensional protein synthetic patterns were observed in mature oocytes maintained in culture from 10 hours up to as long as 50 hours. The protein synthetic pattern of follicular cells was observed to be distinct from that of oocytes and was characterized by the predominant synthesis of a polypeptide with Mr = 44,000. Based on the specific activity of the @entity1853 precursor, the absolute rate of synthesis was calculated to be about 50 pg protein/oocyte/hour. Total protein content was measured to be about 150 ng/egg. Competition of @entity1853 uptake by @entity368 , efflux of radiolabeled @entity1853 from preloaded oocytes into medium containing @entity1853 and uptake of @entity1853 in medium with low @entity1372 ion concentration was observed. These findings are consistent with the presence of an L ( @entity368 -preferring) system for neutral @entity535 transport, similar to that in @entity19 and @entity95 eggs. These studies provide basic data for further analysis of oocytes and perhaps preimplantation-stage embryos in the future.
