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Primary Endodermal Epithelial Cell Culture from the Yolk Sac Membrane of Japanese Quail Embryos
Published on: March 10, 2016
On the origin of the yolk protein ferritin in snails
Werner Bottke1, Monika Burschyk1, Jutta Volmer1
1Zoologisches Institut der Universität, Schlossplatz 5, D-4400, Münster, Federal Republic of Germany.
Abstract:
The iron storage protein, ferritin, is the major yolk protein in freshwater snails. In this report we show by in vitro labelling experiments that yolk ferritin of the snails Lymnaea stagnalis L. and Planorbarius corneus L. is an exogenous protein synthesized in the midgut gland and secreted into the hemolymph. Gonad and mantle tissue are inactive in the synthesis of yolk ferritin, but, together with the midgut gland, they synthesize another ferritin type (soma ferritin) which is not released into the hemolymph and which may be a housekeeping ferritin. Soma ferritin and yolk ferritin are not in a precursor/product relationship since subunits of both ferritins are synthesized as primary translation products in rabbit reticulocyte lysate programmed with poly (A)+ RNA from midgut gland and gonad. Results suggest that both ferritins are synthesized on different mRNAs (and possibly on different genes) so they may be regulated in a different way.
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