VITELLOGENIC FERRITIN OF LYMNAEA-STAGNALIS L (MOLLUSCA, GASTROPODA) DIFFERS IN STRUCTURE FROM SOMA CELL TYPE FERRITIN

The 2 major polypeptides of snail ferritin with apparent MW of 19,000 and 24,000 were purified by sodium dodecylsulfate [SDS] electrophoresis and characterized by amino acid analysis and 1-dimensional fingerprinting following cleavage of the chains with cyanogen bromide and analysis of the fragments on SDS gels. Both chains show a similar overall amino acid composition, but are distinct in Ile content. Both differ in pattern of peptides generated by CNBr cleavage. The results suggest a different primary structure for the ferritins obtained from somatic tissue and the oocytes of snails and are in favor of a yolk specific ferritin type.