A quantitative and qualitative study of proteins of the gonadal extract during growth and phases of reproductive activity in the snailHelix aspersa Müller.

The total soluble protein content in crude extracts of gonads ofHelix aspersa Müller from different stages of its life cycle was quantified and then resolved into different protein fractions using polyacrylamide gel electrophoresis. It was found that both the protein content and wet weight of the gonads increased during growth but decreased markedly during the copulation and egg-laying phases. Electrophoretic analysis of the extracts from different stages revealed that additional fractions progressively appeared and that in adults, the number and comcentration of the bands changed in response to physiological conditions (activity, copulation, egg-laying or hibernation) so that the maximum number of 27 fractions was observed during the active phase. We have attempted to correlate these biochemical observations with previously published descriptions of histological changes that occur during the development of the gonad.