HEPATOPANCREAS OF PARATELPHUSA HYDRODROMOUS (HERBST): HISTOPHYSIOLOGY AND THE PATTERN OF PROTEINS IN RELATION TO REPRODUCTION AND MOLT

¹ Department of Zoology, Calicut University, Kerala, S. India

1. Protein level in the hepatopancreas of Paratelphusa is low even in intermolt. A total of 5 protein fractions (H-1 to H-5) could be detected under acidic conditions of disc electrophoresis. They are homologous to P-2, P-7, P-8, P-9 and P-12 of the plasma, and OV-2, OV-6, OV-7, OV-8 and OV-10 of the ovary, respectively, in their mobilities. None of the major vitellogenins including the plasma sex protein, which contributes significantly to yolk formation, is either synthesized or stored as such in the hepatopancreas. The increase in the levels of fraction H-3 with vitellogenesis, and the fact that fractions H-2 and H-4 appear in adult females only in relation to specific stages in the ovarian cycle, however, suggest that these proteins may play some role in vitellogenesis, as enzymes, carrier proteins or fuels.

2. Eyestalk removal causes in juvenile and adult females of Paratelphusa the addition of fractions H-1 H-2 and also H-4 to fractions H-3 and H-5 already present. The synthesis of the proteins in the hepatopancreas related to molt and reproduction appears to be normally inhibited during the intermolt by some eyestalk principle.