POSTECDYSIAL CHANGES IN THE PROTEIN AND GLYCOPROTEIN COMPOSITION OF THE CUTICLE OF THE BLUE-CRAB CALLINECTES-SAPIDUS

Postecdysial modifications of the cuticle of Callinectes sapidus were evaluated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of soluble protein extracts. Gels stained with Coomassie b lue and with silver demonstrated that major changes in protein composi tion or mobility occurred immediately after ecdysis. Electroblots of S DS-PAGE gels were probed with various biotinylated lectins. The patter ns of lectin binding were also markedly different between blots of pre - and postecdysial cuticle extracts, demonstrating a change in glycosy lation or glycoprotein mobility in the early postecdysial period. The dramatic alteration in cuticular composition is concurrent with the on set of sclerotization and mineralization of the preexuvially deposited layers of the cuticle.