Lectin binding by crustacean cuticle: the cuticle of Callinectes sapidus throughout the molt cycle, and the intermolt cuticle of Procambarus clarkii and Ocypode quadrata

ABSTRACT Pieces of dorsal carapace from the crayfish Procambarus clarkii, the ghost crab Ocypode quadrata, and the blue crab Callinectes sapidus were fixed in Rossman's fluid or alcoholic Formalin, decalcified, paraffin-embedded, and probed with up to 21 fluorescein-conjugated lectins in order to determine the composition and distribution of their carbohydrate moieties. Unfixed, frozen sections were also employed. Tissue was examined from the crayfish and the ghost crab at intermolt (C4), and from the blue crab at premolt (all D stages), ecdysis, postmolt (all A and B stages, and stage C,) and intermolt. Different lectins showed different binding patterns at intermolt, but patterns of binding for individual lectins were consistent among the different species. A number of lectins showed different binding patterns at different stages of the molt cycle. Lectin binding was influenced by the method of fixation, with Rossman's-fixed tissue binding more lectins and more intensely. The overall pattern of lectin binding indicated that different carbohydrate moieties exist in the different layers of the integument, and that the availability of these lectin-binding sites may change over the molt cycle.