SANDERS, E.M.*; TERWILLIGER, N.B.; University of Oregon: Regulation of Hemocyanin and Cryptocyanin in adult Cancer magister

Several proteins in the hemocyanin gene family are involved in the crustacean molt cycle. Hemocyanin is a copper-containing respiratory pigment that reversibly binds oxygen. Structurally similar to hemocyanin, cryptocyanin lacks several copper-binding histidines. It likely originated from a hemocyanin gene duplication and has derived independent physiological roles. Previous research on the molt cycle of juvenile Cancer magister has shown cyclic patterns of hemocyanin and cryptocyanin regulation. Hemocyanin is always present in the hemolymph during the molt cycle. It increases in concentration during premolt and is reduced to low levels at ecdysis. Cryptocyanin is similar; however, it is present only during premolt in adults. The molt cycle of adult C. magister is much longer than that of juveniles and regulation of its respiratory proteins during this process has not been studied thoroughly. The molt cycle of juvenile instars lacks a clearly distinguishable intermolt phase and is virtually a repetition of premolt, ecdysis and postmolt events. Studying this process in adults will allow for clarification of respiratory protein dynamics during the transition periods between molts. We hypothesize the patterns of hemocyanin and cryptocyanin regulation of adult crabs will be proportional to that of juveniles but with a longer periodicity. To assess the regulation of these proteins in C. magister adults, we collected 15 adult male crabs in intermolt and premolt stages and maintained them in running seawater with adequate food. We sampled their hemolymph at regular intervals from intermolt to postmolt and quantified the proteins. Data will be presented on hemocyanin and cryptocyanin levels across the molt cycle of adults and compared with data on juvenile crabs. NSF 99-84202 to NBT.