Insects must periodically secrete a new cuticular exoskeleton and shed the old confining one to complete development to the adult stage. Tanning or sclerotization of the new cuticle with catecholamine metabolites, hardens selected regions of the exoskeleton for protection, locomotion and a diversity of other vital functions. This project focuses on identifying the reactive catecholamine metabolites or tanning agents and determining how they interact with the structural polymers of protein and chitin to form the hardened exoskeleton. The new non-destructive technique of solid-state NMR is being used to determine how the structural molecules are linked together by catecholamine metabolites to produce a cuticle with unique mechanical properties. The PIs also are characterizing the enzymes that are necessary for regulating cuticle tanning and the action of potential enzyme inhibitors of the process. The disruption of any step in the sequence can block further development and consequently may provide highly selective approaches to insect pest control.//
