Prediction System for Dumbbell-Type Proteins: SOSUIdumbbell

A dumbbell-type (DT) protein comprises two globular domains and one helical segment connecting these globular domains. DT protein plays an important role in the regulation of other proteins. Calmodulin (CaM), a typical DT protein, for example, is a soluble calcium-binding protein that regulates several enzymes such as smooth muscle, myosin light-chain kinase and Ca2+/CaM-dependent protein kinase. By binding calcium ions, CaM changes its shape from elongated one to globular one and forms complexes with these enzymes [3]. Proteins revealed by genome analysis to have DT structure may turn out to be regulating proteins, and may have become therapeutic targets. Accurate prediction of DT proteins on the basis of physicochemical parameters, therefore, could prove to be an important aspect of analysis of open reading frames of genomes.