Δ Protein, a New Fibrous Protein of Skeletal Muscle: Properties

Abstract

Solutions of D protein contain a fibrous sub-fraction, Δ protein, whose presence is demonstrated by measurements of sedimentation rate, viscosity and flow birefringence. The presence of such a component is further indicated by fibrous material in electronmicrographs. Dissociation of the Δ protein molecule can be accomplished by lowering the ph. Reassociation occurs when the ph is raised. Possible relationships between Δ protein and tropomyosin are discussed. It seems possible that Δ protein may form the elastic filaments in the center of the sarcomere, recently described by several authors.