Membrane D2 T antigen: characterization and comparison with its nuclear counterpart

Abstract

Up to 40% of membrane T antigen (D2 T antigen) produced by the adenovirus 2–simian virus 40 hybrid, Ad2+D2, remained tightly associated with membranes under alkaline conditions up to pH 11.5. The antigen could not be totally solubilized by treatment with ionic detergents, nonionic detergents, or both. These properties are characteristic of integral membrane proteins. Sephacryl S-300 chromatography in high salt in the presence of Brij-99 showed that the nuclear form of D2 T antigen was dissociated to low molecular weight species, while the membrane form eluted as a complex of high molecular weight. The membrane form, therefore, is able to bind more detergent than the nuclear form, indicating a difference in supramolecular structure.