Mapping nucleolar proteins with monoclonal antibodies.

Abstract

Using monoclonal antibodies as probes, 3 antigens were characterized with respect to localization in the nucleolus, MW and solubility. Two proteins, of 110,000 and 94,000 apparent MW, were associated with the ribonucleoprotein fibers. A 3rd protein, with a MW of 40,000, was accumulated at the nucleolar periphery, was present in the nucleoplasm, and may be involved in pre-ribosome maturation and transport.