Correlation of patterns of nuclear protein synthesis with differentiation of mitogen-stimulated B-lymphocytes.

Nuclear proteins synthesised by mouse lymphocytes stimulated by the B-lymphocyte mitogen lipopolysaccharide have been analysed by 2-dimensional polyacrylamide gel electrophoresis. It has been shown that the rate of synthesis of both nucleoplasmic proteins and nonhistone chromatin proteins is stimulated dramatically by LPS and many nuclear proteins are synthesised that were undetectable in resting lymphocytes. The majority of these proteins are synthesised by lymphoblasts and plasma cells, the lymphocytes that remain small after LPS stimulation synthesizing relatively few proteins. Two chromatin proteins that have previously been shown to appear in the nucleus within 4h of mitogen stimulation exhibit a continuous increase in their rate of synthesis during lymphocyte differentiation. The possible roles of these proteins in differentiating lymphocytes are discussed.