Synthesis of non-histone chromatin proteins of mice in spleen cells and myeloma cells RPC 5 and ABPC 22.

Non-histone chromatin proteins of myeloma cells RPC 5, synthesizing gamma 2A and ABPC 22 synthesizing IgM as well as non-histone chromatin proteins of spleen cells from mice bearing these tumours and from control mice were labelled during culture in vitro with 3H-tryptophan, 3H-leucine or 3H-methionine. Electrophoretic patterns of labelled chromatin proteins indicated, that in myeloma cells, producing spontaneously immunoglobulins, any characteristic fraction of non-histone chromatin proteins, described previously in immunoglobulin producing spleen cells, could not be detected, although the profiles of these proteins in myeloma cells, spleen cells from mice bearing these tumours and control spleen cells varied.