Electrophoresis of acid soluble proteins from rat liver nuclei and polysomes on large two-dimensional polyacrylamide gels.

Increased resolution of 0.4 N H(2)SO(4) soluble rat liver polysomal and nuclear proteins was achieved by initial electrophoresis on 15 percent polyacrylamide disc gels (25 times 0.5 cm) followed by electrophoresis on 16 percent polyacrylamide gel slabs (25 times 15 cm). With this method, it was found that the histones were resolved into 12 spots, the polysomal proteins A1 and A9 were each resolved into two components, and polysomal proteins A1, A1 and A1 with molecular weights of approximately 14,000 were separated from the other proteins by their rapid migration in the first dimension. Moreover, no histones were found in the acid extracts of the polysomes.