[Nuclear proteins of stimulated lymphocytes (author's transl)]

Lymphocytes activated by phytohaemagglutinin (PHA) change from a resting state (GO) to an actively growing one (G1). To investigate the role of growth regulatory protein in this process we have determined the patterns of synthesis of acidic (non-histone, NHCP) and basic (histone) nuclear chromatin proteins, and of cytoplasmic proteins during PHA activation of human lymphocytes, Protein fractions isolated from a mixture of stimulated (pulse-labelled with 14C leucine) and unstimulated (labelled with 3H-leucine) lymphocytes were separated on SDS-polyacrylamide gel electrophoresis and the ratio of 14C/3H determined on 1 mm gel slices. Several peaks of increased synthesis of specific peptides are detected in all fractions within 12 h of activation. When activation is blocked by an amino acid deficiency, the pattern of label upon release of the inhibition by addition of the missing amino acid is different from that of uninhibited lymphcytes.