title: Incorporation of various amino acids into non-histone chromatin protein fractions of spleen cells of mice immunized with IgG.
abstract: Incorporation of three various amino acids ([3H]-tryptophan, [3H]-methionine or [3H]-leucine) into the non-histone chromatin proteins, synthesized in spleen cells of mice after immunization with IgG, is described. Two new fractions of non-histone chromatin proteins (I-mol. wt. below 3 000 and B1-mol. wt. about 120 000), appearing during the immune reaction were labelled with [3H]-tryptophan and [3H]-methionine but not with [3H]-leucine. Synthesis of these fractions was observed only at the time of maximal RNA synthesis. A suggestion about the role of tryptophan and methionine in non-histone chromatin proteins in the regulatory processes of gene activation is discussed on the basis of their selective binding to DNA.
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D002868:Chromosomal Proteins, Non-Histone / Q000096:biosynthesis / Q000276:immunology*; D007074:Immunoglobulin G / Q000276:immunology*; D007930:Leucine / Q000378:metabolism; D008715:Methionine / Q000378:metabolism; D051379:Mice; D008970:Molecular Weight; D012313:RNA / Q000096:biosynthesis; D013154:Spleen / Q000276:immunology / Q000378:metabolism*; D014364:Tryptophan / Q000378:metabolism
chemical_list: D000596:Amino Acids; D002868:Chromosomal Proteins, Non-Histone; D007074:Immunoglobulin G; D012313:RNA; D014364:Tryptophan; D008715:Methionine; D007930:Leucine