标题:Selective effects of inhibitors of protein synthesis on metabolism of nuclear anc cytoplasmic proteins: evidence for coordinate synthesis of non-histone chromosomal proteins
期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1975
卷号:72
期号:11
页码:4450-4454
DOI:10.1073/pnas.72.11.4450
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:We have compared the effects of inhibitors of protein synthesis on the metabolism of nuclear and cytoplasmic proteins of HeLa S-3 cells. L-1-tosylamido-2-phenylethyl chloromethyl ketone, a potent inhibitor of polypeptide chain initiation, was shown to preferentially inhibit the synthesis of cytoplasmic proteins and of histones at concentrations that permit continued amino acid incorporation into nuclear non-histone proteins. Comparisons of the molecular weight distributions of newly synthesized proteins in the presence and absence of L-1-tosylamido-2-phenylethyl chloromethyl ketone have revealed striking differences between nuclear anc cytoplasmic protein fractions. Differential effects on the synthesis of cytoplasmic proteins, acid-soluble nuclear proteins, and residual nuclear proteins have also been obtained with the antibiotic, pactamycin, another inhibitor of polypeptide chain initiation. The incorporation of radioactive amino acids into nuclear non-histone proteins shows resistance to inhibition by pactamycin, but is strongly inhibited by agents such as puromycin and cycloheximide which block chain elongation. The possibility that proliferating cells have developed specialized mechanisms for the coordinate synthesis of chromosomal proteins, possibly involving polycistronic messenger RNAs, is tested and discussed.