RESUMO
DNA and nuclear RNA fractions contain small peptides (mol. wt. 600-1500) attached noncovalently. A large scale isolation procedure was developed for the extraction of such peptides directly from the lysed nuclei. Further purification and fractionation was performed with the chromatography on Sephadex, silica gel and H.P.L.C. C18 reverse phase columns. H.P.L.C. fractionation yielded eleven peaks. The peptides are rich in serine, glycine, alanine and acidic amino acids. They do not contain sulfur-containing amino acids. Only occasionally tyrosine, phenyalanine, histidine, arginine, and very moderate amount of lysine are found. These peptides are active in inhibiting gene expression in cell-free systems and incorporation of labeled thymidine in L 1210 murine leukemic cell culture. Thorough and exhaustive analysis demonstrated that the isolated peptides are not degradative products of histone or nonhistone chromosomal proteins.
Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/ultraestrutura , Peptídeos/isolamento & purificação , Aminoácidos/análise , Animais , Bovinos , Núcleo Celular/análise , Sistema Livre de Células , Fracionamento Químico , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , DNA/metabolismo , DNA Polimerase I/metabolismo , Replicação do DNA/efeitos dos fármacos , Peso Molecular , Peptídeos/metabolismo , Peptídeos/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos , RNA/metabolismo , Transcrição Gênica/efeitos dos fármacosRESUMO
DNA and nuclear RNA fractions contain small peptides (mol. wt. 600 - 1500) attached noncovalently. A large scale isolation procedure was developed for the extraction of such peptides directly from the lysed nuclei. Further purification and fractionation was performed with the chromatography on Sephadex, silica gel and h.p.l.c. C18 reverse phase columns. H.p.l.c. fractionation yielded eleven peaks. The peptides are rich in serine, glycine, alanine and acidic amino acids. They do not contain sulphur-containing amino acids. Only occasionally tyrosine, phenylalanine, histidine, arginine, and very moderate amount of lysine are found. These peptides are active in inhibiting gene expression in cell-free systems and incorporation of labeled thymidine in L 1210 murine leukemic cell culture. Thorough and exhaustive analysis demonstrated that the isolated peptides are not degradative products of histone or nonhistone chromosomal proteins.
