title: Studies on nuclear deprimerones: isolation, fractionation, characterization and control of gene expression.
abstract: A procedure was developed for the isolation of low molecular weight peptides (deprimerones) from calf thymus nuclei and other tissues. These peptides are active in controlling transcription and translation in cell-free systems, and stabilize the double stranded structure of DNA. The procedure involves extraction of nuclei with 80% ethanol at pH 9.5 and fractionation of the extracted peptides on Sephadex G-25. The isolated deprimerones represent heterogenous peptidic fractions which can be separated into four activity peaks on Sephadex G-25 column and into ten peptidic spots on two-dimensional cellulose gel thin layer chromatography. One of the peaks is identical to a chromatin peptidic fraction isolated previously by binding to DNA-cellulose. The deprimerones contain about 8 or 9 different amino acids. It was demonstrated that the cytoplasm contains about 10% of the deprimerones present in nuclei. They are also ubiquitous, since they were found in each of the tissues studied: calf thymus, mouse thymus, mouse spleen and mouse liver.
mesh_terms: D000818:Animals; D002417:Cattle; D002467:Cell Nucleus / Q000032:analysis; D051379:Mice; D008970:Molecular Weight; D010455:Peptides / Q000302:isolation & purification* / Q000378:metabolism; D014176:Protein Biosynthesis; D013950:Thymus Gland / Q000032:analysis; D014158:Transcription, Genetic
chemical_list: D010455:Peptides; C021657:deprimerones