TAILIEUCHUNG - Báo cáo khoa học: Polyamines interact with DNA as molecular aggregates Luciano D’Agostino1 and Aldo Di Luccia

New compounds, named nuclear aggregates of polyamines, havingamolecularmassof 8000, 4800and | Eur. J. Biochem. 269 4317-4325 2002 FEBS 2002 doi Polyamines interact with DNA as molecular aggregates Luciano D Agostino1 and Aldo Di Luccia2 1 Department of Clinical and Experimental Medicine Federico II University Naples Italy 2Institute of Food Science and Technology - National Research Council Avellino Italy New compounds named nuclear aggregates of polyamines having a molecular mass of8000 4800 and 1000 Da were found in the nuclear extracts of several replicating cells. Their molecular structure is based on the formation of ionic bonds between polyamine ammonium and phosphate groups. The production of the 4800 Da compound resulting from the aggregation of five or more 1000 Da units was increased in Caco-2 cells treated with the mitogen gastrin. Dissolving single polyamines in phosphate buffer resulted in the in vitro aggregation of polyamines with the formation of compounds with molecular masses identical to those of natural aggregates. After the interaction of the 4800 Da molecular aggregate with the genomic DNA at 37 C both the absorbance of DNA in phosphate buffer and the DNA mobility in agarose gel increased greatly. Furthermore these compounds were able to protect the genomic DNA from digestion by DNase I a phosphodiesterasic endonuclease. Our data indicate that the nuclear aggregate of polyamines interacts with DNA phosphate groups and influence more efficaciously than single polyamines both the conformation and the protection of the DNA. Keywords DNA conformation DNA protection apoptosis molecular aggregates polyamines. An increased intracellular concentration of polyamines is necessary for the activation of DNA synthesis and cell replication 1-4 . The intestinal replicating cells are particularly capable of accumulating polyamines promoting both their synthesis through the activation of the enzyme ornithine decarboxylase and their uptake from the extracellular space 5-9 . Caco-2 cells derived from a human colon .

• Báo cáo khoa học
• Report medicine
• traditional medicine
• scientific reports
• gastric cancer
• hormone medicine
• tumor cells
• medical knowledge
• medical research
• analysis of cytoplasmic
• oxidation
• Crystal structure
• bacteria
• hemoglobin
• medicine
• cell proliferation
• breast cancer
• chemical reaction
• biochemical studies
• environmental medicine