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PubMed · 7784186

Polyamines alter sequence-specific DNA-protein interactions.

C A Panagiotidis·S Artandi·K Calame·S J Silverstein
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Abstract

The polyamines are abundant biogenic cations implicated in many biological processes. Despite a plethora of evidence on polyamine-induced DNA conformational changes, no thorough study of their effects on the activities of sequence-specific DNA binding proteins has been performed. We describe the in vitro effects of polyamines on the activities of purified, representative DNA-binding proteins, and on complex protein mixtures. Polyamines at physiological concentrations enhance the binding of several proteins to DNA (e.g. USF, TFE3, Ig/EBP, NF-IL6, YY1 and ICP-4, a herpes simplex virus gene regulator), but inhibit others (e.g. Oct-1). The degree of enhancement correlates with cationic charge; divalent putrescine is ineffective whereas tetravalent spermine is more potent than trivalent spermidine. Polyamine effects on USF and ICP-4 result from increased rate of complex formation rather than a decreased rate of dissociation. DNAse I footprint analysis indicated that polyamines do not alter DNA-protein contacts. Polyamines also facilitate formation of complexes involving binding of more than one protein on a DNA fragment.

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Base SequenceCobaltDNADNA-Binding ProteinsHeLa CellsHerpesvirus 1, HumanHumansImmediate-Early ProteinsKineticsMolecular Sequence DataOligodeoxyribonucleotidesPolyaminesProtein BindingPutrescineRadiation-Sensitizing AgentsSpermidineSpermineSubstrate SpecificityComparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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C A Panagiotidis, S Artandi, K Calame, S J Silverstein. 1995-05-25. Polyamines alter sequence-specific DNA-protein interactions.. https://doi.org/10.1093/nar%2F23.10.1800

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