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Poly(ADP-ribose) polymerase forms loops with DNA.

G Gradwohl·A Mazen·G de Murcia
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Abstract

The interaction between highly purified poly(ADP-ribose) polymerase from calf thymus and different topological forms of pBR322 DNA has been studied by gel retardation electrophoresis and electron microscopy. We show that: (i) in the absence of nicks on DNA the enzyme has a marked affinity for supercoiled (form I) DNA, (ii) in the presence of single stranded breaks poly(ADP-ribose) polymerase preferentially binds to form II, (iii) in all cases enzyme molecules are frequently located at DNA intersections, (iv) a cooperative binding of the enzyme on DNA occurs.

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DNADNA, SuperhelicalDNA-Binding ProteinsElectrophoresisIn Vitro TechniquesMicroscopy, ElectronNucleic Acid ConformationPoly(ADP-ribose) PolymerasesSubstrate SpecificityJournal Article

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G Gradwohl, A Mazen, G de Murcia. 1987-11-13. Poly(ADP-ribose) polymerase forms loops with DNA.. https://doi.org/10.1016/s0006-291x(87)80219-x

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