Mechanical Cooperativity in DNA Cruciform Structures
نویسندگان
چکیده
منابع مشابه
Slow cruciform transitions in palindromic DNA.
Extrusion of cruciform structures in self-complementary regions of DNA is known to be favored by negative supercoiling of DNA. We show here that, in moderately supercoiled DNA, cruciform extrusion is a very slow process. In plasmid pUC7 DNA, with a 48-base-pair palindrome, the half-time of extrusion at 50 degrees C is typically several hours; rates are even slower at lower temperature. The rate...
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Sequence-dependent secondary DNA structures, such as cruciform or triplex DNA, are implicated in regulation of gene transcription and other important biological processes at the molecular level. Sequences capable of forming these structures can readily be identified in entire genomes by appropriate searching techniques. However, not every DNA segment containing the proper sequence has equal pro...
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This paper analyzes equilibrium superhelical cruciform formation in a topologial domain of DNA containing inverted repeat sequences. The cruciform conformation is shown to he stable when the molecule is sufficiently negatively supercoiled but not when it is positively supercoiled. For a particular sequence containing a single inverted repeat, onset of stability occurs at a degree of negative su...
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The paper presents measurements of the difference in the melting temperature of a colE1 DNA region when it is located inside the DNA helix and at its end. A direct comparison of calculations based on the rigorous theory of helix-coil transition with experimental data for .2 M Na+ (the conditions for fully reversible melting) yielded the value of 2.5-5x10(-5) for the cooperatively factor sigma. ...
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ژورنال
عنوان ژورنال: ChemPhysChem
سال: 2018
ISSN: 1439-4235,1439-7641
DOI: 10.1002/cphc.201800480