Interactions between structure transitions in a torsionally constrained DNA.

Y Wang; W Sauerbier; M Blumenfeld

doi:10.1016/0006-291x(89)92777-0

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Interactions between structure transitions in a torsionally constrained DNA.

Y Wang·W Sauerbier·M Blumenfeld

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Abstract

We used S1 nuclease cleavage in conjunction with gel electrophoresis to evaluate torsion-induced cruciform extrusion at two inverted repeat sequences, IRS-B and IRS-C of plasmid pUC12. These structure transitions affect each other through competition for the available torsional free energy according to their relative energies of activation and the magnitude of DNA duplex unwinding associated with each transition. They can be modulated by the level of DNA negative torsion. Interplays between transition sequences occur over long distances and are independent of relative orientation of transition sites. DNA binding factors that enhance or repress structural transitions of specific sequences may, thus, regulate the structural and functional properties of torsionally coupled, distal sequences.

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Base Sequence DNA Electrophoresis, Agar Gel Endonucleases Hot Temperature Nucleic Acid Conformation Plasmids Repetitive Sequences, Nucleic Acid Single-Strand Specific DNA and RNA Endonucleases Thermodynamics Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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Y Wang, W Sauerbier, M Blumenfeld. 1989-02-15. Interactions between structure transitions in a torsionally constrained DNA.. https://doi.org/10.1016/0006-291x(89)92777-0

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