DOI: 10.1073/pnas.69.1.143. An Activity from Mammalian Cells That Untwists Superhelical DNA

An Activity from Mammalian Cells That Untwists Superhelical DNA—A Possible Swivel For DNA Replication

10.1073/pnas.69.1.143

Crossref journal-article

Proceedings of the National Academy of Sciences

Proceedings of the National Academy of Sciences (341)

Abstract

Nuclei from secondary mouse-embryo cells contain an activity capable of untwisting closed-circular DNAs containing either negative or positive superhelical turns. The activity has no apparent effect on a closed-circular DNA containing no superhelical turns, and is not due to the combined action of an endonuclease and polynucleotide ligase. The enzyme apparently acts by introducing a single-strand nick into the DNA, forming a DNA-enzyme complex that allows the strands to rotate relative to the helix axis before reversing the reaction and sealing the break. The enzyme might possibly serve as a swivel during DNA replication.

Bibliography

Champoux, J. J., & Dulbecco, R. (1972). An Activity from Mammalian Cells That Untwists Superhelical DNAâA Possible Swivel For DNA Replication. Proceedings of the National Academy of Sciences, 69(1), 143â146.

Authors 2

James J. Champoux (first)
Renato Dulbecco (additional)

References 0 Referenced 224

None

Dates

Type	When
Created	19 years, 3 months ago (May 31, 2006, 2:30 a.m.)
Deposited	3 years, 4 months ago (April 13, 2022, 10:21 a.m.)
Indexed	1 week, 1 day ago (Aug. 28, 2025, 8:26 a.m.)
Issued	53 years, 8 months ago (Jan. 1, 1972)
Published	53 years, 8 months ago (Jan. 1, 1972)
Published Online	53 years, 8 months ago (Jan. 1, 1972)
Published Print	53 years, 8 months ago (Jan. 1, 1972)

Funders 0

None

BibTeX

@article{Champoux_1972, title={An Activity from Mammalian Cells That Untwists Superhelical DNA—A Possible Swivel For DNA Replication}, volume={69}, ISSN={1091-6490}, url={http://dx.doi.org/10.1073/pnas.69.1.143}, DOI={10.1073/pnas.69.1.143}, number={1}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Champoux, James J. and Dulbecco, Renato}, year={1972}, month=jan, pages={143–146} }

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