Please use this identifier to cite or link to this item:
DC FieldValue
dc.titleTransition dynamics and selection of the distinct S-DNA and strand unpeeling modes of double helix overstretching
dc.contributor.authorFu, H.
dc.contributor.authorChen, H.
dc.contributor.authorZhang, X.
dc.contributor.authorQu, Y.
dc.contributor.authorMarko, J.F.
dc.contributor.authorYan, J.
dc.identifier.citationFu, H., Chen, H., Zhang, X., Qu, Y., Marko, J.F., Yan, J. (2011-04). Transition dynamics and selection of the distinct S-DNA and strand unpeeling modes of double helix overstretching. Nucleic Acids Research 39 (8) : 3473-3481. ScholarBank@NUS Repository.
dc.description.abstractRecent studies have revealed two distinct pathways for the DNA overstretching transition near 65 pN: 'unpeeling' of one strand from the other, and a transition from B-DNA to an elongated double-stranded 'S-DNA' form. However, basic questions concerning the dynamics of these transitions, relative stability of the two competing overstretched states, and effects of nicks and free DNA ends on overstretching, remain open. In this study we report that: (i) stepwise extension changes caused by sequence-defined barriers occur during the strand-unpeeling transition, whereas rapid, sequence-independent extension fluctuations occur during the B to S transition; (ii) the secondary transition that often occurs following the overstretching transition is strand-unpeeling, during which the extension increases by 0.01-0.02nm per base pair of S-DNA converted to single-stranded DNA at forces between 75 and 110 pN; (iii) even in the presence of nicks or free ends, S-DNA can be stable under physiological solution conditions; (iv) distribution of small GC-rich islands in a large DNA plays a key role in determining the transition pathways; and (v) in the absence of nicks or free ends, torsion-unconstrained DNA undergoes the overstretching transition via creation of S-DNA. Our study provides a new, high-resolution understanding of the competition between unpeeling and formation of S-DNA. © 2010 The Author(s).
dc.contributor.departmentMECHANOBIOLOGY INSTITUTE
dc.description.sourcetitleNucleic Acids Research
Appears in Collections:Staff Publications

Show simple item record
Files in This Item:
There are no files associated with this item.

Google ScholarTM



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.