Disintegration of cruciform and G-quadruplex structures during the course of helicase-dependent amplification (HDA). Issue 8 (15th April 2015)

• Record Type: Journal Article
• Authors: Li, Dawei; Lv, Bei; Zhang, Hao; Lee, Jasmine Yiqin; Li, Tianhu
• Is Part Of: Bioorganic & medicinal chemistry letters. Volume 25:Issue 8(2015)
• Page Start: 1709
• Page End: 1714
• Publication Date: 2015-04-15
• Subjects: Cruciform -- G-quadruplex -- Helicase -- Positive supercoiling -- DNA replication; Bioorganic chemistry -- Periodicals; Pharmaceutical chemistry -- Periodicals; 572
• DOI: 10.1016/j.bmcl.2015.02.070
• Languages: English
• ISSNs: 0960-894X

Abstract

Graphical abstract: It is demonstrated in our studies that positive supercoiling generated in HDA reaction can act as the driving force to disintegrate the cruciform and G-quadruplex structures. Abstract: Unlike chemical damages on DNA, physical alterations of B-form of DNA occur commonly in organisms that serve as signals for specified cellular events. Although the modes of action for repairing of chemically damaged DNA have been well studied nowadays, the repairing mechanisms for physically altered DNA structures have not yet been understood. Our current in vitro studies show that both breakdown of stable non-B DNA structures and resumption of canonical B-conformation of DNA can take place during the courses of isothermal helicase-dependent amplification (HDA). The pathway that makes the non-B DNA structures repairable is presumably the relieving of the accumulated torsional stress that was caused by the positive supercoiling. Our new findings suggest that living organisms might have evolved this distinct and economical pathway for repairing their physically altered DNA structures.