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Twisting of DNA Origami from Intercalators.

ABSTRACT: DNA nanostructures represent the confluence of materials science, computer science, biology, and engineering. As functional assemblies, they are capable of performing mechanical and chemical work. In this study, we demonstrate global twisting of DNA nanorails made from two DNA origami six-helix bundles. Twisting was controlled using ethidium bromide or SYBR Green I as model intercalators. Our findings demonstrate that DNA nanorails: (i) twist when subjected to intercalators and the amount of twisting is concentration dependent, and (ii) twisting saturates at elevated concentrations. This study provides insight into how complex DNA structures undergo conformational changes when exposed to intercalators and may be of relevance when exploring how intercalating drugs interact with condensed biological structures such as chromatin and chromosomes, as well as chromatin analogous gene expression devices.

SUBMITTER: Zadegan RM

PROVIDER: S-EPMC5547094 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Twisting of DNA Origami from Intercalators.

Zadegan Reza M RM Lindau Elias G EG Klein William P WP Green Christopher C Graugnard Elton E Yurke Bernard B Kuang Wan W Hughes William L WL

Scientific reports 20170807 1

DNA nanostructures represent the confluence of materials science, computer science, biology, and engineering. As functional assemblies, they are capable of performing mechanical and chemical work. In this study, we demonstrate global twisting of DNA nanorails made from two DNA origami six-helix bundles. Twisting was controlled using ethidium bromide or SYBR Green I as model intercalators. Our findings demonstrate that DNA nanorails: (i) twist when subjected to intercalators and the amount of twi ...[more]

PMID: 28785065

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