Charge Neutralization Drives the Shape Reconfiguration of DNA Nanotubes. (26th March 2018)

• Record Type: Journal Article
• Authors: Liu, Pi; Zhao, Yan; Liu, Xiaoguo; Sun, Jixue; Xu, Dede; Li, Yang; Li, Qian; Wang, Lihua; Yang, Sichun; Fan, Chunhai; Lin, Jianping
• Is Part Of: Angewandte Chemie. Volume 130:Number 19(2018)
• Page Start: 5516
• Page End: 5520
• Publication Date: 2018-03-26
• Subjects: DNA-Nanotechnologie -- Formerkennung -- Molekulare Kanäle -- Moleküldynamik -- SAXS; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.201801498
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Reconfiguration of membrane protein channels for gated transport is highly regulated under physiological conditions. However, a mechanistic understanding of such channels remains challenging owing to the difficulty in probing subtle gating‐associated structural changes. Herein, we show that charge neutralization can drive the shape reconfiguration of a biomimetic 6‐helix bundle DNA nanotube (6HB). Specifically, 6HB adopts a compact state when its charge is neutralized by Mg 2+ ; whereas Na + switches it to the expanded state, as revealed by MD simulations, small‐angle X‐ray scattering (SAXS), and FRET characterization. Furthermore, partial neutralization of the DNA backbone charges by chemical modification renders 6HB compact and insensitive to ions, suggesting an interplay between electrostatic and hydrophobic forces in the channels. This system provides a platform for understanding the structure–function relationship of biological channels and designing rules for the shape control of DNA nanostructures in biomedical applications.