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Published online: 27 May 2009 | doi:10.1038/nchina.2009.116
Biomimetics: Mimicking the potassium channel
Felix Cheung
Abstract
Researchers in Beijing have created an artificial system that mimics the way potassium channels open or close in response to changes in ion concentration
Original article citation
et al. A biomimetic potassium responsive nanochannel: G-quadruplex DNA conformational switching in a synthetic nanopore. J. Am. Chem. Soc.doi:10.1021/ja901574c (2009).
Introduction
© (2009) ACS
Potassium channels are the most widely distributed type of ion channel in the human body. They modulate the activity of muscle and nerve cells by allowing the movement of potassium ions across the cell membrane. In Beijing, a team of researchers led by Lei Jiang at the Chinese Academy of Sciences, Dongsheng Liu at the National Center for Nanoscience and Nanotechnology and Yugang Wang at Peking University1 has developed a system of synthetic nanopores that mimics potassium channels. The system is unique because the nanopores respond to changes in ion concentration — just like the biological potassium channels.
The researchers had previously developed a DNA–nanopore system that responds to pH changes2. This time, they attached G-quadruplex DNAs onto the inner surface of the nanopore (pictured). When there is no potassium ion present, G-quadruplex DNAs relax to loosely packed single-stranded structures. When potassium ions are present, however, they fold into densely packed rigid structures, which partly reduces the effective pore size of the nanopore.
The pore size — and therefore the flow of potassium ions — changes as the ion concentration changes. The situation closely resembles that observed in potassium channels in vivo. The researchers believe the artificial system can be used to simulate the process of ion transport in living organisms, and might even be used to make bio-inspired intelligent machines.
The authors of this work are from:
Center of Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China; National Center for Nanoscience and Nanotechnology, Beijing, China; State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing, China.
References
- Hou, X. et al. A biomimetic potassium responsive nanochannel: G-quadruplex DNA conformational switching in a synthetic nanopore. J. Am. Chem. Soc.
doi:10.1021/ja901574c (2009). | Article | - Xia, F. et al. Gating of single synthetic nanopores by proton-driven DNA molecular motors. J. Am. Chem. Soc. 130, 8345–8350
(2008). | Article | PubMed | ChemPort |
