Possible magneto-mechanical and magneto-thermal mechanisms of ion channel activation in magnetogenetics
The palette of tools for perturbation of neural activity is continually expanding. On the forefront of this expansion is magnetogenetics, where ion channels are genetically engineered to be closely coupled to the iron-storage protein ferritin. Initial reports on magnetogenetics have sparked a vigorous debate on the plausibility of physical mechanisms of ion channel activation by means of external magnetic fields. The criticism leveled against magnetogenetics as being physically implausible is based on the specific assumptions about the magnetic spin configurations of iron in ferritin. I consider here a wider range of possible spin configurations of iron in ferritin and the consequences these might have in magnetogenetics. I propose several new magneto-mechanical and magneto-thermal mechanisms of ion channel activation that may clarify some of the mysteries that presently challenge our understanding of the reported biological experiments. Finally, I present some additional puzzles that will require further theoretical and experimental investigation.
All results in this study are either theoretical calculations or numerical calculations.
Article and author information
Howard Hughes Medical Institute
- Mladen Barbic
Howard Hughes Medical Institute
- Mladen Barbic
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- David Kleinfeld, University of California, San Diego, United States
- Received: February 5, 2019
- Accepted: July 28, 2019
- Accepted Manuscript published: August 2, 2019 (version 1)
- Version of Record published: August 14, 2019 (version 2)
© 2019, Barbic
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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