1. Physics of Living Systems
  2. Neuroscience

Physical limits to magnetogenetics

  1. Markus Meister  Is a corresponding author
  1. California Institute of Technology, United States
https://doi.org/10.7554/eLife.17210
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  1. Markus Meister
(2016)
Physical limits to magnetogenetics
eLife 5:e17210.
https://doi.org/10.7554/eLife.17210
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Abstract

This is an analysis of how magnetic fields affect biological molecules and cells. It was prompted by a series of prominent reports regarding magnetism in biological systems. The first claims to have identified a protein complex that acts like a compass needle to guide magnetic orientation in animals (Qin et al., 2016). Two other articles report magnetic control of membrane conductance by attaching ferritin to an ion channel protein and then tugging the ferritin or heating it with a magnetic field (Stanley et al., 2015; Wheeler et al., 2016). Here I argue that these claims conflict with basic laws of physics. The discrepancies are large: from 5 to 10 log units. If the reported phenomena do in fact occur, they must have causes entirely different from the ones proposed by the authors. The paramagnetic nature of protein complexes is found to seriously limit their utility for engineering magnetically sensitive cells.

Article and author information

Author details

  1. Markus Meister

    Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States
    For correspondence
    meister@caltech.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2136-6506

Funding

No external funding was received for this work.

Copyright

© 2016, Meister

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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  1. Markus Meister
(2016)
Physical limits to magnetogenetics
eLife 5:e17210.
https://doi.org/10.7554/eLife.17210

Share this article

https://doi.org/10.7554/eLife.17210

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Further reading

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