Summary
FeRIC (Ferritin iron Redistribution to Ion Channels) is a magnetogenetic technique that uses radio frequency (RF) alternating magnetic fields to activate the transient receptor potential channels, TRPV1 and TRPV4, coupled to cellular ferritins. In cells expressing ferritin-tagged TRPV, RF stimulation increases the cytosolic Ca2+ levels via a biochemical pathway. The interaction between RF and ferritin increases the free cytosolic iron levels that in turn, trigger chemical reactions producing reactive oxygen species and oxidized lipids that activate the ferritin-tagged TRPV. In this pathway, it is expected that experimental factors that disturb the ferritin expression, the ferritin iron load, the TRPV functional expression, or the cellular redox state will impact the efficiency of RF in activating ferritin-tagged TRPV. Here, we examined several experimental factors that either enhance or abolish the RF control of ferritin-tagged TRPV. The findings may help optimize and establish reproducible magnetogenetic protocols.
Competing Interest Statement
C.L. shares ownership of a patent application (WO2016004281 A1 PCT/US2015/038948) relating to the use of FeRIC for cell modulation and treatments. All other authors declare that they have no competing interests.
Footnotes
Ca2+ imaging results: updated to include the traces of GCAMP6 fluorescence from all imaged cells. Results section I: updated to include Ca2+ imaging experiments at different temperatures. Results section II: updated to include experiments using different iron sources to increase cellular iron import.