Subsecond multichannel magnetic control of select neural circuits in freely moving flies

Here the authors describe a method for remote magnetothermal stimulation of neurons that achieves subsecond behavioural responses in Drosophila fruit flies by combining magnetic nanoparticles with TRPA1-A, a rate-sensitive thermoreceptor. Tuning the properties of magnetic nanoparticles to respond to different magnetic field strengths and frequencies enables multichannel thermal magnetogenetic stimulation. Precisely timed activation of genetically targeted cells is a powerful tool for the study of neural circuits and control of cell-based therapies. Magnetic control of cell activity, or 'magnetogenetics', using magnetic nanoparticle heating of temperature-sensitive ion channels enables remote, non-invasive activation of neurons for deep-tissue applications and freely behaving animal studies. However, the in vivo response time of thermal magnetogenetics is currently tens of seconds, which prevents precise temporal modulation of neural activity. Moreover, magnetogenetics has yet to achieve in vivo multiplexed stimulation of different groups of neurons. Here we produce subsecond behavioural responses in Drosophila melanogaster by combining magnetic nanoparticles with a rate-sensitive thermoreceptor (TRPA1-A). Furthermore, by tuning magnetic nanoparticles to respond to different magnetic field strengths and frequencies, we achieve subsecond, multichannel stimulation. These results bring magnetogenetics closer to the temporal resolution and multiplexed stimulation possible with optogenetics while maintaining the minimal invasiveness and deep-tissue stimulation possible only by magnetic control.

Automated summary

The authors describe a method for remote magnetothermal stimulation of neurons in fruit flies, achieving subsecond behavioral responses by combining magnetic nanoparticles with a thermoreceptor. By tuning the properties of magnetic nanoparticles, multichannel thermal magnetogenetic stimulation can be achieved. This technique allows precise activation of targeted cells, enabling the study of neural circuits and cell-based therapies. It offers a non-invasive and deep-tissue method for remote control of cell activity, bringing magnetogenetics closer to the temporal resolution and multiplexed stimulation achieved with optogenetics.