For decades we have known that a wide variety of animals use the earth’s magnetic field for navigation, although the means by which they sense it has remained a mystery. There is a long-standing idea that animals like migratory birds use small magnetic deposits in their beaks to act as a compass, however, this idea remains unverified and is currently questioned by many in the field. Recently, an alternative idea was proposed: that a light-sensitive protein found in the eyes of many animals, from insects to humans, could act as a chemical detector of the earth’s magnetic field. Subsequent work in the fruit fly has also shown that this protein is required for some aspects of magnetic field perception.
In my research, I propose to use the fruit fly to further investigate the mechanisms of chemical magnetic field detection, from the fly’s capacity to sense magnetic fields on a molecular level, to how this sensation occurs on a cellular level in the fly. Fruit flies are ideal candidates for this work as they have already been established as being sensitive to magnetic fields, they are easily manipulated on a genetic level, and there is a large set of tools available for monitoring and altering their brains. By placing fruit flies in controllable magnetic fields, I can then monitor responses in the brains of live animals in order to determine which cells respond to magnetic fields. The identified cells can then be individually altered to determine how different proteins contribute to the detection of magnetic fields.
These experiments will shed light on a long-standing question in neuroscience: how do animals detect magnetic fields? Additionally, the characterization of magnetically sensitive proteins will lay the groundwork for the development of a new class of brain stimulators that respond to magnetic fields. These would have a significant advantage over current methods, which often require invasive surgery and implants to function in live animals. In contrast, magnetic field-based neural activators could easily penetrate tissue and provide a non-invasive means of brain stimulation.