Many animals use the Earth’s geomagnetic field to navigate long distance migrations, using information such as the strength and polarity of the field to inform them of where they are. For many years, there has been debate over how these animals are able to do this, with multiple theories suggested. A widely accepted theory is that a blue-light sensitive protein called Cryptochrome is responsible for this ‘sixth sense’, via a mechanism called the Radical Pair Mechanism. This theory describes a blue light dependent mechanism, where exposure to a magnetic field will push the system to form more of an active product, leading to downstream biological effects.
Although Cryptochrome is without doubt a part of this system, data has arisen in the last decade to suggest that this isn’t the whole story and the widely accepted hypothesis needs updating.
Delivered through a collaboration between the National Physical Laboratory and the University of Manchester, this PhD project uses the fruit fly, Drosophila melanogaster, to investigate the cellular signalling which occurs to mediate the effects of Cryptochrome.
This project has shown that the last 52 amino acids appear to be responsible for signalling magnetic field effects, while an associated light sensitive cofactor may act as a ‘magnetosensor’.
Understanding the fundamental and widely debated question of magnetosensitivity will help answer the longstanding question of how animals can detect magnetic fields. There are potential impacts of this work on human health, and it presents the potential to harness magnetosensitivity to develop new laboratory tools, such as those to control cellular activity.