Molecular Mechanism of Magnetoreception

and ​Animal Navigation

Animals rely on senses to perceive the surrounding physical world. Magnetic sensing, or the ability to detect the Earth’s magnetic field (magnetoreception), is one of the most controversial animal senses. The notion that animals can detect the Earth’s magnetic field was once ridiculed, but is now a well-established fact. However, the nature of this enigmatic sense has remained a fascinating and unresolved biological mystery. For centuries, determining how animals can detect almost imperceptible gradients in Earth’s magnetic field and orient themselves has advanced slowly, making it one of the most challenging tasks in biology, or even in science in general.

Different from conventional approaches, we utilized a strategy that combined theoretical postulation, genome-wide screening, computational modeling and experimental validation in an attempt to reveal a fundamental mechanism for animal magnetic sensing. We have identified a magnetic receptor (designated as MagR) in animals and a rod-like protein complex magnetosensor. The magnetosensor system is a nano-scale biological compass consisting of photoreceptor Cryptochromes and magnetoreceptors, and has intrinsic magnetic polarity in alignment with magnetic fields, including the Earth’s geomagnetic field. 

The biocompass model of animal magnetoreception and navigation. a, A nanoscale Cry/MagR magnetosensor complex with intrinsic magnetic polarity and acts as light-dependent biocompass. Linear polymerization of Fe-S cluster-containing magnetoreceptors (MagRs) form a rod-like biocompass at the center (core, yellow), surrounded by photoreceptive cryptochromes (Crys, out layer, cyan). b, Cross section of a, electron transportation from FAD group in Cry to Fe-S cluster in MagR upon light stimulation may be possible. c, The biocompass model of magnetoreception. In animal navigation system, Cry/MagR magnetosensor complex may act as a biological compass to perceive information from earth’s geomagnetic field such as polarity, intensity and inclination.

The identification of magnetoreceptor (MagR) and the proposed Biocompass model have outlined a molecular mechanism of animal magnetoreception and navigation and opened a new window for exploration.

We are currently working on

- What is the origin of magnetic moments of MagR? 

- How the light- and magneto- perceptions are coupled in the Biocompass model? 

- Will MagR/Cry complex reassemble ‘molecular gyroscope’ or ‘‘quantum gyroscope’’? 

- How to apply magnetic fields to modulate biological processes based on MagR? 

The Structural Model of MagR/Cry Complex (Biocompass model). MagRs are colored yellow and orange to emphasize the double helical assembly. Crys are colored cyan.

Address

High Magnetic Field Laboratory

Hefei Institutes of Physical Science

Chinese Academy of Sciences 

Science Island, Hefei, China 230031

©2016 by Can Xie Lab