Cryptochrome 1 mediates light-dependent inclination magnetosensing in monarch butterflies. Academic Article uri icon


  • Many animals use the Earth's geomagnetic field for orientation and navigation. Yet, the molecular and cellular underpinnings of the magnetic sense remain largely unknown. A biophysical model proposed that magnetoreception can be achieved through quantum effects of magnetically-sensitive radical pairs formed by the photoexcitation of cryptochrome (CRY) proteins. Studies in Drosophila are the only ones to date to have provided compelling evidence for the ultraviolet (UV)-A/blue light-sensitive type 1 CRY (CRY1) involvement in animal magnetoreception, and surprisingly extended this discovery to the light-insensitive mammalian-like type 2 CRYs (CRY2s) of both monarchs and humans. Here, we show that monarchs respond to a reversal of the inclination of the Earth's magnetic field in an UV-A/blue light and CRY1, but not CRY2, dependent manner. We further demonstrate that both antennae and eyes, which express CRY1, are magnetosensory organs. Our work argues that only light-sensitive CRYs function in animal light-dependent inclination-based magnetic sensing.

published proceedings

  • Nat Commun

altmetric score

  • 61.6

author list (cited authors)

  • Wan, G., Hayden, A. N., Iiams, S. E., & Merlin, C.

citation count

  • 26

complete list of authors

  • Wan, Guijun||Hayden, Ashley N||Iiams, Samantha E||Merlin, Christine

publication date

  • January 2021