Cryptochrome 1 mediates light-dependent inclination magnetosensing in monarch butterflies
Wan G, Hayden AN, Iiams SE and others. Nature communications, February 2021.
Read the paper Free to read · doi:10.1038/s41467-021-21002-z
What this paper is about
Magnetic sensing is thought to work through quantum effects in cryptochrome proteins when light hits them. Evidence for that had come almost entirely from fruit flies.
This study shows the monarch's light-sensitive cryptochrome 1 mediates its inclination-based magnetic compass, extending the mechanism to an animal that uses it to migrate.
Summarised here from the abstract below. Not the authors’ words.
Abstract
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.
Abstract reproduced from the published paper, which is licensed CC BY. Copyright remains with the authors.
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title = {Cryptochrome 1 mediates light-dependent inclination magnetosensing in monarch butterflies (listing)},
author = {{Milkweed USA}},
year = {2026},
url = {https://milkweedusa.com/research/cryptochrome-1-mediates-light-dependent-inclination-magnetosensing-in-monarch-2021/},
note = {Accessed DATE}
}