Chemical and structural analysis of a photoactive vertebrate cryptochrome from pigeon

Brian D. Zoltowski, Yogarany Chelliah, Anushka Wickramaratne, Lauren Jarocha, Nischal Karki, Wei Xu, Henrik Mouritsen, Peter J. Hore, Ryan E. Hibbs, Carla B. Green, Joseph S. Takahashi

Research output: Contribution to journalArticle

6 Scopus citations

Abstract

Computational and biochemical studies implicate the blue-light sensor cryptochrome (CRY) as an endogenous light-dependent magnetosensor enabling migratory birds to navigate using the Earth's magnetic field. Validation of such a mechanism has been hampered by the absence of structures of vertebrate CRYs that have functional photochemistry. Here we present crystal structures of Columba livia (pigeon) CRY4 that reveal evolutionarily conserved modifications to a sequence of Trp residues (Trp-triad) required for CRY photoreduction. In ClCRY4, the Trp-triad chain is extended to include a fourth Trp (W369) and a Tyr (Y319) residue at the protein surface that imparts an unusually high quantum yield of photoreduction. These results are consistent with observations of night migratory behavior in animals at low light levels and could have implications for photochemical pathways allowing magnetosensing.

Original languageEnglish (US)
Pages (from-to)19449-19457
Number of pages9
JournalProceedings of the National Academy of Sciences of the United States of America
Volume116
Issue number39
DOIs
StatePublished - Sep 24 2019

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Keywords

  • Cryptochromes
  • Magnetoreception
  • Photobiology

ASJC Scopus subject areas

  • General

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