Capturing structural intermediates in an animal-like cryptochrome photoreceptor by time-resolved crystallography
Animal-like cryptochromes are photoreceptors that control circadian rhythm and signaling in many eukaryotes. Transient photoreduction of the cryptochrome flavin chromophore initiated signaling via a poorly understood mechanism. By serial femtosecond crystallography (SFX), we show that the photoreduction mechanism of <i>Chlamydomonas reinhardtii</i> cryptochrome involves three loci [carboxyl-terminal region, a transient protonation pathway, and flavin adenine dinucleotide (FAD)-binding site] acting in unison to accomplish three effects: radical pair stabilization, protonation of FAD radical, and formation of the signaling state. Using 19 time-resolved SFX snapshots between 10 nanoseconds and 233 milliseconds, we found that light-driven FAD<sup>•-</sup>/tyrosyl-373 radical pair (RP) formation primes α22 unfolding. Electron transfer-dependent protonation of aspartate-321 by tyrosine-373 is the epicenter of unfolding by disrupting salt bridges between α22 and the photolyase homology region. Before helix unfolding, another pathway opens transiently for FAD<sup>•-</sup> protonation and RP stabilization. This link between RP formation and conformational changes provides a structural basis for signaling by animal-like cryptochromes.
Authors
- So Iwata (ORCID: https://orcid.org/0000-0003-1735-2937)
- Manuel Maestre‐Reyna (ORCID: https://orcid.org/0000-0002-9566-7216)
- Jungmin Kang (ORCID: https://orcid.org/0000-0002-3506-6400)
- Cheng‐Chung Lee (ORCID: https://orcid.org/0000-0002-8259-4388)
- Antoine Royant (ORCID: https://orcid.org/0000-0002-1919-8649)
- Stephan Kiontke (ORCID: https://orcid.org/0000-0001-5822-913X)
- Yasufumi Umena
- Yasumasa Joti (ORCID: https://orcid.org/0000-0002-4040-5972)
- Takehiko Tosha (ORCID: https://orcid.org/0000-0002-8971-0759)
- Eriko Nango (ORCID: https://orcid.org/0000-0001-9851-7355)
- Martin Saft (ORCID: https://orcid.org/0000-0003-3943-2786)
- Yuki Ban (ORCID: https://orcid.org/0000-0001-7349-6383)
- Tomoyuki Tanaka (ORCID: https://orcid.org/0000-0002-9886-5947)
- Fangjia Luo (ORCID: https://orcid.org/0000-0003-0631-6236)
- Eka Putra Gusti Ngurah Putu (ORCID: https://orcid.org/0000-0003-1658-4015)
- Nicolas Caramello (ORCID: https://orcid.org/0000-0003-0025-0213)
- Lars‐Oliver Essen (ORCID: https://orcid.org/0000-0003-4272-4026)
- Wei‐Cheng Huang (ORCID: https://orcid.org/0000-0003-4437-3530)
- Junpei Yamamoto (ORCID: https://orcid.org/0000-0002-5036-991X)
- Sylvain Engilberge (ORCID: https://orcid.org/0000-0001-8680-6790)
- Motoki Nakamura
- Cheng‐Han Yang (ORCID: https://orcid.org/0000-0001-7517-3799)
- Kensuke Tono (ORCID: https://orcid.org/0000-0003-1218-3759)
- Po‐Hsun Wang (ORCID: https://orcid.org/0000-0001-7359-934X)
- Hsiang-Yi Wu (ORCID: https://orcid.org/0000-0001-5449-8295)
- Yuhei Hosokawa (ORCID: https://orcid.org/0000-0001-9559-8567)
- Rie Tanaka (ORCID: https://orcid.org/0000-0003-1062-4792)
- Sophie Franz-Badur (ORCID: https://orcid.org/0000-0002-6613-7742)
- Shigeki Owada (ORCID: https://orcid.org/0000-0002-1451-7612)
- Yao-Kai Chang (ORCID: https://orcid.org/0000-0003-0314-3165)
- Takeshi Imura (ORCID: https://orcid.org/0000-0002-6762-4980)
- Yoshitaka Bessho (ORCID: https://orcid.org/0000-0001-9297-7473)
- Lukas Korf (ORCID: https://orcid.org/0000-0003-4882-1177)
- Ming‐Daw Tsai (ORCID: https://orcid.org/0000-0003-1374-0414)
- Wei-Ting Lin (ORCID: https://orcid.org/0009-0004-3149-205X)
- Kai-Fa Huang (ORCID: https://orcid.org/0000-0001-5235-7421)
- Wen‐Jin Wu (ORCID: https://orcid.org/0000-0002-7253-5384)
- Kai-Chun Yang (ORCID: https://orcid.org/0009-0006-9790-1244)
- Meng-Iao Fong
- Atsuo Kazuoka
- Eisho Tanida
Institutions
- Centre National de la Recherche Scientifique (FR)
- Universität Hamburg (DE)
- Philipps University of Marburg (DE)
- National Taiwan University (TW)
- University of Hyogo (JP)
- Tohoku University (JP)
- Kyoto University (JP)
- Commissariat à l'Énergie Atomique et aux Énergies Alternatives (FR)
- European Synchrotron Radiation Facility (FR)
- CEA Grenoble (FR)
- Nagoya Gakuin University (JP)
- Institute of Biological Chemistry, Academia Sinica (TW)
- SPring-8 (JP)
- Japan Synchrotron Radiation Research Institute (JP)
- Institut de Biologie Structurale (FR)
- Yokohama City University (JP)
- Université Grenoble Alpes (FR)
- The University of Osaka (JP)
Publication Details
- Journal
- Science Advances
- Published
- 2025-05-16
- DOI
- https://doi.org/10.1126/sciadv.adu7247
- Citations
- 4
- Primary Topic
- Light effects on plants
- Type
- article
- Field-Weighted Citation Impact
- 7.00
Funders
- Academia Sinica