A marine cryptochrome with an inverse photo-oligomerization mechanism

Vu, H. H.; Behrmann, H.; Hanic, M.; Jeyasankar, G.; Krishnan, S.; Dannecker, D.; Hammer, C.; Gunkel, M.; Solovyov, I. A.; Wolf, E.; Behrmann, E.

doi:10.1101/2023.06.02.543409

bioRxiv · 10.1101/2023.06.02.543409

A marine cryptochrome with an inverse photo-oligomerization mechanism

Vu, H. H.·Behrmann, H.·Hanic, M.·Jeyasankar, G.·Krishnan, S.·Dannecker, D.·Hammer, C.·Gunkel, M.·Solovyov, I. A.·Wolf, E.·Behrmann, E.

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Abstract

Cryptochromes (CRYs) are a structurally conserved but functionally diverse family of proteins that can confer unique sensory properties to organisms. In the marine bristle worm Platynereis dumerilii, its light receptive cryptochrome L-CRY (PdLCry) allows the animal to discriminate between sunlight and moonlight, an important requirement for synchronizing its lunar cycle-dependent mass spawning. Using cryo-electron microscopy, we show that in the dark, PdLCry adopts a dimer arrangement observed neither in plant nor insect CRYs. Intense illumination disassembles the dimer into monomers. Structural and functional data suggest a mechanistic coupling between the light-sensing flavin adenine dinucleotide chromophore, the dimer interface, and the C-terminal tail helix, with a likely involvement of the phosphate binding loop. Taken together, our work establishes PdLCry as a CRY protein with inverse photo-oligomerization with respect to plant CRYs, and provides molecular insights into how this protein might help discriminating the different light intensities associated with sunlight and moonlight.

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Vu, H. H., Behrmann, H., Hanic, M., Jeyasankar, G., Krishnan, S., Dannecker, D., Hammer, C., Gunkel, M., Solovyov, I. A., Wolf, E., Behrmann, E.. 2023-06-02. A marine cryptochrome with an inverse photo-oligomerization mechanism. https://doi.org/10.1101/2023.06.02.543409

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