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Identification of a new cryptochrome class. Structure, function, and evolution.

Ronald Brudler·Kenichi Hitomi·Hiromi Daiyasu·Hiroyuki Toh·Ken-ichi Kucho·Masahiro Ishiura·Minoru Kanehisa·Victoria A Roberts·Takeshi Todo·John A Tainer·Elizabeth D Getzoff
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Abstract

Cryptochrome flavoproteins, which share sequence homology with light-dependent DNA repair photolyases, function as photoreceptors in plants and circadian clock components in animals. Here, we coupled sequencing of an Arabidopsis cryptochrome gene with phylogenetic, structural, and functional analyses to identify a new cryptochrome class (cryptochrome DASH) in bacteria and plants, suggesting that cryptochromes evolved before the divergence of eukaryotes and prokaryotes. The cryptochrome crystallographic structure, reported here for Synechocystis cryptochrome DASH, reveals commonalities with photolyases in DNA binding and redox-dependent function, despite distinct active-site and interaction surface features. Whole genome transcriptional profiling together with experimental confirmation of DNA binding indicated that Synechocystis cryptochrome DASH functions as a transcriptional repressor.

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Amino Acid SequenceAnimalsArabidopsisArabidopsis ProteinsBacterial ProteinsBinding SitesBiological ClocksCryptochromesCrystallography, X-RayCyanobacteriaDeoxyribodipyrimidine Photo-LyaseDrosophila ProteinsEvolution, MolecularEye ProteinsFlavoproteinsGenes, PlantHumansModels, MolecularMolecular Sequence DataOligonucleotide Array Sequence AnalysisPhotoreceptor Cells, InvertebratePhylogenyReceptors, G-Protein-CoupledSequence AlignmentSequence Analysis, DNASubstrate SpecificityJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Ronald Brudler, Kenichi Hitomi, Hiromi Daiyasu, Hiroyuki Toh, Ken-ichi Kucho, Masahiro Ishiura, Minoru Kanehisa, Victoria A Roberts, Takeshi Todo, John A Tainer, Elizabeth D Getzoff. 2003. Identification of a new cryptochrome class. Structure, function, and evolution.. https://doi.org/10.1016/s1097-2765(03)00008-x

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