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1jnu
From Proteopedia
Photoexcited structure of the plant photoreceptor domain, phy3 LOV2
Overview
The phototropins are flavoprotein kinases that control phototropic bending, light-induced chloroplast movement, and stomatal opening in plants. Two flavin mononucleotide binding light, oxygen, or voltage (LOV) domains are the sites for initial photochemistry in these blue light photoreceptors. We have determined the steady state, photoexcited crystal structure of a flavin-bound LOV domain. The structure reveals a unique photochemical switch in the flavin binding pocket in which the absorption of light drives the formation of a reversible covalent bond between a highly conserved Cys residue and the flavin cofactor. This provides a molecular picture of a cysteinyl-flavin covalent adduct, the presumed signaling species that leads to phototropin kinase activation and subsequent signal transduction. We identify closely related LOV domains in two eubacterial proteins that suggests the light-induced conformational change evident in this structure is an ancient biomolecular response to light, arising before the appearance of plants.
About this Structure
1JNU is a Single protein structure of sequence from Eukaryota. Full crystallographic information is available from OCA.
Reference
Photoexcited structure of a plant photoreceptor domain reveals a light-driven molecular switch., Crosson S, Moffat K, Plant Cell. 2002 May;14(5):1067-75. PMID:12034897 Page seeded by OCA on Fri May 2 21:28:24 2008
