Publication Abstract from PubMed
Cryptochromes are almost ubiquitous blue-light receptors and act in several species as central components of the circadian clock. Despite being evolutionary and structurally related with DNA photolyases, a class of light-driven DNA-repair enzymes, and having similar cofactor compositions, cryptochromes lack DNA-repair activity. Cryptochrome 3 from the plant Arabidopsis thaliana belongs to the DASH-type subfamily. Its crystal structure determined at 1.9 Angstroms resolution shows cryptochrome 3 in a dimeric state with the antenna cofactor 5,10-methenyltetrahydrofolate (MTHF) bound in a distance of 15.2 Angstroms to the U-shaped FAD chromophore. Spectroscopic studies on a mutant where a residue crucial for MTHF-binding, E149, was replaced by site-directed mutagenesis demonstrate that MTHF acts in cryptochrome 3 as a functional antenna for the photoreduction of FAD.
Cryptochrome 3 from Arabidopsis thaliana: structural and functional analysis of its complex with a folate light antenna.,Klar T, Pokorny R, Moldt J, Batschauer A, Essen LO J Mol Biol. 2007 Feb 23;366(3):954-64. Epub 2006 Dec 2. PMID:17188299[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
