Conformational change induced by ATP binding correlates with enhanced biological function of Arabidopsis cryptochrome

Edited by Richard Cogdell

Received 27 January 2009; received in revised form 17 March 2009; accepted 18 March 2009. published online 25 March 2009.

Abstract

Cryptochromes are widely distributed blue light photoreceptors involved in numerous signaling functions in plants and animals. Both plant and animal-type cryptochromes are found to bind ATP and display intrinsic autokinase activity; however the functional significance of this activity remains a matter of speculation. Here we show in purified preparations of Arabidopsis cry1 that ATP binding induces conformational change independently of light and increases the amount and stability of light-induced flavin radical formation. Nucleotide binding may thereby provide a mechanism whereby light responsivity in organisms can be regulated through modulation of cryptochrome photoreceptor conformation.

Keywords: Cryptochrome, Photolyase, Blue light, Photoreceptor, ATP, Arabidopsis thaliana

a Université Paris 6, CNRS – UMR 7180, PCMP, F-75005 Paris, France

b Penn State University, Media, PA, USA

Corresponding author. Address: Université Paris 6, CNRS – UR5, PCMP, Casier 156, 4 Place Jussieu, 75005 Paris, France. Fax: + 33 144272916.

PII: S0014-5793(09)00229-4

doi:10.1016/j.febslet.2009.03.040

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