Structure of a flavin-binding plant photoreceptor domain: insights into light-mediated signal transduction.

ABSTRACT: Phototropin, a major blue-light receptor for phototropism in seed plants, exhibits blue-light-dependent autophosphorylation and contains two light, oxygen, or voltage (LOV) domains and a serine/threonine kinase domain. The LOV domains share homology with the PER-ARNT-SIM (PAS) superfamily, a diverse group of sensor proteins. Each LOV domain noncovalently binds a single FMN molecule and exhibits reversible photochemistry in vitro when expressed separately or in tandem. We have determined the crystal structure of the LOV2 domain from the phototropin segment of the chimeric fern photoreceptor phy3 to 2.7-A resolution. The structure constitutes an FMN-binding fold that reveals how the flavin cofactor is embedded in the protein. The single LOV2 cysteine residue is located 4.2 A from flavin atom

SUBMITTER: Crosson S 

PROVIDER: S-EPMC30595 | biostudies-literature | 2001 Mar

REPOSITORIES: biostudies-literature