Arabidopsis cryptochrome 2 (CRY2) functions by the photoactivation mechanism distinct from the tryptophan (trp) triad-dependent photoreduction.

ABSTRACT: Cryptochromes are blue-light receptors mediating various light responses in plants and animals. The photochemical mechanism of cryptochromes is not well understood. It has been proposed that photoactivation of cryptochromes involves the blue-light-dependent photoreduction of flavin adenine dinucleotide via the electron transport chain composed of three evolutionarily conserved tryptophan residues known as the "trp triad." We investigated this hypothesis by analyzing the photochemical and physiological activities of Arabidopsis cryptochrome 2 (CRY2) mutations altered in each of the three trp-triad residues. We found that all trp-triad mutations of CRY2 tested lost photoreduction activity in vitro but retained the physiological and biochemical activities in vivo. Some of the trp-triad mutati

SUBMITTER: Li X 

PROVIDER: S-EPMC3251054 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature