title: Blue-light dependent ROS formation by Arabidopsis cryptochrome-2 may contribute toward its signaling role.
abstract: Cryptochromes are blue-light absorbing flavoproteins with many important signaling roles in plants, including in de-etiolation, development, and stress response. They interact with downstream signaling partners such as transcription factors and components of the proteasome, and thereby alter regulation of nuclear gene expression in a light dependent manner. In a prior study, it has also been shown that Arabidopsis cry1 activation by blue light results in direct enzymatic conversion of molecular oxygen (O2) to ROS (reactive oxygen species) in vivo leading to cell death in overexpressing lines. Here we extend these observations to show that Atcry2 is translocated from the cytosol to the nucleus in response to blue light illumination, resulting in nuclear accumulation of ROS in expressing insect cell cultures. These observations suggest that ROS formation may represent a novel means of signaling by Atcry2 distinct from, and perhaps complementary to, the currently known mechanism of light-mediated conformational change.
authors.affiliation: a UMR 8256 (B2A) CNRS - UPMC; IBPS; Université Pierre et Marie Curie 9 ; Paris , France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Jourdan
authors.forename: Carlos F
authors.initials: CF
authors.lastname: Martino
authors.forename: Mohamed
authors.initials: M
authors.lastname: El-Esawi
authors.forename: Jacques
authors.initials: J
authors.lastname: Witczak
authors.forename: Pierre-Etienne
authors.initials: PE
authors.lastname: Bouchet
authors.forename: Alain
authors.initials: A
authors.lastname: d'Harlingue
authors.forename: Margaret
authors.initials: M
authors.lastname: Ahmad
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001692:Biological Transport; D016923:Cell Death; D002467:Cell Nucleus / Q000378:metabolism*; D056931:Cryptochromes / Q000235:genetics / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D007313:Insecta; D008027:Light; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; C538962:CRY1 protein, Arabidopsis; D056931:Cryptochromes; D017382:Reactive Oxygen Species
keywords: ROS; cryptochrome; light signaling; nuclear localization; oxidative stress; photoreceptor