Blue-light dependent reactive oxygen species formation by Arabidopsis cryptochrome may define a novel evolutionarily conserved signaling mechanism.
Cryptochromes are widespread blue-light absorbing flavoproteins with important signaling roles. In plants they mediate de-etiolation, developmental and stress responses resulting from interaction with downstream signaling partners such as transcription factors and components of the proteasome. Recently, it has been shown that Arabidopsis cry1 activation by blue light also results in direct enzymatic conversion of molecular oxygen (O2 ) to reactive oxygen species (ROS) and hydrogen peroxide (H2 O2 ) in vitro. Here we explored whether direct enzymatic synthesis of ROS by Arabidopsis cry1 can play a physiological role in vivo. ROS formation resulting from cry1 expression was measured by fluorescence assay in insect cell cultures and in Arabidopsis protoplasts from cryptochrome mutant seedlings. Cell death was determined by colorimetric assay. We found that ROS formation results from cry1 activation and induces cell death in insect cell cultures. In plant protoplasts, cryptochrome activation results in rapid increase in ROS formation and cell death. We conclude that ROS formation by cryptochromes may indeed be of physiological relevance and could represent a novel paradigm for cryptochrome signaling.
UMR 8256 (B2A) CNRS - UPMC, IBPS, Université Pierre et Marie Curie, Bat C 3éme étage, 9 quai Saint-Bernard, 75252, Paris Cedex 05, France.
Laurent
L
Consentino
UMR 8256 (B2A) CNRS - UPMC, IBPS, Université Pierre et Marie Curie, Bat C 3éme étage, 9 quai Saint-Bernard, 75252, Paris Cedex 05, France.
Stefan
S
Lambert
UMR 8256 (B2A) CNRS - UPMC, IBPS, Université Pierre et Marie Curie, Bat C 3éme étage, 9 quai Saint-Bernard, 75252, Paris Cedex 05, France.|Department of Biomedical Engineering, Florida Institute of Technology, 150 W. University Blvd, Melbourne, FL, 32901, USA.
Carlos
C
Martino
UMR 8256 (B2A) CNRS - UPMC, IBPS, Université Pierre et Marie Curie, Bat C 3éme étage, 9 quai Saint-Bernard, 75252, Paris Cedex 05, France.
Nathalie
N
Jourdan
UMR 8256 (B2A) CNRS - UPMC, IBPS, Université Pierre et Marie Curie, Bat C 3éme étage, 9 quai Saint-Bernard, 75252, Paris Cedex 05, France.
Pierre-Etienne
PE
Bouchet
UMR 8256 (B2A) CNRS - UPMC, IBPS, Université Pierre et Marie Curie, Bat C 3éme étage, 9 quai Saint-Bernard, 75252, Paris Cedex 05, France.
Jacques
J
Witczak
UMR 8256 (B2A) CNRS - UPMC, IBPS, Université Pierre et Marie Curie, Bat C 3éme étage, 9 quai Saint-Bernard, 75252, Paris Cedex 05, France.|Facultad de Ciencias Exactas y Naturales, Universidad de Belgrano (UB), Villanueva 1324, Buenos Aires, C1426BMJ, Argentina.
Pablo
P
Castello
UMR 8256 (B2A) CNRS - UPMC, IBPS, Université Pierre et Marie Curie, Bat C 3éme étage, 9 quai Saint-Bernard, 75252, Paris Cedex 05, France.|Botany Department, Faculty of Science, Tanta University, 31527, Tanta, Egypt.
Mohamed
M
El-Esawi
UMR7622 CNRS-UPMC Biologie du Développement, IBPS, Bat C 2ème étage, boîte 24, 4 place Jussieu, 75005, Paris Cedex 05, France.
Francoise
F
Corbineau
UMR 8256 (B2A) CNRS - UPMC, IBPS, Université Pierre et Marie Curie, Bat C 3éme étage, 9 quai Saint-Bernard, 75252, Paris Cedex 05, France.
Alain
A
d'Harlingue
UMR 8256 (B2A) CNRS - UPMC, IBPS, Université Pierre et Marie Curie, Bat C 3éme étage, 9 quai Saint-Bernard, 75252, Paris Cedex 05, France.|Xavier University, 3800 Victory Parkway, Cincinatti, OH, 45207, USA.
Margaret
M
Ahmad
D017360:Arabidopsis / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D005075:Biological Evolution; D016923:Cell Death / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D056931:Cryptochromes / Q000378:metabolism*; D008027:Light; D010100:Oxygen / Q000494:pharmacology; D011523:Protoplasts / Q000187:drug effects / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D011995:Recombination, Genetic / Q000235:genetics; D061987:Sf9 Cells; D015398:Signal Transduction / Q000187:drug effects / Q000528:radiation effects*; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism
D029681:Arabidopsis Proteins; C538962:CRY1 protein, Arabidopsis; D056931:Cryptochromes; D017382:Reactive Oxygen Species; D010100:Oxygen
Arabidopsis thaliana; cryptochrome; oxidative stress; photomorphogenesis; photoreceptor; reactive oxygen species (ROS) signaling