RT Journal Article
SR Electronic
T1 Photoreceptor Regulation of CONSTANS Protein in Photoperiodic Flowering
JF Science
JO Science
FD American Association for the Advancement of Science
SP 1003
OP 1006
DO 10.1126/science.1091761
VO 303
IS 5660
A1 Valverde, Federico
A1 Mouradov, Aidyn
A1 Soppe, Wim
A1 Ravenscroft, Dean
A1 Samach, Alon
A1 Coupland, George
YR 2004
UL http://science.sciencemag.org/content/303/5660/1003.abstract
AB Many plants flower in response to seasonal fluctuations in day length. The CONSTANS (CO) gene of Arabidopsis promotes flowering in long days. Flowering is induced when CO messenger RNA expression coincides with the exposure of plants to light. However, how this promotes CO activity is unknown. We show that light stabilizes nuclear CO protein in the evening, whereas in the morning or in darkness the protein is degraded by the proteasome. Photoreceptors regulate CO stability and act antagonistically to generate daily rhythms in CO abundance. This layer of regulation refines the circadian rhythm in CO messenger RNA and is central to the mechanism by which day length controls flowering.