Arabidopsis FHY1 and FHY1-LIKE Are Not Required for Phytochrome A Signal Transduction in the Nucleus  

作　　者：Chiara Menon Cornelia Klose Andreas Hiltbrunner 

机构地区：[1]Center for Plant Molecular Biology,University of Tubingen,72076 Tubingen,Germany [2]Faculty of Biology,Institute of Biology II,University of Freiburg,79104 Freiburg,Germany [3]Signalling Research Centres BIOSS and CIBSS,University of Freiburg,79104 Freiburg,Germany

出　　处：《Plant Communications》2020年第2期34-44,共11页植物通讯（英文）

基　　金：This study was supported by the German Research Foundation(DFG)under Germany’s Excellence Strategy(BIOSS-EXC-294,CIBSS-EXC-2189-Project ID 390939984);by grants from the DFG(DFG HI 1369/4-1 and HI 1369/5-1);the Human Frontier Science Program Organization(HFSP research grant RGP0025/2013)to A.H.C.K.;was supported by the Ministry of Science,Research and the Arts Baden-Wuerttemberg;The article processing charge was funded by the German Research Foundation(DFG)and the Albert Ludwigs University Freiburg in the funding programme Open Access Publishing.

摘　　要：Photoreceptors of the phytochrome family control a multitude of responses in plants.Phytochrome A(phyA)is essential for far-red light perception,which is important for germination and seedling establishment in strong canopy shade.Translocation of phyA from the cytosol into nucleus is a key step in farred light signaling and requires FAR-RED ELONGATED HYPOCOTYL 1(FHY1)and FHY1-LIKE(FHL).FHY1/FHL bind to phyA downstream signaling components.Therefore,it has been suggested that FHY1/FHL also have a function in assembling phyA transcription factor complexes in the nucleus.Yet,in this study,we show that constitutively nuclear-localized phyA is active in the absence of FHY1 and FHL.Furthermore,an artificial FHY1,consisting of an SV40 NLS,a phyA binding site,and a YFP tag as spacer between them,complements the fhy1-3 fhl-1 double mutant.These findings show that FHY1 and FHL are not required for phyA downstream signaling in the nucleus.However,we found that lines expressing phyA-NLS-YFP are hypersensitive to red and far-red light and that slightly increased levels of constitutively nuclear-localized phyA result in photomorphogenic development in the dark.Thus,restricting phyA to the cytosol and inducing nuclear transport in light by interaction with FHY1/FHL might be important to suppress photomorphogenesis in the dark.

关 键 词：PHYTOCHROME PHYA FHY1 FHL nuclear transport far-red light 

分 类 号：Q78[生物学—分子生物学]