title: Comparative functional analysis of full-length and N-terminal fragments of phytochrome C, D and E in red light-induced signaling.
abstract: Phytochromes (phy) C, D and E are involved in the regulation of red/far-red light-induced photomorphogenesis of Arabidopsis thaliana, but only limited data are available on the mode of action and biological function of these lesser studied phytochrome species. We fused N-terminal fragments or full-length PHYC, D and E to YELLOW FLUORESCENT PROTEIN (YFP), and analyzed the function, stability and intracellular distribution of these fusion proteins in planta. The activity of the constitutively nuclear-localized homodimers of N-terminal fragments was comparable with that of full-length PHYC, D, E-YFP, and resulted in the regulation of various red light-induced photomorphogenic responses in the studied genetic backgrounds. PHYE-YFP was active in the absence of phyB and phyD, and PHYE-YFP controlled responses, as well as accumulation, of the fusion protein in the nuclei, was saturated at low fluence rates of red light and did not require functional FAR-RED ELONGATED HYPOCOTYL1 (FHY-1) and FHY-1-like proteins. Our data suggest that PHYC-YFP, PHYD-YFP and PHYE-YFP fusion proteins, as well as their truncated N-terminal derivatives, are biologically active in the modulation of red light-regulated photomorphogenesis. We propose that PHYE-YFP can function as a homodimer and that low-fluence red light-induced translocation of phyE and phyA into the nuclei is mediated by different molecular mechanisms.
authors.affiliation: Institute of Plant Biology, Biological Research Centre, Temesvári krt.62., H-6726, Szeged, Hungary.
authors.forename: Éva
authors.initials: É
authors.lastname: Ádám
authors.affiliation: Institute of Botany, University of Freiburg, Schänzlestrasse 1, D-79104, Freiburg, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Kircher
authors.affiliation: Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, 59717, USA.
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.affiliation: Institute of Botany, University of Freiburg, Schänzlestrasse 1, D-79104, Freiburg, Germany.
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Mérai
authors.affiliation: Departament de Genètica Molecular, Center for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus Univ. Autònoma de Barcelona, Bellaterra, 08193, Barcelona, Spain.
authors.forename: Nahuel
authors.initials: N
authors.lastname: González-Schain
authors.affiliation: BIOSS Center for Biological Signalling Studies, University of Freiburg, Schänzlestrasse 18, D-79104, Freiburg, Germany.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Hörner
authors.affiliation: Institute of Plant Biology, Biological Research Centre, Temesvári krt.62., H-6726, Szeged, Hungary.
authors.forename: András
authors.initials: A
authors.lastname: Viczián
authors.affiliation: Departament de Genètica Molecular, Center for Research in Agricultural Genomics (CRAG) CSIC-IRTA-UAB-UB, Campus Univ. Autònoma de Barcelona, Bellaterra, 08193, Barcelona, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Monte
authors.affiliation: Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, 59717, USA.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Sharrock
authors.affiliation: Institute of Botany, University of Freiburg, Schänzlestrasse 1, D-79104, Freiburg, Germany.|BIOSS Center for Biological Signalling Studies, University of Freiburg, Schänzlestrasse 18, D-79104, Freiburg, Germany.
authors.forename: Eberhard
authors.initials: E
authors.lastname: Schäfer
authors.affiliation: Institute of Plant Biology, Biological Research Centre, Temesvári krt.62., H-6726, Szeged, Hungary.|Institute of Molecular Plant Science, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3JH, UK.
authors.forename: Ferenc
authors.initials: F
authors.lastname: Nagy
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001692:Biological Transport; D002467:Cell Nucleus; D019281:Dimerization; D008027:Light; D009024:Morphogenesis; D010834:Phytochrome / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; D010834:Phytochrome
keywords: nuclear body formation; nuclear translocation; photomorphogenesis; photoreceptor; phytochrome E