Interaction of the response regulator ARR4 with phytochrome B in modulating red light signaling.
The Arabidopsis thaliana response regulator 4, expressed in response to phytochrome B action, specifically interacts with the extreme amino-terminus of the photoreceptor. The response regulator 4 stabilizes the active Pfr form of phytochrome B in yeast and in planta, thus elevates the level of the active photoreceptor in vivo. Accordingly, transgenic Arabidopsis plants overexpressing the response regulator 4 display hypersensitivity to red light but not to light of other wavelengths. We propose that the response regulator 4 acts as an output element of a two-component system that modulates red light signaling on the level of the phytochrome B photoreceptor.
Sweere
U
U
Institut für Biologie II / Botanik, Universität Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany.
Eichenberg
K
K
Lohrmann
J
J
Mira-Rodado
V
V
Bäurle
I
I
Kudla
J
J
Nagy
F
F
Schafer
E
E
Harter
K
K
D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism* / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D003624:Darkness; D017343:Genes, Plant; D008027:Light; D010641:Phenotype; D010766:Phosphorylation; D010786:Photoreceptor Cells; D010834:Phytochrome / Q000737:chemistry / Q000378:metabolism*; D051939:Phytochrome B; D030821:Plants, Genetically Modified; D011487:Protein Conformation; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015398:Signal Transduction; D014157:Transcription Factors; D020798:Two-Hybrid System Techniques; D015003:Yeasts / Q000235:genetics / Q000378:metabolism
C113359:ARR4 protein, Arabidopsis; D029681:Arabidopsis Proteins; C497952:PHYB protein, Arabidopsis; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D010834:Phytochrome; D051939:Phytochrome B