1.
Science
; 294(5544): 1108-11, 2001 Nov 02.
Article
in English
| MEDLINE
| ID: mdl-11691995
ABSTRACT
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.