D 2002

A His-to-Asp phosphorelay modifies the activity of ARR4 on phytochrome signaling.

MIRA-RODADO, Virtudes, Uta SWEERE, Matej LEXA, Jakub HORÁK, Erzsebet FEJES et. al.

Basic information

Original name

A His-to-Asp phosphorelay modifies the activity of ARR4 on phytochrome signaling.

Authors

MIRA-RODADO, Virtudes (724 Spain), Uta SWEERE (276 Germany), Matej LEXA (703 Slovakia), Jakub HORÁK (203 Czech Republic, guarantor), Erzsebet FEJES (348 Hungary), Ferenc NAGY (348 Hungary), Eberhard SCHÄFER (276 Germany) and Klaus HARTER (276 Germany)

Edition

Sevilla, Spain, XIII International Conference on Arabidopsis Research, p. 421-421, 2002

Publisher

CSIC, Madrid

Other information

Language

English

Type of outcome

Stať ve sborníku

Field of Study

Genetics and molecular biology

Country of publisher

Spain

Confidentiality degree

není předmětem státního či obchodního tajemství

RIV identification code

RIV/00216224:14310/02:00006184

Organization unit

Faculty of Science

Keywords in English

phytochrome signaling; two-component system; response regulator; photomorphogenesis; Arabidopsis thaliana
Změněno: 14/5/2003 15:22, Mgr. Jakub Horák, Dr. rer. nat.

Abstract

V originále

The Arabidopsis thaliana response regulator 4 (ARR4), expressed in response to phytochrome B (phyB) action, specifically interacts with the extreme N-terminus of the photoreceptor. ARR4 stabilizes the active Pfr form of phyB in yeast and in planta, thus elevates the level of the active photoreceptor in vivo. Accordingly, transgenic Arabidopsis plants overexpressing ARR4 display hypersensitivity to red light but not to light of other wavelengths. We therefore propose that ARR4 acts as an output element of a two-component system that modulates red light signaling on the level of the phyB photoreceptor. The two-component system is a signal transduction mechanism that requires a His-to-Asp phosphorelay to modulate the activity of a response regulator (e.g. ARR4). Consequently, we generated transgenic Arabidopsis lines expressing a non-phosphorylable form of ARR4 (ARR4D95N). These lines show hyposensitivity to light observed also for an ARR4 loss-of-function mutant. These results suggest that the action of ARR4 on phyB requires a His-to-Asp phosphorelay. By yeast two-hybrid approach and co-immunoprecipitation assays we identified the histidine phosphotransfer protein 1 (AHP1) to specifically interact with ARR4. Thus, AHP1 may mediate a phosphotransfer from different sensor histidine kinases to ARR4. Because the activities of multiple sensor histidine kinases are integrated at the level of AHPs, ARR4 may be a target of a complex two-component signaling network, which in turn regulates phy-dependent signal transduction. To understand, how this network functions, it is essential to identify the stimuli, and therefore, the sensor histidine kinases that initiate the AHP1-to-ARR4 phosphotransfer process.

Links

GA204/99/D024, research and development project
Name: Funkce homologů bakteriálních regulátorů indukovatelných dusičnany v rostlinách Arabidopsis thaliana
Investor: Czech Science Foundation, The role of nitrate-inducible bacterial response regulator homologs in Arabidopsis thaliana