Conformational dynamics are a key factor in signaling mediated by the receiver domain of a sensor histidine kinase from Arabidopsis thaliana

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14740%2F17%3A00095060" target="_blank" >RIV/00216224:14740/17:00095060 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.jbc.org/content/early/2017/08/31/jbc.M117.790212.short" target="_blank" >http://www.jbc.org/content/early/2017/08/31/jbc.M117.790212.short</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1074/jbc.M117.790212" target="_blank" >10.1074/jbc.M117.790212</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Conformational dynamics are a key factor in signaling mediated by the receiver domain of a sensor histidine kinase from Arabidopsis thaliana

Popis výsledku v původním jazyce

Multistep phosphorelay (MSP) cascades mediate responses to a wide spectrum of stimuli, including plant hormonal signaling, but several aspects of MSP await elucidation. Here, we provide first insight into the key step of MSP- mediated phosphotransfer in a eukaryotic system, the phosphorylation of the receiver domain of the histidine kinase CYTOKININ-INDEPENDENT 1 (CKI1(RD)) from Arabidopsis thaliana. We observed that the crystal structures of free, Mg2+-bound, and beryllofluoridated CKI1(RD) (a stable analogue of the labile phosphorylated form) were identical and similar to the active state of receiver domains of bacterial response regulators. However, the three CKI1(RD) variants exhibited different conformational dynamics in solution. NMR studies revealed that Mg2+ binding and beryllofluoridation alter the conformational equilibrium of the beta 3-beta 3 loop close to the phosphorylation site. Mutations that perturbed the conformational behavior of the beta 3-beta 3 loop while keeping the active- site aspartate intact resulted in suppression of CKI1 function. Mechanistically, homology modeling indicated that the beta 3 beta 3 loop directly interacts with the ATP- binding site of the CKI1 histidine kinase domain. The functional relevance of the conformational dynamics observed in the beta 3-beta 3 loop of CKI1(RD) was supported by a comparison with another A. thaliana histidine kinase, ETR1. In contrast to the highly dynamic beta 3- beta 3 loop of CKI1(RD), the corresponding loop of the ETR1 receiver domain (ETR1(RD)) exhibited little conformational exchange and adopted a different orientation in crystals. Biochem-ical data indicated that ETR1(RD) is involved in phosphorylation-independent signaling, implying a direct link between conformational behavior and the ability of eukaryotic receiver domains to participate in MSP.

Název v anglickém jazyce

Conformational dynamics are a key factor in signaling mediated by the receiver domain of a sensor histidine kinase from Arabidopsis thaliana

Popis výsledku anglicky

Multistep phosphorelay (MSP) cascades mediate responses to a wide spectrum of stimuli, including plant hormonal signaling, but several aspects of MSP await elucidation. Here, we provide first insight into the key step of MSP- mediated phosphotransfer in a eukaryotic system, the phosphorylation of the receiver domain of the histidine kinase CYTOKININ-INDEPENDENT 1 (CKI1(RD)) from Arabidopsis thaliana. We observed that the crystal structures of free, Mg2+-bound, and beryllofluoridated CKI1(RD) (a stable analogue of the labile phosphorylated form) were identical and similar to the active state of receiver domains of bacterial response regulators. However, the three CKI1(RD) variants exhibited different conformational dynamics in solution. NMR studies revealed that Mg2+ binding and beryllofluoridation alter the conformational equilibrium of the beta 3-beta 3 loop close to the phosphorylation site. Mutations that perturbed the conformational behavior of the beta 3-beta 3 loop while keeping the active- site aspartate intact resulted in suppression of CKI1 function. Mechanistically, homology modeling indicated that the beta 3 beta 3 loop directly interacts with the ATP- binding site of the CKI1 histidine kinase domain. The functional relevance of the conformational dynamics observed in the beta 3-beta 3 loop of CKI1(RD) was supported by a comparison with another A. thaliana histidine kinase, ETR1. In contrast to the highly dynamic beta 3- beta 3 loop of CKI1(RD), the corresponding loop of the ETR1 receiver domain (ETR1(RD)) exhibited little conformational exchange and adopted a different orientation in crystals. Biochem-ical data indicated that ETR1(RD) is involved in phosphorylation-independent signaling, implying a direct link between conformational behavior and the ability of eukaryotic receiver domains to participate in MSP.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10600 - Biological sciences

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Biological Chemistry

ISSN

0021-9258

e-ISSN

—

Svazek periodika

292

Číslo periodika v rámci svazku

42

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

16

Strana od-do

17525-17540

Kód UT WoS článku

000414009300032

EID výsledku v databázi Scopus

—