Phytomelatonin receptor PMTR1-mediated signaling regulates stomatal closure in Arabidopsis thaliana.
J Pineal Res
; 65(2): e12500, 2018 Sep.
Article
em En
| MEDLINE
| ID: mdl-29702752
ABSTRACT
Melatonin has been detected in plants in 1995; however, the function and signaling pathway of this putative phytohormone are largely undetermined due to a lack of knowledge about its receptor. Here, we discovered the first phytomelatonin receptor (CAND2/PMTR1) in Arabidopsis thaliana and found that melatonin governs the receptor-dependent stomatal closure. The application of melatonin induced stomatal closure through the heterotrimeric G protein α subunit-regulated H2 O2 and Ca2+ signals. The Arabidopsis mutant lines lacking AtCand2 that encodes a candidate G protein-coupled receptor were insensitive to melatonin-induced stomatal closure. Accordingly, the melatonin-induced H2 O2 production and Ca2+ influx were completely abolished in cand2. CAND2 is a membrane protein that interacts with GPA1 and the expression of AtCand2 was tightly regulated by melatonin in various organs and guard cells. CAND2 showed saturable and specific 125 I-melatonin binding, with apparent Kd (dissociation constant) of 0.73 ± 0.10 nmol/L (r2 = .99), demonstrating this protein is a phytomelatonin receptor (PMTR1). Our results suggest that the phytomelatonin regulation of stomatal closure is dependent on its receptor CAND2/PMTR1-mediated H2 O2 and Ca2+ signaling transduction cascade.
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Base de dados:
MEDLINE
Assunto principal:
Arabidopsis
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Sinalização do Cálcio
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Proteínas de Arabidopsis
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Receptores Acoplados a Proteínas G
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Estômatos de Plantas
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Melatonina
Idioma:
En
Revista:
J Pineal Res
Assunto da revista:
ENDOCRINOLOGIA
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
China