phosphoacceptor receiver (REC) domain of plant ethylene receptors ETR1, ETR2, and EIN4, and similar proteins
Plant ethylene receptors contain N-terminal transmembrane domains that contain an ethylene binding site and also serve in localization of the receptor to the endoplasmic reticulum or the Golgi apparatus and a C-terminal histidine kinase (HK)-like domain. There are five ethylene receptors (ETR1, ERS1, ETR2, ERS2, and EIN4) in Arabidopsis thaliana. ETR1, ETR2, and EIN4 also contain REC domains C-terminal to the HK domain. ETR1 and ERS1 belong to subfamily 1, and have functional HK domains while ETR2, ERS2, and EIN4 belong to subfamily 2, and lack the necessary residues for HK activity and may function as serine/threonine kinases. The plant hormone ethylene plays an important role in plant growth and development. It regulates seed germination, seedling growth, leaf and petal abscission, fruit ripening, organ senescence, and pathogen responses. REC domains function as phosphorylation-mediated switches within response regulators, but some also transfer phosphoryl groups in multistep phosphorelays.
Feature 1: metal binding site [ion binding site], 3 residue positions
Conserved feature residue pattern:[ED] [ED] [ED]
Evidence:
Comment:based on metal binding site of other family members
Comment:signal transduction in two-component systems is mediated by metal ion dependent phosphorelay reactions between protein histidine kinases and phosphoaccepting receiver domains in response regulator proteins
Comment:for many receivers, Mg2+ is the preferred metal ion, but other divalent ions such as Mn2+ are also used
Jiyao W et al.(2023). "The conserved domain database in 2023.",