Arabidopsis CPR5 regulatesmolecular association withethylene signaling viathe ETR1 receptor

• Published in: 植物学报：英文版 Vol. 59; no. 11; pp. 810 - 824
• Main Author: Feifei Wang;Lijuan Wang;Longfei Qiao;Jiacai Chen;Maria Belen Pappa;Haixia Pei;Tao Zhang;Caren Chang;Chun-Hai Dong
• Format: Journal Article
• Language: English
• Published: 2017
• ISSN: 1672-9072; 1744-7909

The plant hormone ethylene plays variousfunctions in plant growth, development and response toenvironmental stress. Ethylene is perceived by membrane-bound ethylene receptors, and among the homologousreceptors in Arabidopsis, the ETRI ethylene receptor playsa major role. The present study provides evidencedemonstrating that Arabidopsis CPR5 functions as a novelETRI receptor-interacting protein in regulating ethyleneresponse and signaling. Yeast split ubiquitin assays and bi-fluorescence complementation studies in plant cellsindicated that CPR5 directly interacts with the ETRIreceptor. Genetic analyses indicated that mutant allelesof cpr5 can suppress ethylene insensitivity in both etr1-1 andetrl-2, but not in other dominant ethylene receptormutants. Overexpression of Arabidopsis CPR5 either intransgenic Arabidopsis plants, or ectopically in tobacco,significantly enhanced ethylene sensitivity. These findingsindicate that CPR5 plays a critical role in regulatingethylene signaling. CPR5 is localized to endomembranestructures and the nucleus, and is involved in variousregulatory pathways, including pathogenesis, leaf senes-cence, and spontaneous cell death. This study providesevidence for a novel regulatory function played by CPR5 inthe ethylene receptor signaling pathway in Arabidopsis.