Targeting Plant Ethylene Responses by Controlling Essential Protein-Protein Interactions in the Ethylene Pathway  

作　　者：Melanie M.A. Bisson Georg Groth 

机构地区：[1]Institute of Biochemical Plant Physiology, Heinrich-Heine University Dusseldorf, D-40204 Dusseldorf, Germany

出　　处：《Molecular Plant》2015年第8期1165-1174,共10页分子植物（英文版）

摘　　要：The gaseous plant hormone ethylene regulates many processes of high agronomic relevance throughout the life span of plants. A central element in ethylene signaling is the endoplasmic reticulum （ER）-Iocalized membrane protein ETHYLENE INSENSITIVE2 （EIN2）. Recent studies indicate that in response to ethylene, the extra-membranous C-terminal end of EIN2 is proteolytically processed and translocated from the ER to the nucleus. Here, we report that the conserved nuclear localization signal （NLS） mediating nuclear import of the EIN2 C-terminus provides an important domain for complex formation with ethylene receptor ETHYLENE RESPONSE1 （ETR1）. EIN2 lacking the NLS domain shows strongly reduced affinity for the receptor. Interaction of EIN2 and ETR1 is also blocked by a synthetic peptide of the NLS motif. The corre- sponding peptide substantially reduces ethylene responses in planta. Our results uncover a novel mecha- nism and type of inhibitor interfering with ethylene signal transduction and ethylene responses in plants. Disruption of essential protein-protein interactions in the ethylene signaling pathway as shown in our study for the EIN2-ETR1 complex has the potential to guide the development of innovative ethylene antagonists for modern agriculture and horticulture.The gaseous plant hormone ethylene regulates many processes of high agronomic relevance throughout the life span of plants. A central element in ethylene signaling is the endoplasmic reticulum （ER）-Iocalized membrane protein ETHYLENE INSENSITIVE2 （EIN2）. Recent studies indicate that in response to ethylene, the extra-membranous C-terminal end of EIN2 is proteolytically processed and translocated from the ER to the nucleus. Here, we report that the conserved nuclear localization signal （NLS） mediating nuclear import of the EIN2 C-terminus provides an important domain for complex formation with ethylene receptor ETHYLENE RESPONSE1 （ETR1）. EIN2 lacking the NLS domain shows strongly reduced affinity for the receptor. Interaction of EIN2 and ETR1 is also blocked by a synthetic peptide of the NLS motif. The corre- sponding peptide substantially reduces ethylene responses in planta. Our results uncover a novel mecha- nism and type of inhibitor interfering with ethylene signal transduction and ethylene responses in plants. Disruption of essential protein-protein interactions in the ethylene signaling pathway as shown in our study for the EIN2-ETR1 complex has the potential to guide the development of innovative ethylene antagonists for modern agriculture and horticulture.

关 键 词：fruit ripening ethylene responses PEPTIDE protein-protein interactions INHIBITOR 

分 类 号：Q51[生物学—生物化学] TQ221.211[化学工程—有机化工]