title: Targeting Plant Ethylene Responses by Controlling Essential Protein-Protein Interactions in the Ethylene Pathway.
abstract: 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)-localized 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 corresponding peptide substantially reduces ethylene responses in planta. Our results uncover a novel mechanism 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.
authors.affiliation: Institute of Biochemical Plant Physiology, Heinrich-Heine University Düsseldorf, D-40204 Düsseldorf, Germany.
authors.forename: Melanie M A
authors.initials: MM
authors.lastname: Bisson
authors.affiliation: Institute of Biochemical Plant Physiology, Heinrich-Heine University Düsseldorf, D-40204 Düsseldorf, Germany. Electronic address: georg.groth@hhu.de.
authors.forename: Georg
authors.initials: G
authors.lastname: Groth
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000378:metabolism; D001681:Biological Assay; D005030:Ethylenes / Q000378:metabolism*; D005638:Fruit / Q000254:growth & development; D018551:Solanum lycopersicum / Q000254:growth & development; D008969:Molecular Sequence Data; D019913:Nuclear Localization Signals / Q000378:metabolism; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D011485:Protein Binding; D025941:Protein Interaction Mapping; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000378:metabolism; D015398:Signal Transduction; D013329:Structure-Activity Relationship
chemical_list: D029681:Arabidopsis Proteins; C119963:EIN2 protein, Arabidopsis; C494590:ETR1 protein, Arabidopsis; D005030:Ethylenes; D019913:Nuclear Localization Signals; D010455:Peptides; D011956:Receptors, Cell Surface; C036216:ethylene
keywords: ethylene responses; fruit ripening; inhibitor; peptide; protein-protein interactions