Journal Article

Jasmonate perception by inositol-phosphate-potentiated COI1–JAZ co-receptor

Zheng, Ning, Sharon, Michal, Tan, Xu, Howe, Gregg A., Browse, John, He, Sheng Yang, Rizo, Josep, Mao, Haibin, Hinds, Thomas R., Sheard, Laura B., Withers, John, Hsu, Fong-Fu, Kobayashi, Yuichi, Ben-Nissan, Gili

2010

Overview

Jasmonates are a family of plant hormones that regulate plant growth, development and responses to stress. The F-box protein CORONATINE INSENSITIVE 1 (COI1) mediates jasmonate signalling by promoting hormone-dependent ubiquitylation and degradation of transcriptional repressor JAZ proteins. Despite its importance, the mechanism of jasmonate perception remains unclear. Here we present structural and pharmacological data to show that the true Arabidopsis jasmonate receptor is a complex of both COI1 and JAZ. COI1 contains an open pocket that recognizes the bioactive hormone (3 R ,7 S )-jasmonoyl- l -isoleucine (JA-Ile) with high specificity. High-affinity hormone binding requires a bipartite JAZ degron sequence consisting of a conserved α-helix for COI1 docking and a loop region to trap the hormone in its binding pocket. In addition, we identify a third critical component of the jasmonate co-receptor complex, inositol pentakisphosphate, which interacts with both COI1 and JAZ adjacent to the ligand. Our results unravel the mechanism of jasmonate perception and highlight the ability of F-box proteins to evolve as multi-component signalling hubs. Three-part receptor for jasmonate plant hormones The receptors for several important plant hormones have been identified in recent years, including those for auxin, the gibberellins and abscisic acid, and structure–function studies have revealed their mechanisms of action. Now the mechanism by which plant cells recognize the jasmonate phytohormones — key players in growth regulation, development and defence responses — is reported. The jasmonate receptor is a three-molecule complex consisting of the F-box protein COI1, a JAZ (JASMONATE ZIM DOMAIN) transcriptional repressor, and inositol pentakisphosphate. All three receptor components are required for high-affinity hormone binding. This system for jasmonate perception involves mechanisms that are distinct from those of the other plant hormones studied so far, although all depend on hormone-mediated protein interactions. The F-box protein CORONATINE INSENSITIVE 1 (COI1) mediates jasmonate signalling by promoting hormone-dependent ubiquitylation and degradation of the JASMONATE ZIM DOMAIN (JAZ) family of transcriptional repressors. These authors elucidate the mechanism of jasmonate perception. They present structural and pharmacological data to show that the true jasmonate receptor is a complex of both COI1 and JAZ. In addition, inositol pentakisphosphate functions as a critical component of the hormone receptor complex.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 631/449/1741 / 631/45/535 / 631/80/86/2363 / Amino Acid Sequence / Amino Acids - chemistry / Amino Acids - metabolism / Arabidopsis - chemistry / Arabidopsis - metabolism / Arabidopsis Proteins - chemistry / Arabidopsis Proteins - metabolism / Binding Sites / Biological and medical sciences / Crystal structure / Crystallography, X-Ray / Cyclopentanes - chemistry / Cyclopentanes - metabolism / Data collection / F-Box Proteins - chemistry / F-Box Proteins - metabolism / Fundamental and applied biological sciences. Psychology / Growth (Plants) / Growth regulators / Hormones / Humanities and Social Sciences / Indenes - chemistry / Indenes - metabolism / Inositol / Inositol Phosphates - metabolism / Isoleucine - analogs & derivatives / Isoleucine - chemistry / Isoleucine - metabolism / Jasmonates / Mass spectrometry / Metabolism / Models, Molecular / Molecular Sequence Data / multidisciplinary / Oxylipins - chemistry / Oxylipins - metabolism / Peptide Fragments - chemistry / Peptide Fragments - metabolism / Perception / Phosphates / Plant growth / Plant Growth Regulators - chemistry / Plant Growth Regulators - metabolism / Plant physiology and development / Protein Binding / Protein Structure, Tertiary / Proteins / Repressor Proteins - chemistry / Repressor Proteins - metabolism / Science / Science (multidisciplinary) / Signal Transduction / Studies / Ubiquitin