幾種重要植物激素的受體最近幾年已被發(fā)現(xiàn),，包括植物生長素（茁長素）,、赤霉素和脫落酸的受體,，而且結(jié)構(gòu)-功能研究也顯示了它們的作用機(jī)制。現(xiàn)在,，植物細(xì)胞識別“茉莉素植物激素”（生長調(diào)控,、發(fā)育和防衛(wèi)響應(yīng)中的關(guān)鍵成分）也已被發(fā)現(xiàn)。
茉莉素受體是一個(gè)三分子復(fù)合物,，由F-box 蛋白 COI1,、一個(gè)JAZ (JASMONATE ZIM-domain)轉(zhuǎn)錄抑制因子和“肌醇戊基磷酸鹽”(inositol pentakisphosphate)組成。所有三個(gè)成分都是高親和性激素結(jié)合所必需的,。用于茉莉素識別的這個(gè)體系涉及與迄今所研究的其他植物激素的機(jī)制截然不同的機(jī)制,，盡管它們都取決于由激素調(diào)控的蛋白相互作用。（生物谷Bioon.com）
生物谷推薦英文摘要：
Nature doi:10.1038/nature09430
Jasmonate perception by inositol-phosphate-potentiated COI1–JAZ co-receptor
Laura B. Sheard,Xu Tan,Haibin Mao,John Withers,Gili Ben-Nissan,Thomas R. Hinds,Yuichi Kobayashi,Fong-Fu Hsu,Michal Sharon,John Browse,Sheng Yang He,Josep Rizo,Gregg A. Howe& Ning Zheng
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 (3R,7S)-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.
