植物学报 ›› 2006, Vol. 23 ›› Issue (5): 531-542.

所属专题: 激素香山会议专辑 (2006年23卷5期)

• 综述*乙烯 • 上一篇    下一篇

乙烯信号转导的分子机制

安丰英 郭红卫   

  1. (北京大学生命科学学院植物基因工程和蛋白质工程国家重点实验室, 北京 100871)
  • 收稿日期:2006-08-01 修回日期:2006-09-01 出版日期:2006-09-25 发布日期:2006-09-25
  • 通讯作者: 郭红卫

Molecular Mechanism of Ethylene Signal Transduction

Fengying An, Hongwei Guo   

  1. (The National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, China)
  • Received:2006-08-01 Revised:2006-09-01 Online:2006-09-25 Published:2006-09-25
  • Contact: Hongwei Guo

摘要: 气态植物激素乙烯在植物生长发育和应对生物及非生物胁迫过程中起着重要作用。在过去的十几年中, 对模式植物拟南芥的分子遗传研究已建立从信号感知到转录调控的乙烯信号转导线性模型。拟南芥共有5个乙烯受体ETR1、ERS1、ETR2、ERS2和EIN4, 目前已知ETR1定位在内质网上, 与类似于Raf的蛋白激酶CTR1协同负调控乙烯反应。EIN2和EIN3/EILs位于CTR1下游, 正调控乙烯反应。两个F-box蛋白EBF1和EBF2通过泛素/26S蛋白体降解途径调控EIN3的稳定性。5’→3’的外切核酸酶EIN5通过启动EBF1和EBF2 mRNA的降解, 拮抗EBF1和EBF2对EIN3的负反馈调控。目前对于乙烯信号转导途径关键组分的生化功能和乙烯下游反应途径的了解甚少, 乙烯信号转导途径与其它途径之间还存在着广泛的交叉反应, 这些问题的解决将大大增加我们对乙烯信号转导途径的了解。

Abstract: The gaseous plant hormone ethylene regulates a variety of developmental process and biotic and abiotic stress response in plant. During the past decade, molecular genetic studies on the model plant Arabidopsis have established a linear signal transduction pathway from signal perception on the endoplasmic reticulum membrane to transcriptional regulation in the nucleus. Ethylene receptor family in Arabidopsis consists of five components, including ETR1, ERS1, ETR2, ERS2 and EIN4, at least one of which, ETR1, was reported to localize on endoplasmic reticulum, and negatively regulates ethylene response by forming a complex with Raflike kinase CTR1. Downstream of CTR1 are EIN2 and EIN3/EILs, which positively regulate ethylene response.In the absence of ethylene signal, EIN3 is quickly degraded through an ubiquitin/26S proteasome pathway mediated by two F-box proteins, EBF1 and EBF2. EIN5, a 5’→3’ exoribonuclease, antagonizes the negative feedback regulation on EIN3 by promoting EBF1 and EBF2 mRNA decay. Despite the recent advances on the understanding of plant response to ethylene, many aspects of the ethylene signaling pathway remain unknown, especially the biochemical nature and the regulatory mechanisms of key pathway components, as well as the molecular basis of various interactions between the ethylene response pathway and other signaling pathways. In the coming years the research in this fast advancing field might provide much of the needed answers to these problems.