植物乙酰乳酸合成酶抑制剂作用方式及机理研究进展

Research progress on the mode and mechanism of action of plant acetolactate synthase inhibitors

以拟南芥Arabidopsis thaliana等植物为主要对象,系统评述了乙酰乳酸合成酶(ALS)抑制剂在作用靶标、选择性机制、毒性机理及化学杀雄作用等方面的研究进展。ALS是磺酰脲类、咪唑啉酮类等多种除草剂的共同作用靶标,最新研究又发现苯磺隆、酰嘧磺隆等多种ALS抑制剂可作为敏感植物的化学杀雄剂。目前该研究领域的薄弱环节是ALS抑制剂的毒性机理,先后提出了支链氨基酸饥饿、核酸合成受阻、ALS底物积累、养分转运障碍、无氧呼吸等假说,但均未能被证实。借助高通量的代谢组学、转录组学、蛋白质组学检测技术将能够更全面地揭示ALS抑制剂的生理生化效应,为研究其毒性机理提供新证据。

The research progress on the mechanism of chemicals inhibiting acetolactate synthase（ALS）,including the target of inhibitors,selective mechanism,phytotoxicity mechanism,and gametocidal activity on cruciferous plants was summarized.ALS is the target of several herbicides,including sulfonylurea,imidazolinone,sulfonylamino-carbonyltriazolinone,triazolopyrimidine and pyrimidinylthio（or oxy）-benzoates.Recently,some ALS inhibiting-herbicides such as tribenuron-methyl and amidosulfuron were highlighted by their gametocidal activity on susceptible plant.However,the mechanism leading to phytotoxicity of ALS inhibitors is not understood.Some possible mechanisms including branched-amino acid starvation,repression of DNA synthesis,accumulation of ALS substrate,inhibition of photoassimilate translocation,anaerobic respiration etc.were hypothesized but no one was validated.In order to reveal new clues for study the phytotoxicity mechanism,more physiological and biochemical events in response to application of ALS inhibitors need to be discovered by using high-throughput analytical methods including metabolomics,transcriptomics,and proteomics.