PDF(Pubmed)
Abstract：
Discovering and engineering herbicide-resistant genes is a crucial challenge in crop breeding. This study focuses on the 4-hydroxyphenylpyruvate dioxygenase Inhibitor Sensitive 1-Like (HSL) protein, prevalent in higher plants and exhibiting weak catalytic activity against many β-triketone herbicides (β-THs). The crystal structures of maize HSL1A complexed with β-THs were elucidated, identifying four essential herbicide-binding residues and explaining the weak activity of HSL1A against the herbicides. Utilizing an artificial evolution approach, we developed a series of rice HSL1 mutants targeting the four residues. Then, these mutants were systematically evaluated, identifying the M10 variant as the most effective in modifying β-THs. The initial active conformation of substrate binding in HSL1 was also revealed from these mutants. Furthermore, overexpression of M10 in rice significantly enhanced resistance to β-THs, resulting in a notable 32-fold increase in resistance to methyl-benquitrione. In conclusion, the artificially evolved M10 gene shows great potential for the development of herbicide-resistant crops.
摘要：
发现和改造抗除草剂基因是作物育种的关键挑战。这项研究的重点是4-羟基苯基丙酮酸双加氧酶抑制剂敏感1样（HSL）蛋白，在高等植物中普遍存在，对许多β-三酮除草剂（β-THs）表现出弱的催化活性。阐明了与β-THs复合的玉米HSL1A的晶体结构，鉴定四个必需的除草剂结合残基，并解释HSL1A对除草剂的弱活性。利用人工进化方法，我们开发了一系列针对这四个残基的水稻HSL1突变体。然后，对这些突变体进行了系统评估，鉴定M10变体在修饰β-THs中最有效。从这些突变体中也揭示了HSL1中底物结合的初始活性构象。此外，M10在水稻中的过表达显着增强了对β-THs的抗性，导致对甲基苯基三酮的抗性显着增加32倍。总之,人工进化的M10基因显示出开发抗除草剂作物的巨大潜力。
