寻找新驱虫剂的工作一直受阻于对DEET (N,N-diethyl-meta-toluamide)的作用机制缺少一致的认识,后者60多年来一直是主要驱虫剂。
现在,Anandasankar Ray及同事识别出了介导DEET作用的关键成分:它们是一个高度保守的受体(Ir40a蛋白)和一组见于果蝇触角中一个小坑样结构内的感觉神经元。
除了自然出现或已经被批准用于人类的化学物质外,作者接着又在果蝇和蚊子中识别出了刺激相同神经回路、从而诱发厌恶感的其他化合物。
这些发现将改变DEET的廉价、安全和有效替代品的设计。(生物谷Bioon.com)
生物谷推荐的英文摘要
Nature doi:10.1038/nature12594
Odour receptors and neurons for DEET and new insect repellents
Pinky Kain,Sean Michael Boyle,Sana Khalid Tharadra,TomGuda,Christine Pham,Anupama Dahanukar& Anandasankar Ray
There are major impediments to finding improved DEET alternatives because the receptors causing olfactory repellency are unknown, and new chemicals require exorbitant costs to determine safety for human use. Here we identify DEET-sensitive neurons in a pit-like structure in the Drosophila melanogaster antenna called the sacculus. They express a highly conserved receptor, Ir40a, and flies in which these neurons are silenced or Ir40a is knocked down lose avoidance to DEET. We used a computational structure–activity screen of >400,000 compounds that identified >100 natural compounds as candidate repellents. We tested several and found that most activate Ir40a+ neurons and are repellents for Drosophila. These compounds are also strong repellents for mosquitoes. The candidates contain chemicals that do not dissolve plastic, are affordable and smell mildly like grapes, with three considered safe in human foods. Our findings pave the way to discover new generations of repellents that will help fight deadly insect-borne diseases worldwide.