固氮根瘤菌利用“脂质几丁寡糖”（lipochitooligosaccharide）信号分子启动与植物根的共生关系。曾有人提出，菌根真菌也为这一过程分泌化学信号，但这些分子的身份过去却不清楚。现在，研究表明，与根瘤菌相似的是，菌根真菌的确产生“脂质几丁寡糖”。这些共生信号在多个科的植物物种中刺激“丛枝菌根”的形成，同时刺激根部发育。这些数据提供了关于植物根部“内共生”中信号作用机制的演化的一个更为详尽的画面，并且可能为在农业中利用这些活性分子铺平道路。（生物谷Bioon.com）
生物谷推荐原文出处：
Nature doi:10.1038/nature09622
Fungal lipochitooligosaccharide symbiotic signals in arbuscular mycorrhiza
Fabienne Maillet,Véréna Poinsot,Olivier André,Virginie Puech-Pagès,Alexandra Haouy,Monique Gueunier,Laurence Cromer,Delphine Giraudet,Damien Formey,Andreas Niebel,Eduardo Andres Martinez,Hugues Driguez,Guillaume Bécard& Jean Dénarié
Arbuscular mycorrhiza (AM) is a root endosymbiosis between plants and glomeromycete fungi. It is the most widespread terrestrial plant symbiosis, improving plant uptake of water and mineral nutrients. Yet, despite its crucial role in land ecosystems, molecular mechanisms leading to its formation are just beginning to be unravelled. Recent evidence suggests that AM fungi produce diffusible symbiotic signals. Here we show that Glomus intraradices secretes symbiotic signals that are a mixture of sulphated and non-sulphated simple lipochitooligosaccharides (LCOs), which stimulate formation of AM in plant species of diverse families (Fabaceae, Asteraceae and Umbelliferae). In the legume Medicago truncatula these signals stimulate root growth and branching by the symbiotic DMI signalling pathway. These findings provide a better understanding of the evolution of signalling mechanisms involved in plant root endosymbioses and will greatly facilitate their molecular dissection. They also open the way to using these natural and very active molecules in agriculture.
