Guan Huirui, Liu Xin, Mur Luis A J, Fu Yanping, Wei Yahui, Wang Jing, He Wei
Key Laboratory of Resource Biology and Biotechnology in Western China, Department of Life Sciences, Northwest University, Xi'an 710069, China.
Shaanxi Institute for Food and Drug, Xi'an 710065, China.
J Fungi (Basel). 2021 May 20;7(5):400. doi: 10.3390/jof7050400.
Plants in the genus can live with the endophytic fungi sect. . Swainsonine, the mycotoxin produced by the endophyte render the host plant toxic and this has been detrimental to grazing livestock in both China and U.S.A. Despite previous efforts, many questions remain to be solved, such as the transmission mode and life cycle of host-endophyte symbiont, the biosynthesis pathway of swainsonine, and in particular the ecological role and evolution of such symbiosis. In this review, we compile the literature to synthesize ideas on the diversity of the symbiosis and propagation of the endophyte. We further compare the previous work from both sect. and other swainsonine producing fungi to orchestrate a more comprehensive biosynthesis pathway of swainsonine. We also connect swainsonine biosynthesis pathway with that of its precursor, lysine, and link this to a potential role in modulating plant stress response. Based on this we hypothesize that this host-endophyte co-evolution originated from the needs for host plant to adapt for stress. Validation of this hypothesis will depend on future research on endophytic symbiosis in and help in better understanding the roles of plant-endophyte symbiosis in non-Poaceae species.
该属植物可与内生真菌共生。内生真菌产生的霉菌毒素苦马豆素会使宿主植物有毒，这对中国和美国的放牧牲畜都造成了损害。尽管此前已做出努力，但仍有许多问题有待解决，例如宿主 - 内生菌共生体的传播方式和生命周期、苦马豆素的生物合成途径，尤其是这种共生关系的生态作用和进化。在本综述中，我们汇集文献以综合有关共生多样性和内生菌传播的观点。我们进一步比较了该属和其他产生苦马豆素的真菌之前的研究工作，以精心构建更全面的苦马豆素生物合成途径。我们还将苦马豆素生物合成途径与其前体赖氨酸的途径相联系，并将此与调节植物应激反应的潜在作用联系起来。基于此，我们假设这种宿主 - 内生菌共同进化源于宿主植物适应胁迫的需求。这一假设的验证将取决于未来对该属内生共生关系的研究，并有助于更好地理解植物 - 内生菌共生关系在非禾本科物种中的作用。
