PDF(Pubmed)
Abstract：
Plant-associated fungi show diverse lifestyles from pathogenic to mutualistic to the host; however, the principles and mechanisms through which they shift the lifestyles require elucidation. The root fungus Colletotrichum tofieldiae (Ct) promotes Arabidopsis thaliana growth under phosphate limiting conditions. Here we describe a Ct strain, designated Ct3, that severely inhibits plant growth. Ct3 pathogenesis occurs through activation of host abscisic acid pathways via a fungal secondary metabolism gene cluster related to the biosynthesis of sesquiterpene metabolites, including botrydial. Cluster activation during root infection suppresses host nutrient uptake-related genes and changes mineral contents, suggesting a role in manipulating host nutrition state. Conversely, disruption or environmental suppression of the cluster renders Ct3 beneficial for plant growth, in a manner dependent on host phosphate starvation response regulators. Our findings indicate that a fungal metabolism cluster provides a means by which infectious fungi modulate lifestyles along the parasitic-mutualistic continuum in fluctuating environments.
摘要：
与植物相关的真菌表现出不同的生活方式，从致病到与宿主共生；然而，他们改变生活方式的原则和机制需要阐明。根真菌炭疽菌（Ct）在磷酸盐限制条件下促进拟南芥的生长。这里我们描述了一种Ct菌株,指定为Ct3，严重抑制植物生长。Ct3的发病机理是通过激活宿主脱落酸途径，通过与倍半萜代谢产物生物合成相关的真菌次级代谢基因簇，包括botrydial。根感染过程中的簇激活会抑制宿主养分吸收相关基因并改变矿物质含量，提示在操纵宿主营养状态中的作用。相反，集群的破坏或环境抑制使Ct3有益于植物生长，以依赖于宿主磷酸盐饥饿反应调节剂的方式。我们的发现表明，真菌代谢簇提供了一种方法，通过该方法，感染性真菌可以在波动的环境中沿着寄生互生连续体调节生活方式。
