Inhibition of RNase to attenuate fungal-manipulated rhizosphere microbiome and diseases

Mining microbial communities specifically disrupted by fungal rnase effectors.Phytopathogens utilize effector proteins to manipulate host immunity and promote niche colonization. Here, we show that the soil-borne pathogen Fusarium graminearum can manipulate the plant-associated rhizosphere microbiome through the virulence effector Fg12, which encodes a fungal-specific ribonuclease (RNase). Fg12 is widely distributed among various fungal pathogens, and its antibacterial function relies on RNase activity. Some Fg12-inhibited bacteria, both individually and in synthetic communities (Syncoms), can alleviate F. graminearum infection in soybean and alfalfa plants. Moreover, we employed structural modeling, molecular docking, and in vitro enzymatic assays to demonstrate that guanosine monophosphate (GMP) functions as an effective chemical inhibitor of Fg12. Notably, GMP efficiently inhibits the antibacterial activity of Fg12 and effectively attenuates fungal diseases in soybean and alfalfa. In conclusion, we demonstrate that a virulence effector of a fungal phytopathogen can interfere with the host microbiome and present GMP as a potential RNase inhibitor for attenuating plant fungal diseases.

挖掘受真菌核糖核酸酶（RNase）效应因子特异性扰乱的微生物群落。植物病原真菌通过效应蛋白操控宿主免疫并促进生态位定殖。本研究发现，土传病原真菌禾谷镰孢（Fusarium graminearum）可通过致病效应因子Fg12调控植物相关的根际微生物组，该效应因子编码真菌特异性核糖核酸酶（RNase）。Fg12广泛分布于多种真菌病原中，其抗菌功能依赖于核糖核酸酶活性。部分受Fg12抑制的细菌，无论是单独培养还是在合成群落（Syncoms）中，均可减轻禾谷镰孢对大豆与苜蓿植株的侵染。此外，本研究通过结构建模、分子对接及体外酶活实验证实，单磷酸鸟苷（GMP）可作为Fg12的有效化学抑制剂。值得注意的是，GMP可有效抑制Fg12的抗菌活性，并显著减轻大豆和苜蓿的真菌病害。综上，本研究证实植物病原真菌的致病效应因子可干扰宿主微生物组，并提出单磷酸鸟苷（GMP）作为一种潜在的核糖核酸酶抑制剂，用于防治植物真菌病害。