超过80%的陆地植物都能与丛枝真菌形成共生——丛枝菌根(AM）。这种共生关系的建立不仅依赖一套保守的共生上游基因发挥稳定的信号识别与传递作用，更需要植物精密地调控数目众多的共生下游基因，逐步引导真菌形成成熟的共生体。那么在此过程中，植物是如何抑制自身针对真菌的免疫反应的呢？共生结构的形成主要有哪些物质参与？这些物质又是怎样被植物精准地运输到共生界面的？为了有效回答这些问题，本项目立足于前期针对被子植物不同演化分支的两个代表性物种（单子叶植物水稻和双子叶植物番茄）的高通量转录组测序结果，优先选取与防御反应、细胞壁降解/合成、以及物质精准运输等功能密切相关的八个基因家族展开细致的基因家族演化分析，从中筛选在演化上呈现共生保守模式、且受到丛枝菌根共生强烈诱导或抑制的家族成员，通过基因敲除、转基因互补、组织定位、蛋白互作等一系列实验，全面探究这些基因家族成员参与调控丛枝菌根共生的分子机制。

Arbuscular mycorrhiza (AM) is a widespread symbiosis occurred in over 80% of land plants. This relationship with arbuscular mycorrhizal fungi (AMF) could assist plants in the assimilation of water and nutrients from the soil, which have likely played a key role in facilitating the earliest colonization of land by plants. Establishment of an efficient AM symbiosis not only relies on a set of highly conserved 'symbiosis upstream genes' that are responsible for the perception and transduction of AMF signals, but also requires plants to efficiently orchestrate hundreds of ‘symbiosis downstream genes’, which regulate the plant roots and AMF gradually entering into a mature symbiotic relationship for nutrient exchange. Currently, it is still poorly understood how plants are able to repress their defense responses elicited by fungal chitin, what the major components of symbiotic structures are and how plant can deliver the required materials to the surroundings of invaded fungal hyphae in an accurate manner. To unravel the molecular mechanisms behind these processes, we choose two representative species of angiosperm clades, Oryza sativa (rice) for monocots and Solanum lycopersicum (tomato) for dicots, to conduct high-throughput transcriptome sequencing, and the detected AM-responsive genes would be classified into various gene families according to their functions. Among gene families that likely involved in defense (including NBS-LRR and MLO gene families), cell wall degrading and synthesis (such as Subtilase and CESL families), and exocytosis/material delivery (such as Exo70, SYP13, VAMP72 and Vapyrin gene families), the conserved gene members that are highly upregulated or downregulated during AM symbiosis would be subjected to a collective of molecular experiments including quantitative-PCR, transgenic overexpression, Crispr gene-editing, GUS-staining, co-immunoprecipitation and bimolecular fluorescence complementation (BiFc), to fully explore their specific roles in regulating the development of AM symbiosis.