蔗糖合酶基因AbSUSs调控百山祖冷杉根毛发生的分子机制研究

百山祖冷杉（Abies beshanzuensis）是我国极度濒危的一级重点保护野生植物。百山祖冷杉属于菌根共生型植物，脱离共生关系难以利用根系吸收利用营养物质，导致人工繁育困难，因此，如何突破百山祖冷杉营养吸收障碍，是百山祖冷杉抢救保育的关键点。本项目拟以百山祖冷杉试管苗为研究对象，基于单细胞RNA测序技术揭示根毛细胞生长发育的分子动态轨迹，挖掘蔗糖信号调控百山祖冷杉根毛发生、发育及营养吸收利用的“分子开关”，构建以蔗糖合酶（sucrose synthase，SUSs）关键基因为中心的调控网络；分析AbSUSs转录水平及其蛋白水平的表达部位和丰度；鉴定AbSUSs酶催化机制及功能验证，解析AbSUSs调控根毛生长发育的分子机制。研究结果将阐明离体条件下百山祖冷杉根毛生长发育对蔗糖信号的响应机制及营养吸收策略，有望为百山祖冷杉等珍稀濒危植物资源的抢救保护与开发利用起到引领与示范作用。

Abies beshanzuensis, a critically endangered wild plant in the national protection grade I, is a mycorrhizal symbiosis type plant, which would be difficult to use the root system for nutrient absorption and utilization without the symbiosis, causing difficulty in artificial breeding. Therefore, how to break through the nutrient absorption barrier of A. beshanzuensis is the key point in the rescue and conservation. This project plans to use test-tube seedlings of A. beshanzuensis as the research object. Clarifying the molecular dynamics of root hair cell development through the single-cell RNA sequencing technology. Detecting the "molecular switch" regulated by sugar signal involved in root hair generation, development, and nutrient absorption and utilization to preliminary construct a regulatory network centering on the key sucrose synthase genes (AbSUSs). Clarifying the expression patterns at transcription levels and the protein expression location and abundance of AbSUSs. Preliminary determining the molecular mechanism of AbSUSs to regulate root hair growth and development, based on identifying catalytic mechanism and functional characteristics of AbSUSs enzyme. This project will clarify the response mechanism of root hair growth and development response to sucrose and nutrient absorption strategies in A. beshanzuensis in vitro, which play an exemplary role in the rescue, protection and utilization of A. beshanzuensis and other endangered plant resources.