玉米胚乳蛋白体的分子解析

籽粒的密度和硬度是决定玉米产量和品质的重要性状。储藏蛋白的合成与积累对该性状起决定性的作用。蛋白体是玉米主要储藏蛋白（醇溶蛋白）积累的特有细胞器，同时也是生物合成外源蛋白质的重要载体。目前，蛋白体生物合成和装配的分子机制还不清楚。本研究拟从亚细胞水平解析玉米胚乳蛋白体的蛋白质组，从总体上揭示蛋白体固在蛋白的组成和功能分类。前期研究表明，O1通过控制内质网的运动和形态影响蛋白体的装配，但其调控细节仍需阐明。通过系统筛选O1尾部结构域的互作蛋白建立O1蛋白互作网络，进一步揭示O1行使的生物学功能。结合蛋白体蛋白质组信息，选取内质网和蛋白体相关的关键蛋白进行功能分析。最后，在烟草体内诱导的蛋白体系统中，通过显性抑制、添加化学抑制剂等研究Myosin类马达蛋白、内质网和细胞骨架对蛋白体装配的影响，探究蛋白体合成装配的机制，为玉米籽粒品质相关性状的分子设计和创新提供理论依据。

Seed density and hardness play an essential role in maize seed quantity and quality. The synthesis and deposition of storage protein have effects on this trait. Protein body is an unique organelle for zeins accumulation in maize and also is a convenient vector for biosynthesis of the foreign proteins. However, the molecular mechanism underlying protein body synthesis and assembly is still unknown. We use a proteomic approach to dissect the proteome of maize endosperm protein body at the subcellular level. Previously, we indicated that Opaque1 influences protein body assembly by affecting ER morphology and motility, ultimately affecting endosperm texture. But the regulatory details through this process still need to be elucidated. By systematically screening and validating proteins that could interact with Opaque1 tail domain, we aim to construct an O1-interacting protein network, which will provide invaluable information for further analyzing O1 biological function. Combined with the information from the proteome of protein body, the key proteins involved in ER motility and protein body assembly will be selected for further functional analysis. Finally, the relationships between myosin motor protein/ER/cytoskeleton and protein body will be evaluated by using dominate-negative assay and chemical drugs in the induced protein body system in tobacco leaves. This will provide important information for dissecting the mechanism underlying endosperm protein body biosynthesis and assembly, and provide a solid basis for the molecular design and creation of maize germplasm in seed quality related traits.