P-Protein Mutants: Tools to Analyze Phloem Protein Function

9727626汤普森韧皮部是必不可少的长距离运输的光合同化物从合成或再动员的网站到使用或存储的网站。 虽然韧皮部组织在解剖学和形态学上已经得到了很好的描述，但将易位细胞的结构成分与其功能联系起来仍有许多问题有待回答。 韧皮部蛋白（P蛋白）丝在许多高等植物的易位细胞的细胞质中形成完整的网络，但其功能尚未得到解决。 本项目的长期目标是将P蛋白的结构特征与韧皮部生物学联系起来。 PI正在利用南瓜属和黄瓜属物种中P蛋白之间的差异来确定这些蛋白质中保守特征的功能意义。 这些实验将是在转基因植物中进行功能测定的这些蛋白质的广泛突变分析的基础。 韧皮部细丝形成所需的结构组分也将在体外进行评估。 正在进行实验，以评估结合结构域中的韧皮纤维蛋白，并确定参与额外的蛋白质，特别是伴侣蛋白，在长丝形成的作用。 这些研究将增强我们对P蛋白的生物活性和这些蛋白的功能机制的理解。

9727626 Thompson Phloem is essential for the long distance transport of photoassimilates from the sites of synthesis or remobilization to the sites of use or storage. Although phloem tissue has been well described anatomically and morphologically, many questions remain to be answered to link structural components of the translocating cells to their function. Phloem protein (P-protein) filaments form an integral network in the cytoplasm of the translocating cells in many higher plants, yet their function is unresolved. The long term goal of this project is to relate the structural features of P-proteins to phloem biology. The PIs are utilizing the divergence between P-proteins in Cucurbita and Cucumis species to determine the functional significance of conserved features within these proteins. These experiments will be the basis for a broad mutational analysis of these proteins in functional assays performed in transgenic plants. Structural components that are required for phloem filament formation will also be assessed in vitro. Experiments are being conducted to evaluate binding domains in the phloem filament protein and to determine the involvement of additional proteins, especially the role of chaperones, in filament formation. These investigations will enhance our understanding of the biological activity of P-proteins and the mechanisms by which these proteins function.