Characterization of Clathrin Coated Vesicles Involved in Transport of Vacuolar Proteins in Plants

发育中的豌豆子叶是合成特异性 储备蛋白质 这些蛋白质的合成是 发育调节和组织特异性。 内 发育中豌豆子叶的薄壁细胞 蛋白质聚集在亚细胞的细胞器中， 由中央大液泡再分裂而产生的小体 最初存在于细胞中。 储备蛋白质是 在粗面内质网上合成并通过 高尔基体 这个实验室已经确定， 储备蛋白凝集素和其他液泡水解酶从 高尔基体包括网格蛋白包被的囊泡。 迄今为止， 可获得有关生物化学和功能的信息， 在植物系统中有被的囊泡。 拟议的研究将 利用存在于细胞中的包被囊泡的丰富来源， 发育豌豆子叶进行详细研究 它们的生物化学和功能。 这样做的直接目的是 研究的目的是表征网格蛋白轻链， 最近才在植物中发现。 一级序列 的轻链肽将被确定和机制 它们与重链的相互作用。 激酶 活性将在包被的囊泡中进行测定， 豌豆，以确定是否，在类似的动物系统， 轻链肽被磷酸化。 这些研究的结果将有助于我们了解 植物细胞的生物学，并将增强我们对 细胞内蛋白质转运的选择性。

Developing pea cotyledons are sites of synthesis of specific reserve proteins. The synthesis of these proteins is developmentally regulated and tissue specific. Within the parenchyma cells of the developing pea cotyledons the reserve proteins accumulate in sub-cellular organelles termed protein bodies which arise by sub-division of the large central vacuole originally present in the cells. The reserve proteins are synthesized on the rough endoplasmic reticulum and pass through the Golgi. This laboratory has established that the transport of the reserve protein lectin and other vacuolar hydrolases from the Golgi involves clathrin coated visicles. To date only limited information is available on the biochemistry and function of coated vesicles in plant systems. The proposed research will capitalize on the rich source of coated vesicles present in developing pea cotyledons to conduct a detailed study of aspects of their biochemistry and function. The immediate aims of this research are to characterize the clathrin light chain which has only recently been identified in plants. The primary sequences of the light chain peptides will be determined and the mechanism of their interaction with the heavy chain establshed. Kinase activities will be assayed in the coated vesicles from developing peas to determine whether, in similarity to animal systems, the light chain peptide is phosphroylated. The results of these studies will contribute to our knowledge of the biology of plant cells and will enhance our understanding of the selectivity of intracellular protein transport.