Cell & Molecular Biology of High Capacity Calcium Sequestration in Plants

细胞

• 批准号: 9904562
• 负责人: Vincent Franceschi
• 金额: --
• 依托单位: Washington State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-08-01 至 2001-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9904562&HistoricalAwards=false
• 关键词: Cell; & Molecular; Biology; Capacity

Calcium oxalate crystal idioblasts are cells that are specialized for high capacity calcium sequestration. They provide an excellent model for elucidating the biology of calcium transport and accumulation in plants. To continue the characterization of specific components of the high capacity calcium sequestration system, the matrix protein (MP), a unique high capacity calcium binding protein specific to crystal idioblasts, will be characterized as to its role in the biophysical process of calcium oxalate precipitation. Using both in vivo and in vitro methods, bacterial expressed cloned MP will be studied to further elucidate the role of this novel protein. The effects of overexpression of the MP in E. coli cells will be studied in relation to the bacterium's ability to grow in the presence of elevated soluble calcium and changes in the level of endogenous calcium will be studied. These studies should further the understanding of the physiological function of the MP in calcium sequestration.While there is considerable information on the biophysical properties of calcium channels in plant cells, advances in our understanding require that calcium channel protein components be isolated and cloned from plants. Thus, the high capacity calcium accumulating cell type will be used to isolate cDNAs for a plant calcium channel(s) and allow the further study of the nature of the channel in the crystal idioblast system. An antibody that recognizes a calcium channel-like protein in plants will be used for initial studies of localization and expression patterns in developing crystal idioblasts and idioblast fractions.

草酸钙晶体成纤维细胞是专门用于高容量钙封存的细胞。它们为阐明植物中钙转运和积累的生物学提供了一个极好的模型。为了继续表征高容量钙封存系统的特定成分，将表征基质蛋白（MP），一种针对晶体成纤维细胞的独特高容量钙结合蛋白，以确定其在草酸钙沉淀的生物物理过程中的作用。将利用体内和体外方法，研究细菌表达的克隆 MP，以进一步阐明这种新型蛋白质的作用。将研究大肠杆菌细胞中 MP 过度表达与细菌在可溶性钙升高的情况下生长的能力的影响，并研究内源钙水平的变化。这些研究应进一步加深对 MP 在钙封存中的生理功能的理解。虽然关于植物细胞中钙通道的生物物理特性有大量信息，但我们理解的进步需要从植物中分离和克隆钙通道蛋白成分。因此，高容量钙积累细胞类型将用于分离植物钙通道的cDNA，并允许进一步研究晶体成纤维细胞系统中通道的性质。识别植物中钙通道样蛋白的抗体将用于对发育中的晶体成纤维细胞和成纤维细胞部分的定位和表达模式进行初步研究。