Plastid Extensions and Connections in Vascular Plants

维管植物中的质体延伸和连接

• 批准号: 9808101
• 负责人: Maureen Hanson
• 金额: $ 20万
• 依托单位: Cornell Univ - State: AWDS MADE PRIOR MAY 2010
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2001-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9808101&HistoricalAwards=false
• 关键词: Plastid; Extensions; Connections; Vascular; Plants

9808101HansonPlastids develop into a variety of forms in different tissues of the vascular plant, reflecting the variety of important functions these organelles perform. Plastids replicate by division and appear in textbooks as discrete, autonomous bodies. However, sporadic reports in the literature have described thin filamentous projections of the plastid envelope which sometimes connect with other plastids. These structures, rarely observable under the light microscope, have received little attention, and their very existence has sometimes been dismissed as an artifact. This project capitalizes on the observation that when green fluorescent protein (GFP) is expressed as a stromal protein in plastids, the structures are readily detected. Preliminary experiments have demonstrated that GFP can move through the tubular interconnections between plastids. This raises the possibility that these stroma-containing structures, denoted "stromules", permit exchange of other, functionally significant molecules. The general aim of this project is to characterize the stromules further and to probe their as yet unknown role in plastid function and plant cell biology. A thorough characterization of the stromules with regard to abundance, size, and degree of interconnections in different cell types during their cell cycle and development and under environmental stress will be carried out in the model plant Arabidopsis by light and electron microscopy. Transgenic plants will be produced that encode either GFP or blue fluorescent protein in their plastid genomes for future studies that will be undertaken to monitor the degree of transfer of different classes of proteins between plastids in hybrid cells. The interaction in vivo of stromules with other subcellular structures will also be examined.

质体在维管植物的不同组织中发育成多种形式，反映了这些细胞器所执行的重要功能的多样性。质体通过分裂进行复制，在教科书中以独立自主的实体出现。然而，文献中零星的报道描述了有时与其他质体连接的质体包膜的细丝状突起。这些结构很少在光学显微镜下观察到，很少受到关注，它们的存在有时被视为人工制品而被驳回。当绿色荧光蛋白（GFP）作为基质蛋白在质体中表达时，该结构很容易被检测到。初步实验表明，绿色荧光蛋白可以穿过质体之间的管状互连。这就提出了一种可能性，即这些含有基质的结构，称为“基质”，允许交换其他功能重要的分子。本项目的总体目标是进一步表征基质，并探索它们在质体功能和植物细胞生物学中的未知作用。在拟南芥模式植物中，我们将通过光镜和电子显微镜对不同细胞类型在细胞周期和发育过程中以及在环境胁迫下的基质丰度、大小和相互连接程度进行全面的表征。转基因植物将在其质体基因组中编码绿色荧光蛋白或蓝色荧光蛋白，用于未来的研究，以监测杂交细胞中不同种类蛋白质在质体之间转移的程度。体内基质与其他亚细胞结构的相互作用也将被研究。