STRUCTURE OF PLASMODESMATA (INTERCELLULAR PLANT JUNCTIONS)

Plasmodemata（植物细胞间连接）的结构

• 批准号: 6121818
• 负责人: VITALY H CITOVSKY
• 金额: $ 2.78万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-05-15 至 2000-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6121818
• 关键词: biomedical resource; communication behavior; microscopy; plants

We are studying the 3-dimensional structure of plant intercellular connections, the plasmodesmata (PD). Dr. Civotsky's laboratory sent Dr. Sosinsky grids containing thick and thin sections cut from embedded and sectioned material. These samples are 1) leaf tissue 2) purfied cell walls with plasmodesmata (PD) and 3) purified cell walls with PD treated with the detergent chaps. Dr. Sosinsky has collected 3 tilt series of sample 2. The first reconstruction just contained cell walls, so Dr. Sosinsky will collect more tilt series. She is presently examining the PD's in leaf tissue to compare with isolated, biochemically characterized PD's. In the past year, we have acquired five tilt series from preparations of purified cell walls containing plasmodesmota proteins. Three of the tilt series were from CHAPS (a detergent) treated cell walls while the other two tilt series were from preparations which were not detergent treated. Tomograms of each of the five tilt series were computed. Surprisingly, the plasmodesmota in all five tomograms did not look like models based on projection images. In models based on thin section images from both isolated plasmodesmota and ones found in leaf tissue, the plasmodesmota should resemble a barrel-shaped structure analogous to nuclear pore complexes. In the tomograpms, we found two elipsoidal elongated structures that span the cell wall longitudinally, but not radially. We will be recording tilt series from intact leaf tissue and consequently computing tomograms from these tilt series in order to assess if the plasmodesmota structure is barrel-shaped and a significant loss of pro teins in the structure have been lost during isolation (coordinating with the biochemistry of the project) or that the model based on thin section is incorrect and indeed, the plasmodesmota structure is not a solid cylinder.

我们正在研究植物间的三维结构 连接，plasmodesmata（PD）。 Civotsky博士的实验室发送了 Sosinsky博士网格，其中包含从 嵌入和切片的材料。 这些样品是1）叶组织2） 带有质desmata（PD）和3）纯化的细胞壁的净化细胞壁 用洗涤剂粉红色处理的PD。 Sosinsky博士收集了 3个倾斜系列样本2。第一个重建刚刚包含 细胞壁，因此Sosinsky博士将收集更多倾斜系列。 她是 目前正在检查叶组织中的PD，以与孤立的， 生化特征的PD。 在过去的一年中，我们获得了 五个倾斜系列，来自纯化的细胞壁的制剂 疟原虫蛋白。 倾斜系列的三个来自chaps（a 洗涤剂）处理的细胞壁，而其他两个倾斜系列是 从未经洗涤剂处理的制剂中。 每个的断层图 计算了五个倾斜系列。 令人惊讶的是， 所有五个断层图中的plasmodesmota看起来都不像基于模型 投影图像。 在基于两者的薄截面图像的模型中 分离的疟原虫及其在叶组织中发现 疟原虫应类似于类似于的桶形结构 核孔复合物。 在Tomograpm中，我们发现了两个Elipsoidal 纵向跨细胞壁的细长结构，但不是 径向。 我们将从完整的叶组织记录倾斜系列 因此，按顺序计算这些倾斜序列的断层图 评估疟原虫结构是否为桶形和 在结构中严重丢失了pro teins在 隔离（与项目的生物化学协调）或 基于薄片的模型是不正确的，实际上是 浆尾莫塔结构不是固体圆柱体。