Gu X, Verma D P
Department of Molecular Genetics, Ohio State University, Columbus, 43210, USA.
EMBO J. 1996 Feb 15;15(4):695-704.
Cytokinesis in a plant cell is accomplished by the formation of a cell plate in the center of the phragmoplast. Little is known of the molecular events associated with this process. In this study, we report the identification of a dynamin-like protein from soybean and demonstrate that this protein is associated with the formation of the cell plate. Plant dynamin-like (PDL) protein contains 610 amino acids showing high homology with other members of the dynamin protein family. Western blot experiments demonstrated that it is associated with the non-ionic detergent-resistant fraction of membranes. Indirect immunofluorescence microscopy localized PDL to the cell plate in dividing soybean root tip cells. Double labeling experiments demonstrated that, unlike phragmoplast microtubules which are concentrated on the periphery of the forming plate, PDL is located across the whole width of the newly formed cell plate. Based on the temporal and spatial organization of PDL in the phragmoplast, we termed this protein 'phragmoplastin'. The data suggest that phragmoplastin may be associated with exocytic vesicles that are depositing cell plate material during cytokinesis in the plant cell.
植物细胞中的胞质分裂是通过在成膜体中央形成细胞板来完成的。对于与此过程相关的分子事件，人们了解甚少。在本研究中，我们报告了从大豆中鉴定出一种类发动蛋白，并证明该蛋白与细胞板的形成有关。植物类发动蛋白（PDL）含有610个氨基酸，与发动蛋白家族的其他成员具有高度同源性。蛋白质免疫印迹实验表明，它与膜的非离子去污剂抗性组分相关。间接免疫荧光显微镜将PDL定位在正在分裂的大豆根尖细胞的细胞板上。双重标记实验表明，与集中在正在形成的细胞板周边的成膜体微管不同，PDL位于新形成的细胞板的整个宽度上。基于PDL在成膜体中的时间和空间组织，我们将该蛋白命名为“成膜体蛋白”。数据表明，成膜体蛋白可能与在植物细胞胞质分裂期间沉积细胞板物质的胞吐小泡有关。
