Coordination of membrane and microtubule dynamics during cytokinesis in Arabidopsis thaliana

拟南芥胞质分裂过程中膜和微管动力学的协调

• 批准号: 195696156
• 负责人: Professorin Dr. Farhah Assaad, Ph.D.
• 金额: --
• 依托单位: Professur für Biotechnologie der Naturstoffe (BiNa)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/195696156?language=en
• 关键词: Coordination; membrane; microtubule; dynamics; during

Primary plant cell walls are laid down between anaphase and telophase in a transient membrane compartment referred to as the cell plate. The transport of vesicles to the cell plate is driven by a plant-specific array of microtubules and actin filaments, the phragmoplast. To avoid bisecting the nucleus, cytokinesis needs to be coordinated with the cell cycle in space and in time. A crucial question that arises is how membrane and cytoskeletal dynamics are coordinated and how they are regulated by cell cycle cues. In a genetic dissection of cytokinesis, we found that mutants in which cell plate biogenesis is impaired have defects in phragmoplast microtubule dynamics. We also found that the Sec1/Munc18 (SM) protein KEULE, involved in membrane fusion, is required for the reorganization of phragmoplast microtubules. We propose to further characterize membrane and microtubule organization and dynamics in a large collection of cytokinesis-defective mutants via antibody stains and live imaging, as well as electron and focused ion beam microscopy on cryofixed, freeze substituted samples. We then propose to test the hypothesis that KEULE interacts with microtubules, with microtubule-associated proteins, with motors and with the anaphase promoting complex. This would provide a model for how membrane fusion events are coordinated with microtubule dynamics and cell cycle progression cues in the context of plant cytokinesis.

植物初生细胞壁位于后期和末期之间的瞬态膜室（称为细胞板）中。囊泡向细胞板的运输是由植物特有的微管和肌动蛋白丝阵列（成膜体）驱动的。为了避免将细胞核一分为二，胞质分裂需要在空间和时间上与细胞周期协调。出现的一个关键问题是膜和细胞骨架动力学如何协调以及它们如何受到细胞周期线索的调节。在胞质分裂的遗传解剖中，我们发现细胞板生物发生受损的突变体在成膜体微管动力学方面存在缺陷。我们还发现参与膜融合的 Sec1/Munc18 (SM) 蛋白 KEULE 是成膜体微管重组所必需的。我们建议通过抗体染色和实时成像，以及对冷冻固定、冷冻替代样品的电子和聚焦离子束显微镜，进一步表征大量胞质分裂缺陷突变体中的膜和微管组织和动力学。然后，我们建议检验 KEULE 与微管、微管相关蛋白、马达和后期促进复合物相互作用的假设。这将为植物胞质分裂背景下膜融合事件如何与微管动力学和细胞周期进展线索协调提供一个模型。