THREE DIMENSIONAL RECONSTRUCTIONS OF THE CLEAVAGE FURROW

乳沟沟的三维重建

• 批准号: 8170851
• 负责人: JOHN SCHIEL
• 金额: $ 4.98万
• 依托单位: UNIVERSITY OF COLORADO
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2011-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8170851
• 关键词: Actins; Actomyosin; Anaphase; Computer Retrieval of Information on Scientific Projects Database; Cytokinesis; Cytoskeleton; Endosomes; Event; Excision; Funding; Grant; Institution; Laboratories; Lipids; Mediating; Mitosis; Modeling; Organelles; Recycling; Regulation; Research; Research Personnel; Resources; Role; Source; Staging; Tomogram; United States National Institutes of Health; Vesicle; Work; daughter cell; electron tomography; reconstruction; spatiotemporal; telophase

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Cytokinesis beginning in early anaphase represents the last stages of mitosis where two daughter cells become separated via an event termed abscission. As the daughter cells progress through cytokinesis they form a cleavage furrow that ingresses by the action of an actomyosin contractile ring. This forms a narrow cytoplasmic bridge that needs to be resolved to produce two separate daughter cells. Additionally, it has been shown that recycling endosomes are required for successful cytokinesis and abscission. Unfortunately, the mechanism and function of endosomes at the cleavage furrow remain unclear. Two hypotheses have been proposed that try to explain the role of endosomes during cytokinesis. The first hypothesis, a luminal filling model, suggests synchronized endosome fusion at the furrow mediates the scission of daughter cells. The second hypothesis, a delivery model, proposes a function for endosomes in the regulation of actin cytoskeleton dynamics and/or lipid composition at the furrow through the delivery of endosomal vesicles. Previous work from our laboratory and others have established a role for recycling endosomes in mediating late stage cytokinesis. Rab11 and FIP3 have been shown to be involved in targeting of recycling endosomes to the cleavage furrow during cytokinesis . To determine the spatiotemporal dynamics of Rab11/FIP3 associated endosomes within the cleavage furrow, we will use electron tomography to three dimensionally reconstruct the cleavage furrow. Comparison of early and late telophase cleavage furrow tomograms will yield a sense of what organelles populate the furrow during telophase. Additionally the use of immunoEM will provide for the identification of organelles populating the cleavage furrow.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 细胞分裂开始于后期早期，代表有丝分裂的最后阶段，其中两个子细胞通过称为脱落的事件分离。当子细胞通过胞质分裂进展时，它们形成卵裂沟，通过肌动球蛋白收缩环的作用进入。这形成了一个狭窄的细胞质桥，需要对其进行解析才能产生两个独立的子细胞。此外，研究表明，成功的胞质分裂和脱落需要回收内体。不幸的是，卵裂沟内体的机制和功能仍不清楚。已经提出了两种假设，试图解释胞质分裂过程中内体的作用。第一个假设是管腔充盈模型，表明沟处的同步内体融合介导了子细胞的分裂。第二个假设，即递送模型，提出了内体通过内体囊泡的递送来调节沟处的肌动蛋白细胞骨架动力学和/或脂质组成的功能。我们实验室和其他实验室之前的工作已经确定了回收内体在介导晚期胞质分裂中的作用。 Rab11 和 FIP3 已被证明参与胞质分裂过程中将循环内体靶向至卵裂沟。为了确定卵裂沟内 Rab11/FIP3 相关内体的时空动态，我们将使用电子断层扫描来三维重建卵裂沟。比较末期早期和晚期的卵裂沟断层扫描图将了解末期期间沟中存在哪些细胞器。此外，免疫电镜的使用将有助于鉴定卵裂沟内的细胞器。