THREE DIMENSIONAL RECONSTRUCTIONS OF THE CLEAVAGE FURROW

乳沟沟的三维重建

• 批准号: 8362553
• 负责人: JOHN SCHIEL
• 金额: $ 3.19万
• 依托单位: UNIVERSITY OF COLORADO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8362553
• 关键词: Actins; Actomyosin; Anaphase; Cell physiology; Cellular Structures; Cytokinesis; Cytoskeleton; Endosomes; Event; Excision; Funding; Grant; Laboratories; Lipids; Mediating; Mitosis; Modeling; National Center for Research Resources; Organelles; Principal Investigator; Recycling; Regulation; Research; Research Infrastructure; Resources; Role; Source; Staging; Tomogram; United States National Institutes of Health; Vesicle; Work; cost; 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. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. 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.

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 在分裂后期早期开始的胞质分裂代表有丝分裂的最后阶段，其中两个子细胞通过称为分裂的事件而分离。随着子细胞通过胞质分裂的进展，它们形成一个卵裂沟，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，需要分解以产生两个独立的子细胞。此外，已经表明再循环内体是成功的胞质分裂和胞质分裂所必需的。不幸的是，内体在卵裂沟的机制和功能仍不清楚。有两种假说试图解释内体在胞质分裂中的作用。第一个假设，管腔填充模型，表明同步内体融合在沟介导的子细胞的断裂。第二个假设，一个交付模型，提出了一个功能的内体在调节肌动蛋白细胞骨架的动力学和/或脂质组成的犁沟通过交付内体囊泡。我们实验室和其他实验室的先前工作已经确立了内体再循环在介导晚期胞质分裂中的作用。Rab 11和FIP 3已被证明参与胞质分裂过程中内体再循环至卵裂沟的靶向。为了确定卵裂沟内Rab 11/FIP 3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。早期和晚期分裂末期沟断层图像的比较将产生什么细胞器填充沟在末期的感觉。此外，免疫电镜的使用将提供用于鉴定细胞器填充的卵裂沟。