Manipulation of Cell Division with Static Magnetic Fields

用静磁场操纵细胞分裂

• 批准号: 9816986
• 负责人: James Valles
• 金额: $ 10万
• 依托单位: Brown University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2002-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9816986&HistoricalAwards=false
• 关键词: Manipulation; Cell; Division; Static; Magnetic

While many aspects of mitosis and cytokinesis have been elucidated, a vast amount of ongoing work focuses on these fundamental processes showing that much remains for discovery and resolution. Advances in microscopy and immunocytochemistry and techniques for the mechanical, optical and biochemical manipulation of cells and their components have traditionally led and continue to lead to substantial progress in this field. Valles and coworkers recently discovered that early cleavages (cell divisions) of embryos of the frog, Xenopus laevis, align with a large static magnetic field. The reorientation of cleavages depends systematically on field strength and orientation and does not depend on field gradients. This novel discovery presents opportunities for dissecting interactions between cells and magnetic fields and potentially developing a new tool for manipulating cells and studying cell division. The two specific objectives address these opportunities.Specific Objective 1: Determine the cleavage plane reorientation mechanism- While some systematics of this effect have been established, the mechanism has not. To achieve this goal, they will subject sets of frog embryos to magnetic fields during different periods of their cell cycle to identify when the influence of the magnetic field is strongest. They will use immunocytochemistry and confocal microscopy techniques to image the orientation and morphology of the microtubules of embryos exposed to the magnetic field to determine the influence of the magnetic field. Specific Objective 2: Determine whether microtubules in vivo align with a magnetic field -Cellular structures that are likely to be involved in the reorientation by magnetic field are those composed of microtubules. Microtubules comprise a major portion of the mitotic apparatus and recent measurements have shown that individual microtubules align in vitro in a magnetic field. Because of the importance of microtubules to the cleavage plane reorientation effect and to many other cell processes, the second goal is to image the microtubules in magnetic field exposed frog embryos to discern whether or not they are tending to align with the field direction. Immunocytochemistry and confocal microscopy techniques will be used to image the astral microtubules in field exposed, Xenopus embryos and compare the observed microtubule shapes to those calculated using the known properties of microtubules. If the microtubules do align then the possibility exists that other microtubule dependent cell processes can be manipulated with magnetic fields. If they do not, then the microtubules in living systems have properties that differ from their in vitro counterparts. Examining the source of such differences can provide insight into in vivo processes.Together, these experiments should provide fundamentally new insight into the interactions between magnetic fields and matter that might lead to general rules about those interactions and the potential for "magneto-manipulation" as a viable research tool.This project is jointly supported by the Cell Biology Program in the Division of Molecular Biosciences, Directorate for Biological Sciences (BIO) and the Office of Multidisciplinary Activities (OMA) in the Directorate for Mathematical and Physical Sciences (MPS).

尽管已经阐明了有丝分裂和细胞因子的许多方面，但大量持续的工作集中在这些基本过程上，表明发现和解决方案仍然存在很多。显微镜和免疫细胞化学的进步以及细胞机械，光学和生化操纵及其成分的技术的进步传统上导致并继续在该领域取得实质性进展。 Valles和同事最近发现，青蛙Xenopus laevis的胚胎的早期分裂（细胞分裂）与大型静态磁场对齐。切割的重新定位系统地取决于场强和方向，不取决于场梯度。这种新颖的发现为剖析细胞与磁场之间的相互作用提供了机会，并有可能开发一种用于操纵细胞和研究细胞分裂的新工具。特定目标1：确定裂解平面的重新定向机制 - 而这种效果的某些系统学已经确定，该机制尚未确定。为了实现这一目标，他们将在细胞周期的不同时期内将一组青蛙胚胎置于磁场，以确定磁场的影响何时最强。他们将使用免疫细胞化学和共聚焦显微镜技术来成像暴露于磁场的胚胎的微管的方向和形态，以确定磁场的影响。特定目标2：确定体内微管与磁场可能与磁场重新定位有关的磁场 - 细胞结构是否对齐是由微管组成的。微管包含有丝分裂设备的主要部分，并且最近的测量表明，单个微管在磁场中的体外对齐。由于微管对切割平面的重新定向效果的重要性以及对许多其他细胞过程的重要性，因此第二个目标是对磁场中的微管暴露的青蛙胚胎中的微管成像，以识别它们是否倾向于与田间方向保持一致。免疫细胞化学和共聚焦显微镜技术将用于成像现场暴露，异爪蟾胚胎中的星体微管，并将观察到的微管形状与使用微管的已知特性进行比较。如果微管确实对齐，则可能存在其他依赖微管的细胞过程的可能性。如果没有，那么生物系统中的微管具有与体外对应物不同的特性。 Examining the source of such differences can provide insight into in vivo processes.Together, these experiments should provide fundamentally new insight into the interactions between magnetic fields and matter that might lead to general rules about those interactions and the potential for "magneto-manipulation" as a viable research tool.This project is jointly supported by the Cell Biology Program in the Division of Molecular Biosciences, Directorate for Biological Sciences (BIO) and the Office of数学和物理科学局（MPS）中的多学科活动（OMA）。