ISS: Unveiling the Mechanical Roles of Gravity and Buoyancy in Embryonic Brain and Heart Torsion

国际空间站：揭示重力和浮力在胚胎大脑和心脏扭转中的机械作用

• 批准号: 2025434
• 负责人: Zi Chen
• 金额: $ 40万
• 依托单位: Dartmouth College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-10-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2025434&HistoricalAwards=false
• 关键词: ISS; Unveiling; Mechanical; Roles; Gravity

Life originates in water. Most embryos develop in fluids with buoyancy, a force that only exists when there is gravity. Many species are pseudo-symmetric, and as such, breaking the left-right symmetry is essential for proper development. For example, axial rotation occurs in the development of many mammals and birds, and is one of the earliest developmental events that breaks the left-right symmetry. During axial rotation, the embryonic brain undergoes rotation to correctly place the organs. If it fails to do this correctly, significant birth defects can result. The research goal of this award is to understand how body forces such as gravity and buoyancy affect embryonic development and symmetry breaking. The project will examine how the absence of buoyancy and gravity change the growth and brain torsion in chicken embryos in experiments to be conducted on the International Space Station. These experiments, together with computational simulations, will be employed to identify the key mechanical factors driving axial rotation. The research results will be incorporated into solid mechanics and biomechanics courses, and the development of high school and undergraduate research experiences. Computational models will be made available on a website, and videos of this research will be uploaded to YouTube. An annual workshop will be held to host visitors and share scientific knowledge. The results of this work will benefit life on earth by increasing our understanding of embryonic development, which may lead to new ways to prevent birth defects. This research combines embryo experiments in space with computational modeling to identify the regulative role of physical forces in the early development. The team will study how changes in buoyancy and gravity can affect the growth of brain and heart, and how the development of brain and heart are interdependent during the process of embryonic brain torsion, an important symmetry-breaking event that is essential for establishing the correct body plan. Physical forces drive and regulate the twisting of the brain. Thus, the idea that brain torsion not only depends on body curvature (flexure) and the forces exerted by the vitelline membrane, but is also a result of heart development and body forces such as gravity and buoyancy will be explored. The hypothesis that buoyancy helps the heart and brain tube maintain the right morphology, and that the disturbance in buoyancy or heart development will be detrimental for symmetry breaking and embryonic development will be tested. The work will unveil new mechanical aspects of morphogenesis and develop new models for embryonic development that take into account the effects of body forces. Insights gained from this work will enhance our understanding of mechanics of embryogenesis, particularly the development of left-right asymmetry.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

生命起源于水。 大多数胚胎在具有浮力的流体中发展，这种力只有在具有重力时才存在。许多物种都是伪对称的，因此，打破左右对称性对于正确发育至关重要。例如，轴向旋转发生在许多哺乳动物和鸟类的发展中，并且是打破左右对称性的最早的发育事件之一。在轴向旋转过程中，胚胎大脑会经历旋转以正确放置器官。 如果无法正确执行此操作，可能会导致重大的先天缺陷。该奖项的研究目标是了解重力和浮力等身体力量如何影响胚胎发育和对称性破坏。该项目将研究在国际空间站进行的实验中，浮力和重力的缺失如何改变鸡胚胎的生长和脑扭转。这些实验以及计算模拟将被用于确定驱动轴向旋转的关键机械因素。研究结果将纳入固体力学和生物力学课程中，以及高中和本科研究经验的发展。计算模型将在网站上提供，该研究的视频将上传到YouTube。将举行年度研讨会，以接待访客并分享科学知识。这项工作的结果将通过增加对胚胎发展的理解来使地球上的生命受益，这可能会导致防止出生缺陷的新方法。这项研究将空间中的胚胎实验与计算建模相结合，以确定物理力在早期发育中的调节作用。团队将研究浮力和重力的变化如何影响大脑和心脏的生长，以及在胚胎脑扭转过程中大脑和心脏的发展如何相互依存，这是一个重要的对称性事件，这对于建立正确的身体计划至关重要。物理力驱动并调节大脑的扭曲。因此，脑扭转不仅取决于身体曲率（弯曲）和卵黄膜施加的力的想法，还将探索心脏发育和体力（例如重力和浮力）的结果。浮力有助于心脏和脑管保持正确的形态的假设，并且将测试浮力或心脏发育中的干扰对对称性破坏和胚胎发育有害。这项工作将揭示形态发生的新机械方面，并为胚胎发育开发新的模型，以考虑体力的影响。从这项工作中获得的见解将增强我们对胚胎发生力学的理解，尤其是左右不对称的发展。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力优点和更广泛影响的评估审查标准来通过评估来支持的。