Fundamental principles, limits, and function of ultrafast motion in single cell organisms

与流行的观念相反，生物学中运动最快的不是大型多细胞动物，如冲刺的猎豹或尤塞恩·博尔特，而是鲜为人知的微小单细胞生物。一个看似简单的细胞如何在没有肌肉的情况下产生非凡的力量和速度，仍然是一个悬而未决的问题。为了解决这一关键的知识缺口，该项目将研究一种极端单细胞生物（Spirostomum ambiguum），它利用人们知之甚少的分子马达、弹簧和闩锁来实现自然界中一些最快、最有力的运动。除了提高我们对细胞生物学的了解，这个项目的见解有可能在纳米工程方面取得突破，包括设计强大的微型机器人。PI将涉及细胞生物物理学研究的各个层次的年轻科学家，包括K-12，本科生和亚特兰大地区代表性不足的少数民族学生。PI还将与兰伯特高中合作，招收高中暑期实习生。研究成果和科学发现将通过大众媒体、YouTube和当地的亚特兰大科学节等大众媒体与更广泛的公众分享。螺口虫是一种相对较大的原生动物，通过可控触发的肌素移动。这是一个很好的模型系统，可以理解在单个细胞的规模上实现非凡的功率放大的基本问题。拟议的研究将整合生物学，物理学和数学的工具和技术，以开发一个多尺度框架，建立：i)通过基于钙的超分子蛋白质网络（即myoneme）产生力的控制原则；Ii)细胞材料特性和对环境的粘性能量耗散对速度的物理限制；iii)通过单细胞的超快速群体收缩进行集体流体动力学通信和传感。该项目由分子与细胞生物科学和生命系统物理学共同资助。该奖项反映了美国国家科学基金会的法定使命，并通过基金会的智力价值和更广泛的影响审查标准进行评估，认为值得支持。

Contrary to popular notion, the fastest movements in biology are not exhibited by large, multicellular animals such as a sprinting cheetahs or Usain Bolt, but by obscure, tiny microscopic single cell organisms. How a seemingly simple cell may generate extraordinary power and speed, without muscles, remains an open question. To address this critical knowledge gap, this project will study an extreme unicellular organism (Spirostomum ambiguum) that harnesses poorly understood molecular motors, springs and latches to achieve some of the fastest and most powerful movements in nature. In addition to advancing our knowledge of cell biology, insights from this project holds potential for a breakthrough in nanoscale engineering, including design of powerful micro-robots. The PI will involve young scientists across all levels in cell biophysics research including K-12, undergraduate and under-represented minority students in the Atlanta area. The PI will also host high-school summer interns in partnership with Lambert High School. Research findings and scientific discoveries will be shared with the broader public through popular media outlets including, popular media, YouTube, and the local Atlanta Science Festival. Spirostomum is a relatively large protozoan, which moves via a controllable-triggered myoneme. It is an excellent model system to understand fundamental questions of achieving extraordinary power amplification at the scale of a single cell. The proposed research will integrate tools and techniques from biology, physics and mathematics to develop a multi-scale framework that establishes: i) the governing principles for force generation through calcium-based supramolecular protein networks (i.e., myonemes); ii) the physical limits on speed imposed by both cellular material properties and viscous energetic dissipation to environment; and iii), collective hydrodynamic communication and sensing through ultra fast group contractions in single cells.This project is jointly funded by Molecular and Cellular Biosciences and the Physics of Living SystemsThis 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.