Collaborative Research: Biomechanical mechanisms conferring wound resilience in single-celled organisms

创伤韧性是生物系统内稳态和生存所必需的一种共同特征。这个项目将在自由生活的单细胞生物体Stentor Blue uleus中确定伤口弹性原理，已知的是从剧烈的机械创伤中显示出强大的伤口愈合能力。该项目有可能为在合成细胞和软微型机器人中设计新功能-伤口弹性-奠定基础，并将使这些技术更适用于工业应用。这三位研究人员之间的合作为细胞生物学、工程学和数学建模领域的培训和劳动力发展提供了独特的机会。这项工作的结果将被纳入研究生课程和社交媒体，以提高公众对非模式生物的兴趣。所有研究人员将继续招募代表不足的少数族裔到STEM，通过针对K-12学生的外联和参加旧金山湾区科学节和每年在加利福尼亚州旧金山举行的Maker Fire。这个项目的总体目标是调查Stentor Blue uleus如何使用生物力学机制，既在创伤的上游预防伤口，又在创伤的下游利用生物力学机制从导致质膜开口的机械性伤口中强劲愈合。关注Stentor的理由是：1)Stentor是一种自由生活的单细胞有机体，在自然流动或捕食作用下可能受到高机械应力的环境中发现。原则上，这些细胞必须具有防止频繁伤害的特性，并在发生伤害时允许愈合。2)它的伤口愈合能力比大多数其他细胞更强。它能够从严重的伤口强劲恢复，并在24小时内从小到原始细胞大小的1/27的细胞碎片再生。这一特性允许在不立即导致细胞死亡的情况下扰乱损伤条件并测量其对修复过程的影响，从而为探测自我修复机制提供了坚固的平台。3)开展了高通量的基因敲除和损伤实验。Stentor的基因组已经测序，并开发了用于Stentor基因表达的分子操作工具，为从分子上了解Stentor伤口修复铺平了道路。该项目将测试细胞骨架在赋予细胞创伤抵抗力方面的作用，以及大规模机械力产生在补充生化愈合模式以关闭日益严重的伤口方面的作用。该项目结合了细胞生物学、微流体和机械生物学建模，涉及使用微流体产生精确的流动条件，以高通量的方式对细胞造成创伤，并开发集成生化和机械过程的数学模型。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Wound resilience is a common trait in biological systems necessary for homeostasis and survival. This project will identify wound resilience principles in the free-living single-celled organism Stentor coeruleus, known to display robust wound healing capacity from drastic mechanical wounds. This project has the potential to lay the foundation for engineering new functions—wound resilience—in synthetic cells and soft micro-robots, and will make the technologies more robust for industrial applications. The collaboration between the three investigators provides a unique opportunity for training and workforce development at the interface of cell biology, engineering, and mathematical modeling. Results from this work will be incorporated into graduate courses and social media to raise public interest in non-model organisms. All investigators will continue to recruit underrepresented minorities to STEM via outreach targeted to K-12 students and participation in the Bay Area Science Festival and the Maker Faire held yearly in San Francisco, CA.The overall goal of this project is to investigate how Stentor coeruleus employs biomechanical mechanisms both upstream of wounding for wound prevention, and downstream of wounding for robust healing from mechanical wounds that cause an opening in the plasma membrane. The rationales to focus on Stentor are: 1) It is a free-living unicellular organism found in environments that can be subject to high mechanical stresses due to natural flows or predation. In principle, these cells must possess properties that prevent frequent wounding and allow healing if wounding occurs. 2) Its wound healing capacity is more robust than most other cells. It is capable of recovering robustly from drastic wounds and regenerating from cell fragments as small as 1/27th of the original cell size in 24 hours. This property allows the perturbation of the wounding conditions and the measurement of their effect on the repair process without immediately causing cell death, thereby providing a robust platform for probing the self-repair mechanism. 3) High-throughput gene knockdown and wounding experiments have been developed. Stentor’s genome has been sequenced, and tools for molecular manipulation of Stentor gene expression have been developed to pave the way to a molecular understanding of Stentor wound repair. This project will test the role of the cytoskeleton in conferring wound resistance to the cell, and the role of large-scale mechanical force generation in complementing biochemical healing modes to close wounds of increasing severity. The project combines cell biology, microfluidics, and mechanobiology modeling, involving the use of microfluidics to generate precise flow conditions to inflict wounds on cells in a high throughput manner, and the development of mathematical models integrating biochemical and mechanical processes.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.