Comparative biomechanics of intermediate filaments

仿生学是一个不断发展的科学领域，它从生物结构和过程中获得灵感来设计新产品。最著名的仿生学成功案例是维可牢尼龙搭扣®，它的灵感来自于小钩子，可以让毛刺搭在动物皮毛上。在我的实验室中进行的仿生研究主要集中在由生物体制成的结构材料上，这些材料可能会激发出具有独特和有用性能的新型合成材料的发明。在我的博士研究中，我研究了一种纤维材料，这种材料存在于盲鳗的防御性黏液中，盲鳗是一种海底生活的海洋食腐动物。我发现，虽然这些纤维在天然状态下柔软而富有弹性，但它们可以很容易地加工成具有类似蜘蛛丝特性的纤维，而蜘蛛丝以其超强的强度和韧性而闻名。这些实验导致了一项专利申请（目前正在审查中），也为一组称为“中间细丝”（或IFs）的纤维蛋白的结构和特性打开了一扇窗。这些纳米级的蛋白质细丝出现在粘液线中，构成了大多数动物细胞骨架的重要组成部分。它们还构成了哺乳动物更熟悉的“角蛋白”材料的大部分，其中包括柔软的皮肤外层和较硬的结构，如头发、指甲和角。通过对盲鳗黏液线的研究，我能够建立一个详细的模型，来解释动物使用IFs制造的各种各样的材料。该模型对IFs在细胞和角蛋白中的行为做出了一些预测。这里提出的研究的短期目标是通过检验一些最关键的预测来测试和完善模型。要做到这一点，我们将使用各种方便的材料，是基于IFs，包括盲鳗粘液线，神经，马蹄和鲸须。本研究的长期目标是提炼出一些基于if的材料的设计原则，并将其应用于既能提供生态可持续性又能提供卓越性能的工业材料的设计。

Biomimetics is a growing scientific field that takes inspiration from biological structures and processes for the design of novel products. The most famous biomimetic success story is Velcro®, which was inspired by the tiny hooks that allow burrs to hitch a ride on animal fur. The biomimetic research carried out in my lab focuses on structural materials made by organisms that could potentially inspire the invention of new synthetic materials with unique and useful properties. For my Ph.D. research, I worked on a fibrous material that occurs within the defensive slime of the hagfish, a bottom-dwelling marine scavenger. I discovered that these fibres, although soft and stretchy in their native state, could be easily processed into fibres with properties similar to spider silk, which is renowned for its superior strength and toughness. These experiments led to a patent application (which is currently under examination), and also opened a window into the structure and properties of a group of fibrous proteins called "intermediate filaments" (or IFs). These nano-scale protein filaments occur in slime threads and make up an important part of the cytoskeleton of most animal cells. They also form the bulk of the more familiar materials made by mammals called "keratins," which include the soft outer layer of skin and harder structures like hair, nail, and horn. Working with hagfish slime threads, which consist of nearly pure bundles of IFs,  I was able to formulate a detailed model that can explain the large diversity of materials that animals make using IFs. This model makes several predictions about the behavior of IFs in cells and keratins. The short-term goal of the research proposed here is to test and refine the model by examining some of its most critical predictions. To do this, we will use a variety of convenient materials that are based on IFs, including hagfish slime threads, nerves, horse hoof, and whale baleen. The long-term aim of this research is to distill out some of the design principles of IF-based materials, and apply them to the design of industrial materials that deliver both ecological sustainability and superior performance.