Collaborative Research: Comparative analyses of structural designs underlying functional performance of the toughest spider silk

蜘蛛丝是自然界中最坚韧的材料，有望激发新一代高性能合成生物材料的灵感。在马达加斯加的热带雨林中，达尔文的树皮蜘蛛使用一种比任何其他已知蜘蛛生产的丝质坚韧得多的丝质，在河流和湖泊上织出巨大的圆网。这个项目的目的是了解达尔文的树皮蜘蛛是如何产生这种“超级”丝的，以及这种丝在这些巨大的蛛网中是如何发挥作用的。通过与近亲物种的比较，该项目将测试新发现的纺纱腺体修饰和达尔文树皮蜘蛛中发现的丝蛋白如何相互作用，产生超级坚韧的丝绸，以及这些特征是否是跨越河流纺制巨型网所必需的。从这些特殊的蜘蛛中获得的洞察力将有助于超级丝蛋白的开发，这些蛋白可以启发新的高性能材料的设计。学生和博士后研究人员将接受培训，通过在美国和马达加斯加直接参与该项目，以及通过开发各种课程的课程，包括由阿克伦大学生物仿生研究和创新中心提供的课程，进行跨学科研究。展示这些迷人蜘蛛的自然历史的公共宣传将提供一个将生物多样性研究与技术创新联系起来的平台。这些更广泛的影响将通过在佛蒙特州大学自然历史博物馆的展览和在洛厄尔国家历史公园的Tsongas工业史中心为5-9年级的学生举办的教育活动来实现。该项目将在比较框架内研究达尔文树皮蜘蛛(Caerostris Darwini)及其近亲的丝绸生产、结构和生物力学，以确定超韧性丝绸背后的关键设计特征，以及它们如何随网络生态进化。其目的是：1)量化牵引丝纤维的材料性质和卡罗斯特里丝网的运动学；2)表征构成卡罗斯特里牵引丝的结构蛋白质和纺丝腺体形态；以及3)发展卡罗斯特里丝属物种的系统发育，以推断极坚韧的丝绸的进化原因和后果。这项工作将丝蛋白的基因组和蛋白质分析与丝线的功能表征以及网络功能和蜘蛛生态的有限元建模相结合。由系统基因组分析提供的进化框架将测试哪些特征促进了超坚韧丝绸的起源，以及它对巨型蜘蛛网进化的影响。

Spider silks are the toughest materials in nature and hold immense promise to inspire a new generation of high-performance synthetic biomaterials. In the rainforests of Madagascar, Darwin's bark spider spins giant orb webs across rivers and lakes using a silk that is far tougher than silk produced by any other known spider. This project aims to understand how Darwin's bark spider produces such 'super' silk and how the silk functions in these giant webs. Through comparison to closely related species, the project will test how newly discovered spinning gland modifications and silk proteins found in Darwin's bark spider interact to produce super tough silk, and if those features are necessary to spin giant webs across rivers. Insight gained from these exceptional spiders will aid in the development of super-silk proteins that can inspire the design of new high-performance materials. Students and postdoctoral researchers will be trained to conduct interdisciplinary research, through direct participation in the project in the US and Madagascar, and through the development of curriculum for a variety of courses, including those offered by The University of Akron's Biomimicry Research and Innovation Center. Public outreach showcasing the natural history of these engaging spiders will provide a platform for linking the study of biodiversity to technological innovation. Such broader impacts will be achieved through an exhibit at the University of Vermont's Natural History Museum and educational activities for students in grades 5-9 at the Tsongas Industrial History Center at Lowell National Historical Park.This project will investigate silk production, structure and biomechanics among Darwin's bark spider (Caerostris darwini) and its close relatives in a comparative framework to determine the key design features underlying super-tough silk and how they evolved with web ecology. The objectives are to: 1) quantify the material properties of dragline fibers and kinematics of Caerostris webs; 2) characterize the structural proteins and spinning gland morphology that form Caerostris dragline silk; and 3) develop a robust Caerostris species phylogeny to infer the evolutionary causes and consequences of extremely tough silk. The work integrates genomic and proteomic analyses of silk proteins with functional characterization of silk threads and finite element modelling of web function and spider ecology. An evolutionary framework provided by phylogenomic analyses will test which traits facilitated the origin of super-tough silk and its implications for the evolution of giant spider webs.