CAREER: Evolutionary Origins of High Performance Major Ampullate Spider Silk: Development of an Integrated Bioscience Training Program

蜘蛛是地球上最多样化的动物之一，部分原因是它们的丝具有特殊的性质。这些特性在圆网蜘蛛身上得到了体现，它们使用牵引丝编织网的主干，牵引丝具有高拉伸强度和极高的韧性，超过了Kevlar®。因此，球织拖丝是材料科学的一个重要模型。然而，这是一种古老的丝，许多其他蜘蛛血统也纺拉丝。该项目旨在了解拖丝是如何通过关注其在遗传，生物力学和生态水平上的进化变化来进化出如此惊人的物理特性的。目的1比较从古代蜘蛛到狼蛛的拖丝的结构和功能，狼蛛纺出一种原始类型的丝。目的2检验超收缩，这是拖丝的一种新特性，可能使蜘蛛能够控制纤维的纺制，并测试关于它何时进化以及原因的关键假设。最后，目的3测试生态变化在拖丝使用中的作用，作为塑造其材料特性进化的力量。该项目将更好地了解一种生物材料，这种材料对动物的巨大多样性谱系的成功至关重要，并为仿生拖丝类似物的合成提供有价值的见解。该项目还将在阿克伦大学全新的综合生物科学博士课程的发展中发挥关键作用，直接支持和培训学生，并作为综合研究的“动手”案例研究，随后将是这些综合生物科学学生的第一批。

Spiders are among the most diverse animals on earth due, in part, to the exceptional properties of their silk. These properties are epitomized by orb weaving spiders that spin the backbones of their webs using dragline silk, which has a high tensile strength and extreme toughness, exceeding that of Kevlar®. Thus, orb weaving dragline silk is an important model for materials science. Nevertheless, it is an ancient silk and many other spider lineages also spin dragline silk. This project seeks to understand how dragline silk evolved such astonishing physical characteristics by focusing on its evolutionary change at the genetic, biomechanical, and ecological levels. Objective 1 compares the structure and function of dragline silk from ancient lineages of spiders to tarantulas, which spin a primitive type of silk. Objective 2 examines supercontraction, a novel property of dragline silk that may allow spiders to control fiber spinning, and tests key hypotheses about when it evolved and what causes it. Finally, Objective 3 tests the role of ecological changes in dragline silk use as a force shaping the evolution of its material properties. This project will yield a better understanding of a biomaterial critical to the success of a mega-diverse lineage of animals and also provide valuable insight for the synthesis of biomimetic dragline silk analogs. The project will also play a key role in the development of the University of Akron's brand new PhD program in Integrative Bioscience by directly supporting and training students and by serving as a "hands on" case study of integrative research that will be followed by the first cohorts of these Integrative Bioscience students.