Regulation of Talin Function in Amoeboid Cells

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。 在森林地面的树叶残骸中的许多居民之一是社会阿米巴。这些是在进化早期就从哺乳动物中分化出来并独立进化的古老生物。 社会性变形虫是相当了不起的--它们可以以单个细胞的形式存在，依靠生长在它们环境中的细菌生存，或者当食物变得稀缺时，它们可以聚集在一起形成一个多细胞有机体。 变形虫的生存和运动取决于它们粘附表面的能力，无论是它们的猎物细菌还是地面上的土壤，甚至是彼此。 这个项目的目标是了解简单的变形虫是如何粘附在表面上的。 这项工作的重点是talin，一种在哺乳动物和变形虫中发现的高度保守的蛋白质。 塔林蛋白是一种连接蛋白，它将粘附受体（细胞质膜中的蛋白质，识别特定表面（即细菌，其他变形虫））连接到细胞的内部骨架（称为细胞骨架）。 将受体连接到细胞骨架上，使细胞能够拉着表面，要么吞噬它的猎物细菌，要么沿着森林地面沿着。 该项目将提出有关talin作用机制的详细问题，即确定talin分子中对其功能所必需的区域，并寻找与talin结合的其他粘附蛋白。 它还将通过比较不同种类的变形虫（从最古老的到最近的）的talins的结构和功能来询问talin在社会变形虫中的作用是如何演变的。 从这个项目中获得的信息将揭示细胞如何与环境相互作用的基本原理，这是一种对细胞生长和生存至关重要的活动。 更广泛的影响。 该项目将为没有经验的学生（高中生、大学新生和大学生）提供实验室研究方面的实践培训机会。 总体目标是向学生介绍实验科学，并激发和培养他们的独立，批判性思维能力。 该项目包括一系列专门为具有各种技能水平的学生设计的迷你项目。 将采用一对一的苏格拉底方法：PI将单独教授学生各种方法，然后鼓励学生通过和回答有关塔林的具体问题，并在进行过程中提出自己的新问题。 该研究还将向学生介绍生物信息学方法在生物学中的作用以及蛋白质和生物体进化中的概念。 最后，该项目将成为促进国际合作和与拉丁美洲研究实验室进行科学交流的工具。 将编制讲座和实验室单元，供每年在巴西、乌拉圭和阿根廷举办的一系列细胞生物学和生物化学国际培训班使用，这些互动将成为发展科学合作的催化剂。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Intellectual merit. One of the many inhabitants in the leafy debris of the forest floors is social amoeba. These are ancient organisms that diverged and evolved independently from mammals quite early in evolution. Social amoeba are quite remarkable--they can exist as individual cells that subsist on the bacteria growing in their environment, or they can come together to form a multicellular organism when food becomes scarce. Amoeba survival and movement depends on their ability to stick to surfaces, either their prey bacteria or the soil on the ground or even each other. The goal of this project is to understand exactly how simple amoebae are able to adhere to surfaces. The focus of the work is on talin, a highly conserved protein found in both mammals and amoeba. Talin is a linker protein that connects adhesion receptors, proteins residing in the cell's plasma membrane that recognize specific surfaces (i.e. bacteria, other amoeba), to the cell's internal skeleton, called the cytoskeleton. Linking receptors to the cytoskeleton allows the cell to pull against the surface and either engulf its prey bacteria or move along the forest floor. The project will ask detailed questions about the mechanism of talin action, i.e. identifying regions of the talin molecule necessary for its function and searching for other adhesion proteins that bind to talin. It will also ask how the role of talin has evolved in social amoeba by comparing the structure and function of talins from different species of amoebae, from the most ancient to the most recent. The information gained from this project will reveal basic principles about how cells interact with their environment, an activity that is critical for their growth and survival. Broader impacts. The project will provide hands-on training opportunities in laboratory research for inexperienced students (high school students, college freshmen and sophomores). The overall goal is to introduce students to experimental science as well as stimulate and foster their independent, critical thinking skills. The project includes a series of mini-projects designed specifically for students with a wide range of skill levels. A one-on-one Socratic method will be employed: students will be individually taught various methods by the PI and then encouraged to work through and answer specific questions about talin, and formulate their own new questions as they proceed. The research will also introduce students to the power of bioinformatics approaches in biology and concepts in the evolution of proteins and organisms. Finally, the project will serve as a vehicle for stimulating international cooperation and scientific exchange with research laboratories in Latin America. Lectures and laboratory modules will be developed for presentation in a series of International Training Courses in Cell Biology & Biochemistry held annually in Brazil, Uruguay and Argentina, and these interactions will serve as a catalyst for developing scientific collaborations.