CAREER: Structural and Biochemical Studies of the Tiam1 GEF, a Paradigm for Understanding Modular Protein Signal Transduction

职业：Tiam1 GEF 的结构和生化研究，理解模块化蛋白质信号转导的范例

• 批准号: 0953080
• 负责人: Ernesto Fuentes
• 金额: $ 105.28万
• 依托单位: University of Iowa
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0953080&HistoricalAwards=false
• 关键词: CAREER; Structural; Biochemical; Studies; Tiam1

The Rho-family of small guanosine triphosphatase (GTPase) proteins are essential for many basic physiological processes, including cell differentiation, division, chemotaxis, axonal development, and polarity. GTPases act as binary "on/off" switches and control communication within a cell. Guanine nucleotide exchange factors (GEFs) tightly control the active state of GTPases and coordinate their function. However, the fundamental mechanisms for how GEF proteins are regulated and how they direct GTPase signaling remain poorly understood. This project is focused on Tiam1, a large, modular GEF that specifically activates a GTPase (Rac1) that regulates cell polarity, adhesion, and migration. Under normal conditions Tiam1 GEF inhibits its own activity by protein-protein interactions and/or by phosphorylation. Upon activation, Tiam1 is capable of interacting with multiple protein targets and influencing many cell processes. In this study a combination of structural, biophysical, and biochemical approaches will be used to define the molecular basis of Tiam1 auto-inhibition, its activation, and its signaling specificity. The basic concepts learned from this project will enhance our understanding of signal transduction and provide new insights into the coordinated regulation of modular signaling proteins. In addition, this research will contribute to our understanding of diverse fields including protein allostery and dynamics, and promote the rational design of artificial scaffold proteins with desired regulatory features and functions.Broader Impacts: The major educational goal of this CAREER project is to expose faculty and students from primarily undergraduate institutions (PUI) to cutting-edge biophysics research. The PI will conduct a yearly "Biophysics Workshop" to establish research and education collaborations with PUI faculty throughout Iowa. These workshops will introduce PUI faculty and their students to modern experimental biophysics and provide access to the infrastructure necessary for them to expand their research capabilities. In addition, the PI will design an "Honors Tutorial Series" to introduce advanced high school and undergraduate students to web-based protein and gene analysis tools to enhance their summer research experience. The audience for this series will be drawn from ~100 high school and undergraduate students that participate in summer research programs across campus, including the SROP/McNair Scholars Program, Iowa Biosciences Advantage Program, Iowa First Nations Summer Program, and Secondary Student Training Program for high school students. Collectively, these activities will engage faculty and students, including members of minorities under-represented in science, in advanced biophysical research.This project is jointly supported by the Cellular Systems Cluster of the Molecular and Cellular Biosciences Division and the NSF EPSCoR Office

Rho家族的小鸟苷三磷酸酶（GT3）蛋白对于许多基本生理过程是必需的，包括细胞分化、分裂、趋化性、轴突发育和极性。 GTP酶充当二进制“开/关”开关并控制细胞内的通信。 鸟嘌呤核苷酸交换因子（GEFs）密切控制GTP酶的活性状态并协调它们的功能。然而，GEF蛋白如何调节以及它们如何指导GT3信号传导的基本机制仍然知之甚少。 该项目的重点是Tiam 1，一个大型的模块化GEF，专门激活调节细胞极性，粘附和迁移的GTdR（Rac 1）。 在正常条件下，Tiam 1 GEF通过蛋白质-蛋白质相互作用和/或磷酸化抑制其自身活性。 一旦激活，Tiam 1能够与多种蛋白质靶点相互作用，并影响许多细胞过程。 在这项研究中，结构，生物物理和生物化学方法的组合将被用来定义Tiam 1自抑制，其激活，其信号传导特异性的分子基础。 从这个项目中学到的基本概念将增强我们对信号转导的理解，并为模块化信号蛋白的协调调节提供新的见解。 此外，本研究将有助于我们理解不同领域，包括蛋白质变构和动力学，并促进合理设计的人工支架蛋白质所需的监管功能和functions.Broader影响：这个职业生涯项目的主要教育目标是暴露教师和学生从主要本科院校（PUI）的前沿生物物理学研究。 PI将每年举办一次“生物物理学研讨会”，与整个爱荷华州的PUI教师建立研究和教育合作。 这些研讨会将向PUI教师及其学生介绍现代实验生物物理学，并提供必要的基础设施，以扩大他们的研究能力。 此外，PI将设计一个“荣誉系列”，介绍先进的高中和本科生基于网络的蛋白质和基因分析工具，以提高他们的夏季研究经验。 该系列的观众将从约100名高中和本科生参加整个校园的夏季研究计划，包括SROP/麦克奈尔学者计划，爱荷华州生物科学优势计划，爱荷华州第一民族夏季计划和中学生培训计划高中生。 总体而言，这些活动将吸引教师和学生，包括在科学领域代表性不足的少数民族成员，参与先进的生物物理研究。