Intrinsic Disorder, Energetic Coupling and Allostery

本项目研究蛋白质内在无序（ID）在介导蛋白质转录因子家族信号传导中的作用，这一过程被称为变构。通过测量糖皮质激素受体（GR）转录因子的一些天然变体的稳定性和DNA结合亲和力，并将这些值与细胞中的转录活性进行比较，该项目提供了一个框架，用于理解含有ID的蛋白质中的变构信号。由此产生的实验数据将用于构建变构的定量预测模型。拟议活动的知识价值是双重的。首先，这些研究使用生物物理学研究和活细胞功能测定提供了ID介导的变构的第一个系统分析。其次，这些研究挑战最近开发的合奏变构模型，旨在定量表征变构的内在稳定性的合作元素的结构和它们之间的相互作用能。因此，这项研究代表了对ID功能的先前定性和主要推测模型的进步，并提供了蛋白质如何以及为什么使用内在无序的第一个定量描述之一。该项目的更广泛的影响是双重的，并专注于研究，教育和这两个活动之间的桥梁。首先，该研究的主要目标是通过实验确定GR中存在的变构控制。然而，GR与雌激素（ER）、孕酮（PR）、雄激素（AR）和维生素D（VDR）受体共享结构，所有这些受体在雌激素依赖性细胞信号传导和调节中起着至关重要的作用。因此，从当前研究中获得的见解将直接影响对这些其他系统的理解。第二，研究的一个关键目标是推导出一个定量模型，该模型需要进行模拟和验证。作为两个以前的NSF提案的一部分，首席研究员已经开发了大量的基于计算机的课程工作，重点是动态生物系统的建模。作为当前研究的一部分开发的模型将直接整合到约翰霍普金斯大学的研究生和本科生课程中，因此不仅将在生物学学生的教育中发挥至关重要的作用，它将显着扩大生物学学生？获得计算方法和技术。

Intrinsic Disorder, Energetic Coupling and AllosteryThe current project investigates the role of protein intrinsic disorder (ID) in mediating signaling in the transcription factor family of proteins, a process known as allostery. By measuring the stability and DNA binding affinity for a number of naturally occurring variants of the glucocorticoid receptor (GR) transcription factor and comparing these values to the transcriptional activity in cells, this project provides a framework for understanding allosteric signaling in proteins containing ID. The resulting experimental data will be used to construct a quantitative, predictive model of allostery. The intellectual merits of the proposed activities are two-fold. First these studies provide the first systematic analysis of ID-mediated allostery using both biophysical studies and live cell assays of function. Second, these studies challenge a recently developed ensemble allosteric model designed to quantitatively characterize allostery in terms of the intrinsic stabilities of cooperative elements of structure and the interaction energies between them. As such, this research represents an advance over previous qualitative and largely speculative models for ID function, and provides one of the first quantitative descriptions of how and why proteins use intrinsic disorder.The broader impacts of the project are two-fold, and focus on research, education and the bridge between these two activities. First, the primary goal of the research is to experimentally determine the allosteric control present in GR. However, GR shares architecture with the estrogen (ER), progesterone (PR), androgen (AR), and vitamin D (VDR) receptors, all of which play a vital role in hormone-dependent cell signaling and regulation. As such, insights gained from the current research will directly impact understanding in these other systems. Second, a key objective of the research is to derive a quantitative model that is subject to simulation and validation. As part of two previous NSF proposals, the Principal Investigator has developed a significant amount of computer-based course work focuses on modeling of dynamic biological systems. The models developed as part of the current research will be directly integrated into the graduate and undergraduate curriculum at Johns Hopkins University, and thus will not only play a vital role in the education of biology students, it will significantly expand the biology students? access to computational methods and technologies.