Engineering the binding specificity of modular domains

 描述(申请人提供)：翻译后修饰(PTM)在调节蛋白质功能和调节蛋白质之间的相互作用中起着关键作用。众所周知，PTMS的恶化会导致许多疾病。组蛋白尾肽上的PTM决定染色质结构重塑和协调基因表达，这是表观遗传学的核心。这些组蛋白修饰被阅读器蛋白识别，这些阅读器蛋白通常包含与特定PTM结合的特定模块结构域，例如识别甲基化赖氨酸的色素域。了解这些PTM如何被识别的机制并开发工具来操纵这种识别对于开发新的治疗方法至关重要。在拟议的研究中，我们将开发和测试一种结合计算模拟和实验验证的综合方法来设计修饰多肽与其识别结构域之间的结合特异性。在目标1中，我们将对染色域的结合界面残基进行改造，以实现所需的结合特异性。在目标2中，我们的目标是设计色域对多重修饰多肽的识别。在目标3中，我们将在另一个模块化领域PHD领域测试所提出的工程策略的通用性。一旦这项研究完成，它将阐明修饰多肽的识别原理，并展示操纵这种识别的可能性，这将为表观遗传学中的信号转导开辟一条新的途径。

 DESCRIPTION (provided by applicant): Post translational modifications (PTMs) play critical roles in regulating protein functions and mediating protein-protein interaction. Deterioration of PTMs is known to cause many diseases. PTMs on histone tail peptides dictate chromatin structure remodeling and orchestrate gene expression, which is at the heart of epigenetics. These histone modifications are recognized by reader proteins that often contain particular modular domains binding to specific PTMs such as chromodomains recognizing methylated Lysine. Understanding the mechanisms of how these PTMs are recognized and developing tools to manipulate such recognition are critical for developing new therapeutics. In the proposed research, we will develop and test an integrated approach that combines computational simulation and experimental validation to design the binding specificity between the modified peptides and their recognition domains. In Aim 1, we will engineer the binding interface residues of chromodomains to achieve the desired binding specificity. In Aim 2, we aim to engineer chromodomains' recognition of multiply-modified peptides. In Aim 3, we will test the generality of the proposed engineering strategy on another modular domain, PHD domain. Once the proposed research is completed, it will illustrate the recognition principles of modified peptides and demonstrates the possibility of manipulating such recognition, which opens a new avenue of rewiring signal transduction in epigenetics.