Structure/Function of Protein Tyrosine Phosphatases

蛋白质酪氨酸磷酸酶的结构/功能

• 批准号: 8434661
• 负责人: Zhong-Yin Zhang
• 金额: $ 30.18万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-07-01 至 2017-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8434661
• 关键词: Active Sites; Address; Adopted; Affinity; Binding; Biochemical; Biochemical Genetics; Biological Assay; Cell Proliferation; Cell Survival; Cells; Cellular biology; Coupled; Coupling; Cytoplasmic Protein; Deuterium; Development; Disease; Disease Outcome; Docking; Elements; Enzyme Kinetics; Enzymes; Equilibrium; Etiology; Event; Family; Functional disorder; Gene Mutation; Goals; Growth Factor; Growth Factor Receptors; Hydrogen; Individual; Kinetics; LEOPARD Syndrome; Lead; Ligands; Link; MAPK3 gene; Malignant Neoplasms; Mass Spectrum Analysis; Mediating; Methods; Molecular; Molecular Conformation; Mutation; Neoplasms; Non-Receptor Type 11 Protein Tyrosine Phosphatase; Noonan Syndrome; Oncogene Proteins; Oncogenic; PTPN11 gene; Pathogenesis; Peptide Library; Peptides; Phenotype; Phosphoric Monoester Hydrolases; Physiological; Process; Property; Protein Tyrosine Kinase; Protein Tyrosine Phosphatase; Proteins; Proteomics; Receptor Protein-Tyrosine Kinases; Research; Risk; Role; Scaffolding Protein; Signal Pathway; Signal Transduction; Site; Site-Directed Mutagenesis; Solid; Solid Neoplasm; Src homology 2 domain-containing, transforming protein 1; Structure; Substrate Specificity; Tail; Testing; Therapeutic Intervention; Time; Translating; Tumor Suppressor Proteins; Tyrosine; Tyrosine Phosphorylation; Work; X-Ray Crystallography; base; combinatorial; combinatorial chemistry; developmental disease; disease phenotype; disease-causing mutation; gain of function; human disease; innovation; insight; interdisciplinary approach; leukemia; mutant; neoplastic; novel; novel therapeutics; programs; public health relevance; receptor; scaffold

DESCRIPTION (provided by applicant): The long-term objectives of this research program are to characterize the structure and function of protein tyrosine phosphatases (PTPs). The PTPs constitute a large family of signaling enzymes that together with protein tyrosine kinases (PTKs) modulate the cellular level of tyrosine phosphorylation. Disturbance of the normal balance between PTK and PTP activity results in aberrant tyrosine phosphorylation, which has been linked to the etiology of several human diseases, including cancer. Thus, a complete understanding of the physiological roles of protein tyrosine phosphorylation and how this process is deregulated in human diseases must necessarily encompass the characterization of PTPs. Such understanding may lead to the development of novel therapeutics that selectively target elements of signaling pathways for the treatment of human diseases. This competitive renewal focuses on SHP2 (Src homology 2 (SH2)-domain containing protein tyrosine phosphatase-2), which is the first bona fide oncoprotein identified in the PTP superfamily. SHP2 is ubiquitously expressed and positively regulates signaling from receptor tyrosine kinases through the activation of the Ras/ERK1/2 cascade. Consistent with its oncogenic role, germline autosomal dominant SHP2 mutations cause clinically similar LEOPARD syndrome (LS) and Noonan syndrome (NS), both of which are associated with increased risk of malignancy. In addition, somatic SHP2 mutations contribute to many forms of leukemia and solid tumors. However, although SHP2 mutations are associated with a number of developmental and neoplastic disorders, it remains unclear how SHP2 mutations alter cellular signaling to produce disease phenotypes. For example, NS or neoplasia-associated SHP2 mutants are constitutively active, resulting in gain-of-function effects. In contrast, mutations associated with LS reduce SHP2 phosphatase activity. These findings generated an enigma: how do SHP2 mutations with opposite effects elicit overlapping phenotypes? We hypothesize that pathogenic SHP2 mutations alter not only SHP2 phosphatase activity but also its molecular switching mechanism to drive disease outcomes and thus detailed understanding of the structure and function of SHP2 will reveal critical signaling events that underlie the diseases. The goals of this project ar to understand the molecular basis of disease-associated SHP2 mutations and to define the chain of molecular events coupling SHP2 dysfunction to the various LS abnormalities. A multidisciplinary approach, involving innovative combinations of X-ray crystallography, mass spectrometry, combinatorial chemistry, site-directed mutagenesis, enzyme kinetics, and cell biology will be employed to: 1) characterize the structural and biochemical properties of the LS mutants, and 2) define the signaling mechanisms mediated by the LS mutants. Successful completion of this project will create a solid framework for understanding how individual SHP2 mutations cause diseases and provide insight into novel points of therapeutic intervention for these diseases.

描述（由申请人提供）：该研究项目的长期目标是表征蛋白质酪氨酸磷酸酶（PTP）的结构和功能。 PTP 构成信号酶大家族，与蛋白酪氨酸激酶 (PTK) 一起调节酪氨酸磷酸化的细胞水平。 PTK 和 PTP 活性之间的正常平衡受到干扰会导致酪氨酸磷酸化异常，这与包括癌症在内的多种人类疾病的病因有关。因此，要全面了解蛋白质酪氨酸磷酸化的生理作用以及该过程在人类疾病中如何失调，必须涵盖 PTP 的表征。这种理解可能会导致开发出选择性靶向信号通路元件来治疗人类疾病的新疗法。此次竞争性更新的重点是 SHP2（包含蛋白酪氨酸磷酸酶 2 的 Src 同源 2 (SH2) 结构域），它是 PTP 超家族中发现的第一个真正的癌蛋白。 SHP2 广泛表达，并通过激活 Ras/ERK1/2 级联积极调节受体酪氨酸激酶的信号传导。与其致癌作用一致，种系常染色体显性 SHP2 突变会导致临床上类似的 LEOPARD 综合征 (LS) 和努南综合征 (NS)，这两种综合征都与恶性肿瘤风险增加相关。此外，体细胞 SHP2 突变会导致多种形式的白血病和实体瘤。然而，尽管 SHP2 突变与许多发育和肿瘤性疾病相关，但仍不清楚 SHP2 突变如何改变细胞信号传导以产生疾病表型。例如，NS 或肿瘤相关的 SHP2 突变体具有组成型活性，导致功能获得效应。相反，与 LS 相关的突变会降低 SHP2 磷酸酶活性。这些发现产生了一个谜：具有相反作用的 SHP2 突变如何引起重叠的表型？我们假设致病性 SHP2 突变不仅会改变 SHP2 磷酸酶活性，还会改变其驱动疾病结果的分子转换机制，因此对 SHP2 结构和功能的详细了解将揭示疾病背后的关键信号转导事件。该项目的目标是了解疾病相关 SHP2 突变的分子基础，并定义将 SHP2 功能障碍与各种 LS 异常耦合的分子事件链。涉及 X 射线晶体学、质谱、组合化学、定点诱变、酶动力学和细胞生物学的创新组合的多学科方法将用于：1）表征 LS 突变体的结构和生化特性，2）定义 LS 突变体介导的信号机制。该项目的成功完成将为理解个体 SHP2 突变如何导致疾病创建一个坚实的框架，并为这些疾病的治疗干预提供新的见解。