Promoting Receptor Protein Tyrosine Phosphatase Activity by Targeting Transmembrane Domain Interactions

通过靶向跨膜结构域相互作用促进受体蛋白酪氨酸磷酸酶活性

• 批准号: 10098384
• 负责人: Matthew J Lazzara
• 金额: $ 40.06万
• 依托单位: LEHIGH UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-20 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10098384
• 关键词: Affect; Agonist; Binding; Biological; Biology; Cancer cell line; Cell Line; Cells; Complement; Computer Models; Data; Development; Dimerization; Disease Progression; Engineering; Epidermal Growth Factor Receptor; Family; Generations; Goals; Health; Heterodimerization; Homo; Homodimerization; Human; Knowledge; Lead; Length; Malignant Neoplasms; Mass Spectrum Analysis; Measurement; Mediating; Membrane; Methods; Modeling; Molecular; Mus; Mutation; Oncogenic; Outcome; PTPRJ gene; Peptides; Phenotype; Phosphoric Monoester Hydrolases; Phosphorylation; Play; Point Mutation; Protein Dephosphorylation; Protein Tyrosine Phosphatase; Receptor Protein-Tyrosine Kinases; Regulation; Reporting; Research; Resistance; Role; Signal Pathway; Signal Transduction; Structure; Structure-Activity Relationship; System; Systems Biology; Tertiary Protein Structure; Testing; Therapeutic; Transmembrane Domain; Trefoil Motif; Tyrosine Kinase Inhibitor; Variant; attenuation; base; cancer cell; cancer type; design; dimer; embryonic stem cell; improved; insight; member; model building; monomer; mutant; novel therapeutic intervention; predictive modeling; prevent; programs; protein expression; receptor; response; therapeutic target; trafficking; tumor; tumor xenograft

PROJECT SUMMARY Receptor protein tyrosine phosphatases (RPTPs) play critical signaling regulatory roles in development, health, and disease progression. Despite the clear importance of RPTPs in signal transduction, very little is known about the structure-function relationships that underpin the regulation of their activity. The reported ability of RPTP homodimerization to antagonize their catalytic activity, however, presents potential opportunities to develop strategies to promote RPTP activity against their oncogenic receptor tyrosine kinase (RTK) substrates. We recently showed, using PTPRJ/EGFR as a model RPTP/RTK pair, that: (i) homodimerization of PTPRJ (also known as DEP1) is regulated by transmembrane domain interactions, and (ii) disrupting these interactions can antagonize PTPRJ homodimerization, reduce substrate EGFR phosphorylation, and antagonize EGFR-driven cell phenotypes. Here, we propose to build upon these new insights along three thematically interconnected, but non-overlapping, specific aims, with the ultimate goals of: (1) demonstrating that RPTP TM domain interactions are essential in regulating their activity and substrate access, and (2) developing a new therapeutic approach to promote RPTP activity against their oncogenic RTK substrates. In our first aim, we will determine the molecular determinants regulating the heterodimerization of PTPRJ with EGFR. These studies will be complemented by extending them to understand how PTPRJ TM domain mutants affect receptor trafficking and ultimate cell outcomes. In the second aim, we will design and select peptides capable of binding to PTPRJ TM domains and test their ability to disrupt PTPRJ homodimerization, promote PTPRJ activity against EGFR and other substrate RTKs, and selectively target human tumor xenografts in mice. In the third aim, we will identify other candidate RTK substrates whose regulation by PTPRJ depends upon TM domain-mediated heterodimerization, and determine how different cellular contexts predict the cell signaling and phenotype outcome of interfering with PTPRJ dimerization through TM domains. To do so, we will implement a systems biology approach based on data-driven computational modeling of phenotypic measurements and global mass spectrometry measurements of protein phosphorylation and expression in a panel of cell lines. This aim is motivated by an understanding that all RPTPs have multiple substrates and that variations in expression of those substrates among cells may lead to different outcomes when PTPRJ dimerization is disrupted. Ultimately, the studies proposed here stand to advance both our basic biological understanding of RPTP biology, which is critically needed, and to lead to new methods to target signaling through oncogenic RTKs that may be less susceptible to common mechanisms of acquired resistance to RTK inhibitors.

项目概要 受体蛋白酪氨酸磷酸酶 (RPTP) 在发育、健康、 和疾病进展。尽管 RPTP 在信号转导中的重要性显而易见，但人们知之甚少 关于支撑其活动调节的结构-功能关系。报告的能力 然而，RPTP 同二聚化以拮抗其催化活性提供了潜在的机会 制定策略以促进 RPTP 针对其致癌受体酪氨酸激酶 (RTK) 底物的活性。 我们最近使用 PTPRJ/EGFR 作为模型 RPTP/RTK 对表明：（i）PTPRJ 的同二聚化 （也称为 DEP1）受到跨膜结构域相互作用的调节，并且 (ii) 破坏这些 相互作用可以拮抗 PTPRJ 同二聚化，减少底物 EGFR 磷酸化，并且 拮抗 EGFR 驱动的细胞表型。 在这里，我们建议沿着三个相互关联的主题建立这些新见解，但是 不重叠的具体目标，最终目标是：(1) 证明 RPTP TM 域相互作用 对于调节其活性和底物获取至关重要，并且（2）开发新的治疗方法 促进 RPTP 对其致癌 RTK 底物的活性。 在我们的第一个目标中，我们将确定调节 PTPRJ 异二聚化的分子决定因素 EGFR。这些研究将通过扩展它们来补充，以了解 PTPRJ TM 结构域突变体如何 影响受体运输和最终的细胞结果。第二个目标，我们将设计和选择肽 能够结合 PTPRJ TM 结构域并测试其破坏 PTPRJ 同二聚化、促进 PTPRJ 针对 EGFR 和其他底物 RTK 的活性，并选择性地靶向人类肿瘤异种移植物 老鼠。在第三个目标中，我们将确定其他候选 RTK 底物，其 PTPRJ 的调节取决于 TM 结构域介导的异二聚化，并确定不同的细胞环境如何预测细胞 通过 TM 结构域干扰 PTPRJ 二聚化的信号传导和表型结果。为此，我们 将实施基于数据驱动的表型计算模型的系统生物学方法 蛋白质磷酸化和表达的测量和全局质谱测量 细胞系面板。这一目标的动机是了解所有 RPTP 都有多种底物，并且 PTPRJ 时，细胞间这些底物表达的差异可能会导致不同的结果 二聚化被破坏。 最终，这里提出的研究将增进我们对 RPTP 的基本生物学理解 生物学，这是迫切需要的，并通过致癌 RTK 开发靶向信号传导的新方法， 可能不太容易受到 RTK 抑制剂获得性耐药的常见机制的影响。