Arrestin interactions with non-receptor binding partners

抑制蛋白与非受体结合伙伴的相互作用

• 批准号: 8458058
• 负责人: VSEVOLOD V. GUREVICH
• 金额: $ 28.51万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-04-01 至 2016-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8458058
• 关键词: Affect; Affinity; Alzheimer' s Disease; Apoptosis; Apoptotic; Arrestins; Binding; Biochemical; Biological Assay; Cell Death; Cell Proliferation; Cell Survival; Cells; Cessation of life; Co-Immunoprecipitations; Complex; Data; Disease; Dominant-Negative Mutation; Drug Targeting; Equilibrium; Exclusion; Family; G Protein-Coupled Receptor Signaling; G-Protein-Coupled Receptors; GTP-Binding Proteins; Human; Individual; Label; Life; Link; MAP Kinase Gene; MAP Kinase Modules; MAPK10 gene; MAPK8 gene; Malignant Neoplasms; Mediating; Methods; Mitogen-Activated Protein Kinases; Molecular; Mutagenesis; Neurodegenerative Disorders; Nuclear; Parkinson Disease; Pathway interactions; Peptides; Phosphotransferases; Play; Probability; Research; Role; Signal Pathway; Signal Transduction; Signaling Protein; Site; Spectrum Analysis; Testing; Therapeutic; Time; X-Ray Crystallography; arrestin3; base; design; interest; mutant; non-visual arrestins; novel; protein protein interaction; receptor; receptor binding; receptor internalization; response; scaffold; small molecule; tool; tumorigenesis; upstream kinase

DESCRIPTION (provided by applicant): Arrestins were first described as negative regulators of G protein-coupled receptor (GPCR) signaling via G proteins. New data show that the free and receptor-bound arrestins initiate signaling through MAP kinases, which regulate cell death, survival, and proliferation. In particular, both free and receptor- associated arrestin-3 scaffolds ASK1-MKK-JNK cascade, promoting JNK activation. Here we propose to elucidate the structural basis of arrestin-dependent activation of pro-apoptotic JNK family kinases and their activators MKK4/7 using biochemical and biophysical methods. The molecular mechanisms of the assembly of multi-protein signaling complexes (signalosomes) organized by arrestin-3 will be established, and arrestin-3 residues critical for JNK activation will be identified. Based on ths info, arrestin-3 mutants that bind ASK1, MKK and JNK, but do not promote JNK activation will be constructed. The potential of arrestin mutants with dramatically reduced ability to activate JNKs, several of which we already have, to protect cells against insults and prolong their survival will be tested. We have also constructed arrestin-3 mutants that activate JNKs more efficiently than parental wild type arrestin-3. We established the paradigm where arrestin-3-dependent JNK activation plays key role in cell survival. We will test the ability of hyperactive arrestin-3 mutants to facilitate cell death. We showed that inactive mutants tie up JNKs and upstream kinases in unproductive complexes, thereby acting in dominant- negative manner. We will test the potential of these mutants to protect cells and prolong their survival. Molecular toos that specifically increase or block pro-apoptotic signaling have therapeutic potential in disorders associated with excessive cell proliferation (e.g., cancer) or death (e.g., neurodegenerative diseases).

描述（由申请人提供）：抑制素首先被描述为通过 G 蛋白进行 G 蛋白偶联受体 (GPCR) 信号传导的负调节剂。新数据表明，游离的和受体结合的视紫红质抑制蛋白通过 MAP 激酶启动信号传导，调节细胞死亡、存活和增殖。特别是，游离的和受体相关的抑制蛋白-3支架 ASK1-MKK-JNK级联，促进JNK激活。在这里，我们建议使用生物化学和生物物理方法阐明促凋亡 JNK 家族激酶及其激活剂 MKK4/7 的抑制蛋白依赖性激活的结构基础。将建立由抑制蛋白-3组织的多蛋白信号复合物（信号小体）组装的分子机制，并鉴定对JNK激活至关重要的抑制蛋白-3残基。基于这些信息，将构建结合 ASK1、MKK 和 JNK 但不促进 JNK 激活的抑制蛋白 3 突变体。抑制蛋白突变体激活 JNK 的能力显着降低（我们已经拥有其中的几种），其保护细胞免受损伤并延长其生存的潜力将受到测试。我们还构建了抑制蛋白 3 突变体，其比亲本野生型抑制蛋白 3 更有效地激活 JNK。我们建立了视紫红质抑制蛋白 3 依赖性 JNK 激活在细胞存活中发挥关键作用的范例。我们将测试高活性的抑制蛋白-3 突变体促进细胞死亡的能力。我们发现，失活突变体将 JNK 和上游激酶束缚在非生产性复合物中，从而以显性失活方式发挥作用。我们将测试这些突变体保护细胞并延长其生存的潜力。特异性增加或阻断促凋亡信号传导的分子工具具有治疗疾病的潜力 与细胞过度增殖（例如癌症）或死亡（例如神经退行性疾病）有关。