Molecular steps in TAO kinase regulation

TAO 激酶调节的分子步骤

基本信息

批准号：
10185032
负责人：
MELANIE H. COBB
金额：
$ 32.8万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-09-01 至 2023-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10185032
关键词：
Binding Binding Sites Biochemical Biochemical Process Biological Biological Assay Bypass Catalytic Domain Cell Nucleus Cells Chemicals Complex Crystallization Cytoplasm Disinhibition Dissociation Drug Targeting Elements Enzymes Event Exhibits Foundations Future In Vitro Knowledge Literature MAP Kinase Gene MAP Kinase Kinase Kinase Membrane Modeling Molecular Nature Pathologic Pathway interactions Phosphoric Monoester Hydrolases Phosphorylation Phosphotransferases Physiological Processes Positioning Attribute Protein Kinase Protein phosphatase Proteins RNA Processing Recombinants Regulation Reporting Schistosoma Serine Signal Transduction Specificity Structure Surface Therapeutic Virus Diseases Work base drug development drug discovery experience in vivo influenza infection inhibitor/antagonist insight kinase inhibitor novel novel therapeutics p38 Mitogen Activated Protein Kinase protein complex reconstitution viral RNA

项目摘要

Despite their discovery over 20 years ago, TAO protein kinases (TAO1-3) remain understudied. In particular, we lack an understanding of the mechanisms regulating TAO activation, how they recognize substrates, and how these kinases contribute to key physiological processes. We originally identified TAOs through a large- scale effort to find membrane proximal components of MAPK cascades and showed that TAOs are MAP3Ks in the p38 pathway. Recent work now reveals that TAOs are essential for schistosome and viral infections and viral RNA processing and export from the nucleus. These findings suggest that TAOs are drug targets for a range of pathophysiological conditions and beg for a greater understanding of how their activities are controlled. Here, we propose to develop a paradigm for the biochemical regulation of TAO protein kinases through their integration with phosphoprotein phosphatase 1 (PP1). These results should advance future drug discovery efforts to provide new therapeutic entry points for treating a range of diverse pathological conditions. An obstacle in realizing their therapeutic potential is the limited knowledge of their regulation and partners. In searching for regulatory interactions, we found that TAOs directly bind PP1 and its R7 regulatory subunit. While PP1 dephosphorylates half the proteins in the cell, its activity is largely restricted within heteromeric complexes by regulatory subunits. Recent literature indicates that R7 maintains PP1 in an inactive state. We propose that TAOs modulate PP1 phosphatase activity via direct interactions and by R7 phosphorylation. The connection with PP1 offers TAOs wide opportunities to impact cellular control mechanisms. Our specific aims are to 1) determine how the TAO-PP1 complex regulates TAO activity; and 2) determine how TAO through R7 regulates PP1 activity. Biochemical and cell biological studies will take advantage of a model of a TAO2-PP1 complex based on our crystal structure of the TAO2 kinase domain that shows the PP1 binding motif on TAO. The relevance of this interaction is supported by our recent work revealing co-localization of TAO2 and PP1 in structures in the nucleus and the cytoplasm. Our extensive experience in identifying and characterizing TAOs, determining the structure of the TAO kinase domain, identifying chemically tractable inhibitors, and elucidating TAO-dependent pathways, since our discovery of these kinases, puts us in a unique position to determine biochemical processes that will provide a foundation for TAO kinases as subjects of drug development.

尽管有20年前的发现，但道蛋白激酶（TAO1-3）仍在研究中。特别是，我们对调节道的激活的机制缺乏了解，它们如何识别底物以及这些激酶如何促进关键的生理过程。我们最初是通过大规模努力来找到MAPK Cascades的膜近端成分的大规模识别的，并表明Taos是p38途径中的MAP3K。现在的工作现在表明，陶斯对于血块和病毒感染以及病毒RNA加工以及从细胞核出口至关重要。这些发现表明，陶斯是一系列病理生理状况的药物靶标，并乞求更多地了解其活动的控制方式。在这里，我们建议通过与磷酸蛋白磷酸酶1（PP1）的整合来开发一种范式调节道蛋白激酶的生化调节。这些结果应推进未来的药物发现努力，以提供新的治疗入口点，以治疗各种病理状况。意识到他们的治疗潜力的障碍是对他们的监管和伴侣的了解有限。在搜索调节性相互作用时，我们发现陶斯直接结合了PP1及其R7调节亚基。虽然PP1将细胞中的一半蛋白质去磷酸化，但其活性在很大程度上受到调节亚基的杂体复合物的限制。最近的文献表明，R7将PP1保持在不活动状态。我们建议陶斯通过直接相互作用和R7磷酸化来调节PP1磷酸酶活性。与PP1的联系为影响细胞控制机制提供了广泛的机会。我们的具体目的是1）确定道pp1复合物如何调节道的活性； 2）确定TAO通过R7如何调节PP1活性。生化和细胞生物学研究将基于我们的TAO2激酶结构域的晶体结构来利用TAO2-PP1复合物的模型，该结构显示了TAO上的PP1结合基序。我们最近的工作揭示了TAO2和PP1在细胞核和细胞质中的结构中的共定位，从而支持了这种相互作用的相关性。我们在识别和表征陶斯（Taos），确定陶激酶结构域的结构，识别化学诱导的抑制剂以及阐明tao依赖性途径方面的丰富经验，因为我们发现了这些激酶，使我们处于独特的位置，使生物化学过程能够确定陶氏酶开发的陶氏酶的基础。