Cell Signaling by Protease-activated G Protein-coupled Receptors

蛋白酶激活的 G 蛋白偶联受体的细胞信号传导

• 批准号: 9919120
• 负责人: Joann Trejo
• 金额: $ 2.92万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-04-01 至 2023-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9919120
• 关键词: Arrestins; Binding; Biology; Bypass; Complex; Disease; Drug Targeting; Endosomes; Endothelium; Family member; G Protein-Coupled Receptor Signaling; G-Protein-Coupled Receptors; Goals; Inflammation; Knowledge; Laboratories; MAPK14 gene; Malignant Neoplasms; Mediating; Mediator of activation protein; Molecular; National Institute of General Medical Sciences; PAR-1 Receptor; Pathway interactions; Peptide Hydrolases; Permeability; Phosphorylation; Physiology; Proteins; Regulation; Research; Research Support; Role; Signal Transduction; Sorting - Cell Movement; Therapeutic; Ubiquitin; Ubiquitination; Work; drug development; experience; grasp; malignant breast neoplasm; mitogen-activated protein kinase p38; new therapeutic target; novel; programs; purinoceptor P2Y1; receptor; receptor function; trafficking; tumor progression

Summary The overall goals of our NIGMS-supported research program have been to delineate the regulatory mechanisms that control signaling by protease-activated receptor-1 (PAR1) and closely-related family members in normal physiology and disease. Our efforts have led to the discovery that ubiquitination of PAR1 promotes p38 mitogen-activated protein kinase (MAPK) signaling from endosomes and not lysosomal degradation. Ubiquitination of the P2Y1 receptor functions similarly. This work further revealed a distinct function for ubiquitination of PAR1 in p38-mediated endothelial barrier disruption. We then discovered a novel lysosomal pathway for PAR1 that is also relevant to other G protein-coupled receptors (GPCRs). Contrary to conventional view, we found that ubiquitination of certain GPCRs and canonical ubiquitin-binding ESCRTs are not required for receptor lysosomal degradation. We then identified ALG- interacting protein (ALIX) and arrestin-related domain containing protein-3 (ARRDC3) as key mediators of GPCR lysosomal sorting. The ALIX-dependent pathway bypasses the requirement for GPCR ubiquitination and is distinct from the canonical endosomal sorting complexes required for transport (ESCRT) lysosomal pathway. The ALIX and ARRDC3 pathway also appears to be dysregulated in cancer. The central premise for the proposed studies is that ubiquitination offers novel and diverse mechanisms for regulation of GPCR biology. A thorough understanding of the mechanism by which key regulators and mediators of ubiquitination regulate GPCR signaling and trafficking is essential for understanding dysregulated mechanisms in disease and for identifying new drug targets. The proposed studies will allow my research group to grasp a thorough understanding of novel concepts that we pioneered - that ubiquitination of GPCRs regulates signaling in normal physiology and is disrupted in disease. Our studies have raised many exciting questions and the most transformative research will be pursued. The p38 MAPK mediates inflammation, however it is not known how GPCR-activated, ubiquitin-driven p38 signaling promotes endothelial barrier permeability, a key feature of inflammation, and will be determined. There is a limited understanding of how GPCR endosomal signaling is regulated and is a challenge. Thus, we will define the mechanisms that regulate GPCR-activated, ubiquitin-driven p38 endosomal signaling. Several GPCRs sort through the ALIX-dependent pathway rather than canonical ESCRT, however, the key steps that segregate GPCRs into distinct lysosomal pathways are not known and will be delineated. ARRCD3 expression is either lost or suppressed in breast cancer, however it is not clear how ARRDC3 impacts PAR1 function or contributes to cancer progression and will be examined. We are well equipped to perform these studies given my laboratory’s expertise and experience delineating the function of ubiquitination in regulation of GPCR signaling and trafficking in normal physiology and disease.

概括 我们 NIGMS 支持的研究计划的总体目标是描绘监管 蛋白酶激活受体 1 (PAR1) 及其密切相关家族控制信号传导的机制 正常生理和疾病的成员。我们的努力发现，泛素化 PAR1 促进来自内体的 p38 丝裂原激活蛋白激酶 (MAPK) 信号传导，而不是 溶酶体降解。 P2Y1 受体的泛素化作用类似。这项工作进一步揭示了 PAR1 泛素化在 p38 介导的内皮屏障破坏中具有独特的功能。我们然后 发现了一种新的 PAR1 溶酶体途径，该途径也与其他 G 蛋白偶联受体相关 （GPCR）。与传统观点相反，我们发现某些 GPCR 和典型的泛素化 受体溶酶体降解不需要泛素结合 ESCRT。然后我们确定了 ALG- 相互作用蛋白 (ALIX) 和包含蛋白 3 (ARRDC3) 的视紫红质抑制蛋白相关结构域作为关键介质 GPCR 溶酶体分选。 ALIX 依赖性途径绕过了 GPCR 的要求 泛素化，与运输所需的典型内体分选复合物不同 (ESCRT) 溶酶体途径。 ALIX 和 ARRDC3 通路似乎在癌症中也失调。 拟议研究的中心前提是泛素化提供了新颖且多样化的机制 用于 GPCR 生物学的调控。全面了解主要监管机构和机构的机制 泛素化介体调节 GPCR 信号传导和运输对于理解至关重要 疾病和识别新药物靶点的失调机制。拟议的研究将允许 我的研究小组对我们开创的新概念有一个透彻的理解 GPCR 的泛素化在正常生理学中调节信号传导，但在疾病中被破坏。我们的研究 提出了许多令人兴奋的问题，并将进行最具变革性的研究。 p38 MAPK 介导炎症，但尚不清楚 GPCR 激活、泛素驱动的 p38 是如何发挥作用的 信号传导促进内皮屏障通透性，这是炎症的一个关键特征，并将被确定。 对 GPCR 内体信号传导如何调节的了解有限，并且是一个挑战。因此， 我们将定义调节 GPCR 激活、泛素驱动的 p38 内体信号转导的机制。 一些 GPCR 通过 ALIX 依赖性途径而不是规范的 ESCRT 进行排序，但是， 将 GPCR 分离到不同溶酶体途径的关键步骤尚不清楚，将予以描述。 ARRCD3 表达在乳腺癌中要么丢失，要么受到抑制，但尚不清楚 ARRDC3 是如何发挥作用的 影响 PAR1 功能或促进癌症进展，将进行检查。我们装备精良 考虑到我的实验室的专业知识和经验来进行这些研究，描述了 泛素化在正常生理和疾病中 GPCR 信号传导和运输的调节中。