Hepatic GPR125: ligands and liver repair

肝脏 GPR125：配体和肝脏修复

基本信息

批准号：
10452011
负责人：
Blythe D Shepard
金额：
$ 15.6万
依托单位：
GEORGETOWN UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-06-01 至 2024-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10452011
关键词：
ARNT gene Adhesions Adult Agonist Bile Acids Bile fluid Biological Assay Cell Line Cell Maintenance Clustered Regularly Interspaced Short Palindromic Repeats Coupled Cues Development Diet Disease Drug Targeting Energy-Generating Resources Environment Epithelial Cells Extracellular Matrix FDA approved Family Female Functional Magnetic Resonance Imaging Future G-Protein-Coupled Receptors Gene Family Genome Glucose Guide RNA Health Hepatic Homeostasis Hormone Receptor Human Human body Image Immunofluorescence Immunologic Injury Intercellular Junctions Investigation Knock-out Knockout Mice Lead Ligands Link Liver Liver Regeneration Maintenance Mediating Metabolic Modeling Mus Mutate N-terminal NPBWR1 gene Natural regeneration Nature Organ Orphan Pathway interactions Pharmacology Physiological Physiology Play Process Reporting Sensory Sensory Receptors Site Stress Taste Buds Testing Tissues Transmembrane Domain Xenobiotics Zebrafish activation-induced cytidine deaminase adenoviral-mediated adhesion receptor basolateral membrane bile duct cholangiocyte injury and repair interest knock-down liver function liver injury liver repair male man member olfactory receptor planar cell polarity preclinical development prevent receptor regeneration following injury tissue repair

项目摘要

Project Summary G protein-coupled receptors (GPCRs) are 7 transmembrane domain proteins that aid in the maintenance of homeostasis by responding to cues produced by the internal and external environment. In humans, there are more than 800 known GPCRs, and while more than 20% of all FDA-approved drugs target GPCRs, the vast majority of these receptors are understudied. In fact, many of these uncharacterized ‘orphan’ receptors, termed GPRs, are expressed at extremely high levels in different tissues suggesting that they likely have important, yet unknown, physiological functions. The liver is the largest metabolic tissue in the human body and is responsible for a number of important functions including sensing and detoxifying xenobiotics, metabolizing glucose and other energy sources, and synthesizing and secreting bile acids. Thus, it is well- poised to take advantage of some sensory GPRs to aid in these processes. We recently identified a total of 57 GPRs that are expressed to varying degrees in the murine liver, including 7 with expression profiles that rival other well characterized receptors. One of these high expressing receptors is adhesion receptor GPR125 (ADGRA3). As a family, adhesion receptors have been linked to the maintenance of cell-cell junctions and have been reported to be activated by proteolytically cleavage of their non-covalently attached N-terminal domain. However, GPR125 is an atypical adhesion receptor with a mutated cleavage site and it is unclear if this receptor is activated via the conventional processes. GPR125 has been linked to the development of planar cell polarity in a Zebrafish model suggesting that this receptor may be involved in tissue repair in adult tissues. Using RNAscope and immunofluorescence, we have localized GPR125 to the basolateral membrane of cholangiocytes. Lining the bile ducts, cholangiocytes play a key role in the liver regeneration following injury. Thus, GPR125 is uniquely suited to contribute to this process. We hypothesize that GPR125, on the basolateral membrane of cholangiocytes, is activated by components of the extracellular matrix in order to contribute to liver repair following injury. This will be tested using the PRESTO-TANGO assay to deorphanize the receptor alongside a unique liver-specific knockout mediated by adenoviral delivery of CRISPR guide RNAs. Collectively, our discoveries will unveil new functions for a highly expressing, yet under-characterized, receptor and will set the stage for future physiological analysis in both mouse and man.

项目概要 G 蛋白偶联受体 (GPCR) 是 7 种跨膜结构域蛋白，有助于维持人类通过响应内部和外部环境产生的线索来实现体内平衡。超过 800 种已知的 GPCR，虽然 FDA 批准的所有药物中超过 20% 以 GPCR 为靶点，但大量事实上，这些受体中的大多数尚未得到充分研究。称为 GPR，在不同组织中以极高水平表达，表明它们可能具有重要但未知的生理功能肝脏是人体最大的代谢组织。并负责许多重要功能，包括感应和解毒外源物质，代谢葡萄糖和其他能源，合成和分泌胆汁酸，因此，它是很好的。我们最近发现了总共 57 个传感器，准备利用一些感觉 GPR 来帮助完成这些过程。 GPR 在小鼠肝脏中不同程度表达，其中 7 种表达谱与其他已明确表征的受体之一是粘附受体 GPR125。 (ADGRA3) 作为一个家族，粘附受体与细胞与细胞连接的维持有关。据报道，它们通过非共价连接的 N 末端的蛋白水解裂解而被激活然而，GPR125 是一种非典型粘附受体，具有突变的切割位点，目前尚不清楚是否存在这种情况。该受体通过常规过程激活，与 GPR125 的发展有关。斑马鱼模型中的平面细胞极性表明该受体可能参与成年组织修复使用 RNAscope 和免疫荧光，我们将 GPR125 定位于基底外侧膜。胆管细胞排列在胆管内，在肝脏再生中发挥着关键作用。因此，GPR125 非常适合促进这一过程。胆管细胞的基底外侧膜，被细胞外基质的成分激活，以有助于损伤后的肝脏修复这将使用 PRESTO-TANGO 实验进行测试以进行去孤儿化。该受体以及由腺病毒传递 CRISPR 介导的独特肝脏特异性敲除总的来说，我们的发现将揭示高表达但特征不足的新功能。受体，将为未来小鼠和人类的生理分析奠定基础。