Recombinant Human GPBAR1 protein

GPBAR1 (G Protein-Bile Acid Activated Receptor 1), also known as TGR5. is a member of the G protein-coupled receptor (GPCR) family, first identified in 2002. It is activated by bile acids, particularly secondary bile acids like lithocholic acid (LCA) and its conjugated forms. Structurally, GPBAR1 features seven transmembrane domains characteristic of GPCRs and is expressed in various tissues, including the liver, intestine, gallbladder, immune cells, and adipose tissue, highlighting its role in systemic metabolic and immune regulation.

Functionally, GPBAR1 modulates energy homeostasis, glucose metabolism, and bile acid synthesis. Upon activation, it triggers intracellular signaling pathways (e.g., cAMP/PKA, MAPK) that influence enteroendocrine hormone secretion (e.g., GLP-1), promoting insulin sensitivity and mitochondrial energy expenditure. It also exerts anti-inflammatory effects by suppressing NF-κB signaling, linking it to inflammatory bowel disease and metabolic disorders. GPBAR1's involvement in cholesterol metabolism and bile acid circulation further connects it to liver diseases, such as cholestasis and non-alcoholic steatohepatitis (NASH).

Recombinant GPBAR1 protein, produced via mammalian or insect expression systems with tags (e.g., His, FLAG), retains native receptor conformation and activity. It is critical for in vitro studies, enabling ligand binding assays, receptor-ligand interaction analysis, and high-throughput drug screening. Structural studies using recombinant GPBAR1 have advanced the design of synthetic agonists/antagonists targeting metabolic syndromes, diabetes, and liver disorders. Its role in gut-liver axis communication and immune modulation also positions it as a therapeutic candidate for obesity-related inflammation and gastrointestinal pathologies. Overall, GPBAR1 recombinant tools are indispensable for deciphering its pathophysiology and developing precision therapies.