https://scholar.dgist.ac.kr/handle/20.500.11750/295 Sat, 04 Apr 2026 10:33:22 GMT 2026-04-04T10:33:22Z https://scholar.dgist.ac.kr/handle/20.500.11750/58513 Title: Protein–Protein Interactions of Odorant and G Protein-Coupled Receptors: A BRET Analysis Approach Author(s): Choi, Ji Woo; Koo, JaeHyung Abstract: Odorant receptors (ORs), the largest subfamily of G protein-coupled receptors, are pivotal not only for olfactory detection in the nose but also for various biological functions in extra-nasal tissues. The functional characterization of ORs presents significant challenges, especially due to the difficulty of achieving their surface expression in in vitro systems. Research indicates that interactions between ORs and other receptors, as well as OR multimerization, are crucial for their membrane localization and the modulation of signaling pathways. Utilizing the bioluminescence resonance energy transfer (BRET) assay, a technique for investigating protein–protein interactions, our study quantifies the interactions between ORs and various receptors. This approach provides novel insights into OR molecular dynamics, emphasizing the role of OR multimerization. By exploring into these complexities, our work aims to enhance the understanding of cellular signaling mechanisms and promote the development of innovative therapeutic strategies. © The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature 2025. Mon, 31 Mar 2025 15:00:00 GMT https://scholar.dgist.ac.kr/handle/20.500.11750/58513 2025-03-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/58512 Title: Image-Based cAMP Sensor Assay for Analyzing Odorant Receptor Activity Author(s): Choi, Ji Woo; Koo, JaeHyung Abstract: Odorant receptors (ORs), the largest subfamily of G-protein-coupled receptors (GPCRs), are transmembrane proteins essential for olfactory perception. Recent research has revealed their expression in nonolfactory tissues, highlighting their potential as novel drug targets. However, the functional analysis of ORs beyond nasal tissues is constrained by limited availability of suitable ligands. Conventional in vitro methods for studying OR–ligand interactions via cAMP often face challenges in large-scale applications. This protocol introduces an advanced cAMP assay employing the Pink Flamindo sensor, a cAMP fluorescence sensor that normally does not exhibit fluorescence but shows fluorescence when combined with cAMP. This enables the real-time visualization of OR–ligand interactions through an imaging-based method. This technique significantly aids in the deorphanization of ORs. Mon, 31 Mar 2025 15:00:00 GMT https://scholar.dgist.ac.kr/handle/20.500.11750/58512 2025-03-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/58362 Title: Yellow Fluorescent Protein Quenching Assay for Analyzing Odorant Receptor Activity Author(s): Choi, Ji Woo; Koo, JaeHyung Abstract: Odorant receptors (ORs), recognized as the largest subfamily of G protein-coupled receptors (GPCR), are increasingly identified as membrane proteins crucial not only in nasal but also in various extra-nasal biological processes. However, researching the functions of these extra-nasal ORs is challenging due to the limited availability of ligands, posing a significant barrier to comprehensive studies. Large-scale screening with in vitro assays, such as the halide-sensitive yellow fluorescent protein (YFP) quenching assay, is crucial for deorphanizing ORs. This protocol employs the YFP quenching assay to identify OR-ligand interactions, thereby advancing OR deorphanization research. © The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature 2025. Mon, 31 Mar 2025 15:00:00 GMT https://scholar.dgist.ac.kr/handle/20.500.11750/58362 2025-03-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/57468 Title: Comprehensive Transcriptomic Analysis Reveals Cell-Type-Specific Roles of Human Odorant Receptors in Glioblastoma and the Tumor Microenvironment Author(s): Cho, Hee Jin; Yeo, Dong Jun; Yang, HeeWoong; Koo, JaeHyung Abstract: Odorant receptors (ORs), which constitute approximately 50% of all human G protein-coupled receptors, are increasingly recognized for their diverse roles beyond odor perception, including functions in various pathological conditions like brain diseases and cancers. However, the roles of ORs in glioblastoma (GBM), the most aggressive primary brain tumor with a median survival of only 15 months, remain largely unexplored. Here, we performed an integrated transcriptomic analysis combining The Cancer Genome Atlas RNA-seq and single-cell RNA sequencing data from GBM patients to uncover cell-type-specific roles of ORs within the tumor and its microenvironment. Our findings reveal that ORs display distinct expression patterns, with OR51E1 enriched in pericytes linked to vascular remodeling and angiogenesis, OR2B11 associated with tumor-associated macrophages supporting immunosuppressive phenotypes, and OR2L13 correlated with synaptic activity in recurrent tumors, potentially mediating treatment-induced neuronal adaptations. These results highlight ORs as potential therapeutic targets, offering new insights into their regulatory roles in GBM progression, immune modulation, and treatment resistance. © 2024 by the authors. Sat, 30 Nov 2024 15:00:00 GMT https://scholar.dgist.ac.kr/handle/20.500.11750/57468 2024-11-30T15:00:00Z