1
|
Pirona L, Ballabio F, Alfonso-Prieto M, Capelli R. Calcium-Driven In Silico Inactivation of a Human Olfactory Receptor. J Chem Inf Model 2024; 64:2971-2978. [PMID: 38523266 DOI: 10.1021/acs.jcim.4c00249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Conformational changes as well as molecular determinants related to the activation and inactivation of olfactory receptors are still poorly understood due to the intrinsic difficulties in the structural determination of this GPCR family. Here, we perform, for the first time, the in silico inactivation of human olfactory receptor OR51E2, highlighting the possible role of calcium in this receptor state transition. Using molecular dynamics simulations, we show that a divalent ion in the ion binding site, coordinated by two acidic residues at positions 2.50 and 3.39 conserved across most ORs, stabilizes the receptor in its inactive state. In contrast, protonation of the same two acidic residues is not sufficient to drive inactivation within the microsecond timescale of our simulations. Our findings suggest a novel molecular mechanism for OR inactivation, potentially guiding experimental validation and offering insights into the possible broader role of divalent ions in GPCR signaling.
Collapse
Affiliation(s)
- Lorenza Pirona
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, I-20133 Milano, Italy
| | - Federico Ballabio
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, I-20133 Milano, Italy
| | - Mercedes Alfonso-Prieto
- Computational Biomedicine, Institute for Neuroscience and Medicine INM-9, Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Straße, D-54248 Jülich, Germany
| | - Riccardo Capelli
- Department of Biosciences, Università degli Studi di Milano, Via Celoria 26, I-20133 Milano, Italy
| |
Collapse
|
2
|
Wu C, Xu M, Dong J, Cui W, Yuan S. The structure and function of olfactory receptors. Trends Pharmacol Sci 2024; 45:268-280. [PMID: 38296675 DOI: 10.1016/j.tips.2024.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 01/08/2024] [Accepted: 01/09/2024] [Indexed: 02/02/2024]
Abstract
Olfactory receptors (ORs) form the most important chemosensory receptor family responsible for our sense of smell in the nasal olfactory epithelium. This receptor family belongs to the class A G protein-coupled receptors (GPCRs). Recent research has indicated that ORs are involved in many nonolfactory physiological processes in extranasal tissue, such as the brain, pancreas, and testes, and implies the possible role of their dysregulation in various diseases. The recently released structures of OR51E2 and consensus OR52 have also unveiled the uniqueness of ORs from other class A GPCR members. In this review, we discuss these recent developments and computational modeling efforts toward understanding the structural properties of unresolved ORs, which could guide potential future OR-targeted drug discovery.
Collapse
Affiliation(s)
- Chenyang Wu
- The AlphaMol-SIAT Joint Laboratory, Shenzhen 518055, China; The Research Center for Computer-aided Drug Discovery, The Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Marc Xu
- The AlphaMol-SIAT Joint Laboratory, Shenzhen 518055, China; The Research Center for Computer-aided Drug Discovery, The Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Junlin Dong
- The AlphaMol-SIAT Joint Laboratory, Shenzhen 518055, China; The Research Center for Computer-aided Drug Discovery, The Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wenqiang Cui
- The AlphaMol-SIAT Joint Laboratory, Shenzhen 518055, China
| | - Shuguang Yuan
- The AlphaMol-SIAT Joint Laboratory, Shenzhen 518055, China; AlphaMol Science Ltd, Shenzhen 518055, China.
| |
Collapse
|
3
|
Billesbølle CB, de March CA, van der Velden WJC, Ma N, Tewari J, Del Torrent CL, Li L, Faust B, Vaidehi N, Matsunami H, Manglik A. Structural basis of odorant recognition by a human odorant receptor. Nature 2023; 615:742-749. [PMID: 36922591 PMCID: PMC10580732 DOI: 10.1038/s41586-023-05798-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Accepted: 02/06/2023] [Indexed: 03/17/2023]
Abstract
Our sense of smell enables us to navigate a vast space of chemically diverse odour molecules. This task is accomplished by the combinatorial activation of approximately 400 odorant G protein-coupled receptors encoded in the human genome1-3. How odorants are recognized by odorant receptors remains unclear. Here we provide mechanistic insight into how an odorant binds to a human odorant receptor. Using cryo-electron microscopy, we determined the structure of the active human odorant receptor OR51E2 bound to the fatty acid propionate. Propionate is bound within an occluded pocket in OR51E2 and makes specific contacts critical to receptor activation. Mutation of the odorant-binding pocket in OR51E2 alters the recognition spectrum for fatty acids of varying chain length, suggesting that odorant selectivity is controlled by tight packing interactions between an odorant and an odorant receptor. Molecular dynamics simulations demonstrate that propionate-induced conformational changes in extracellular loop 3 activate OR51E2. Together, our studies provide a high-resolution view of chemical recognition of an odorant by a vertebrate odorant receptor, providing insight into how this large family of G protein-coupled receptors enables our olfactory sense.
Collapse
Affiliation(s)
| | - Claire A de March
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
- Institut de Chimie des Substances Naturelles, UPR2301 CNRS, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Wijnand J C van der Velden
- Department of Computational and Quantitative Medicine, Beckman Research Institute of the City of Hope, Duarte, CA, USA
| | - Ning Ma
- Department of Computational and Quantitative Medicine, Beckman Research Institute of the City of Hope, Duarte, CA, USA
| | - Jeevan Tewari
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA
| | - Claudia Llinas Del Torrent
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
- Laboratory of Computational Medicine, Biostatistics Unit, Faculty of Medicine, Universitat Autònoma Barcelona, Bellaterra, Barcelona, Spain
| | - Linus Li
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Bryan Faust
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
| | - Nagarajan Vaidehi
- Department of Computational and Quantitative Medicine, Beckman Research Institute of the City of Hope, Duarte, CA, USA.
| | - Hiroaki Matsunami
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, USA.
- Department of Neurobiology, Duke Institute for Brain Sciences, Duke University, Durham, NC, USA.
| | - Aashish Manglik
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA.
- Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, USA.
| |
Collapse
|