National Health and Medical Research Council (NHMRC, Australia)
2021675
オーストラリア
National Health and Medical Research Council (NHMRC, Australia)
1196951
オーストラリア
引用
ジャーナル: bioRxiv / 年: 2025 タイトル: Structure-guided allosteric modulation of the delta opioid receptor. 著者: Jesse I Mobbs / M Deborah Nguyen / Owindeep Deo / Damian Bartuzi / Hariprasad Venugopal / Sadia Alvi / Vi Pham / Nick Barnes / Arthur Christopoulos / Daniel P Poole / Simona E Carbone / ...著者: Jesse I Mobbs / M Deborah Nguyen / Owindeep Deo / Damian Bartuzi / Hariprasad Venugopal / Sadia Alvi / Vi Pham / Nick Barnes / Arthur Christopoulos / Daniel P Poole / Simona E Carbone / Manuela Jörg / Ben Capuano / Jens Carlsson / Arisbel B Gondin / Peter J Scammells / Celine Valant / David M Thal / 要旨: Opioid analgesics remain essential for pain management but are associated with significant adverse effects, including respiratory depression, tolerance, and dependence. The δ-opioid receptor (δOR) ...Opioid analgesics remain essential for pain management but are associated with significant adverse effects, including respiratory depression, tolerance, and dependence. The δ-opioid receptor (δOR) represents a promising therapeutic target for developing safer opioid analgesics with reduced adverse effects compared to conventional μ-opioid receptor-targeting drugs. Positive allosteric modulators (PAMs) offer advantages over direct agonists by enhancing endogenous opioid signaling while preserving natural spatiotemporal activation patterns, potentially avoiding tolerance and dependence issues. Here, we present high-resolution cryo-EM structures of δOR complexed with the peptide agonist DADLE and the PAM MIPS3614, revealing a novel lipid-facing allosteric binding site formed by transmembrane helices 2, 3, and 4. MIPS3614 stabilizes the active receptor conformation through a critical hydrogen bond with residue N131 in the conserved sodium binding site, a key regulatory region controlling GPCR activation. Comprehensive mutagenesis, molecular dynamics simulations, and structure-activity relationships validate this proposed mechanism. Structure-guided optimization yielded MIPS3983 with enhanced binding affinity and retained cooperativity. Our findings establish the first molecular framework for δOR allosteric modulation and provide a structural foundation for the rational design of safer opioid therapeutics.