Prolonged signaling of backbone- modified glucagon-like peptide-1 analogues with diverse receptor trafficking

• 成果类型: Article
• 署名作者: Cary, Brian P.; Hager, Marlies V.; Mariam, Zamara; Morris, Rylie K.; Belousoff, Matthew J.; Deganutti, Giuseppe; Sexton, Patrick M.; Wootten, Denise; Gellman, Samuel H.
• 署名单位: University of Wisconsin System; University of Wisconsin Madison; Monash University; Monash University; Coventry University
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-10362
• DOI: 10.1073/pnas.2407574122
• 发表日期: 2025-04-08
• 关键词: protein-coupled receptors; cryo-em structure; glp-1 receptor; insulin-secretion; adrenergic-receptor; thermodynamic scale; beta-arrestins; agonist; desensitization; camp

摘要

Signal duration and subcellular location are emerging as important facets of G protein-coupled receptor (GPCR) function. The glucagon-like peptide-1 receptor (GLP-1R), a clinically relevant class B1 GPCR, stimulates production of the second messenger cyclic adenosine monophosphate (cAMP) upon activation by the native hormone, GLP-1. cAMP production continues after the hormone-receptor complex has been internalized via endocytosis. Here, we report GLP-1 analogues that induce prolonged signaling relative to GLP-1. A single beta-amino acid substitution at position 18, with the residue derived from (S,S)- trans-2-aminocyclopentanecarboxylic acid (ACPC), enhances signaling duration with retention of receptor endocytosis. Pairing ACPC at position 18 with a second substitution, alpha- aminoisobutyric acid (Aib) at position 16, abrogates endocytosis, but prolonged signaling is maintained. Prolonged signaling is sensitive to the structure of the beta residue at position 18. Cryoelectron microscopy structures of two GLP-1 analogues bound to the GLP-1R:Gs complex suggest substantial alterations to bound peptide structure and dynamics compared to the GLP-1:GLP-1R:Gs complex. These structural findings strengthen an emerging view that agonist dynamics in the receptor-bound state influence signaling profiles. Our results advance understanding of the structural underpinnings of receptor activation and introduce tools for exploring the impact of spatiotemporal signaling profiles following GLP-1R activation.