Ligand-Specific Factors Influencing GLP-1 Receptor Post-Endocytic Trafficking and Degradation in Pancreatic Beta Cells

International Journal of Molecular Sciences

Alessia David¹  Johannes Broichhagen²  MariaM. Shchepinova³  EdwardW. Tate³  Frank Reimann⁴  DavidJ. Hodson⁵  IvanR. Corrêa Jr⁶  GuyA. Rutter⁷  Stavroula Bitsi⁷  Alejandra Tomas⁷  Yusman Manchanda⁷  StephenR. Bloom⁸  Ben Jones⁸  Shiqian Chen⁸  Victoria Salem⁸  Zijian Fang⁸  Tricia Tan⁸  Philip Pickford⁸ 

[1] Centre for Bioinformatics and System Biology, Department of Life Sciences, Imperial College London, London SW7 2BX, UK;Department of Chemical Biology, Leibniz-Forschungsinstitut für Molekulare Pharmakologie, 13125 Berlin, Germany;Department of Chemistry, Imperial College London, Molecular Sciences Research Hub, 80 Wood Lane, London W12 0BZ, UK;Institute of Metabolic Science & MRC Metabolic Diseases Unit, University of Cambridge, Addenbrooke’s Hospital, Hills Road, Cambridge CB2 0QQ, UK;Institute of Metabolism and Systems Research (IMSR), and Centre of Membrane Proteins and Receptors (COMPARE), University of Birmingham, Birmingham B15 2TT, UK;New England Biolabs, Ipswich, MA 01938, USA;Section of Cell Biology and Functional Genomics, Imperial College London, London W12 0NN, UK;Section of Endocrinology and Investigative Medicine, Imperial College London, London W12 0NN, UK;

关键词: glucagon-like peptide-1;    exendin-4;    trafficking;    biased agonism;    degradation;    endothelin converting enzyme-1;   

DOI  :  10.3390/ijms21218404

来源: DOAJ

【 摘 要 】

The glucagon-like peptide-1 receptor (GLP-1R) is an important regulator of blood glucose homeostasis. Ligand-specific differences in membrane trafficking of the GLP-1R influence its signalling properties and therapeutic potential in type 2 diabetes. Here, we have evaluated how different factors combine to control the post-endocytic trafficking of GLP-1R to recycling versus degradative pathways. Experiments were performed in primary islet cells, INS-1 832/3 clonal beta cells and HEK293 cells, using biorthogonal labelling of GLP-1R to determine its localisation and degradation after treatment with GLP-1, exendin-4 and several further GLP-1R agonist peptides. We also characterised the effect of a rare GLP1R coding variant, T149M, and the role of endosomal peptidase endothelin-converting enzyme-1 (ECE-1), in GLP1R trafficking. Our data reveal how treatment with GLP-1 versus exendin-4 is associated with preferential GLP-1R targeting towards a recycling pathway. GLP-1, but not exendin-4, is a substrate for ECE-1, and the resultant propensity to intra-endosomal degradation, in conjunction with differences in binding affinity, contributes to alterations in GLP-1R trafficking behaviours and degradation. The T149M GLP-1R variant shows reduced signalling and internalisation responses, which is likely to be due to disruption of the cytoplasmic region that couples to intracellular effectors. These observations provide insights into how ligand- and genotype-specific factors can influence GLP-1R trafficking.

【 授权许可】

Unknown