Vps37a regulates hepatic glucose production by controlling glucagon receptor localization to endosomes

authored by
Revathi Sekar, Karsten Motzler, Yun Kwon, Aaron Novikoff, Julia Jülg, Bahar Najafi, Surui Wang, Anna Luisa Warnke, Susanne Seitz, Daniela Hass, Sofiya Gancheva, Sabine Kahl, Bin Yang, Brian Finan, Kathrin Schwarz, Juergen G. Okun, Michael Roden, Matthias Blüher, Timo D. Müller, Natalie Krahmer, Christian Behrends, Oliver Plettenburg, Marta Miaczynska, Stephan Herzig, Anja Zeigerer
Abstract

During mammalian energy homeostasis, the glucagon receptor (Gcgr) plays a key role in regulating both glucose and lipid metabolisms. However, the mechanisms by which these distinct signaling arms are differentially regulated remain poorly understood. Using a Cy5-glucagon agonist, we show that the endosomal protein Vps37a uncouples glucose production from lipid usage downstream of Gcgr signaling by altering intracellular receptor localization. Hepatocyte-specific knockdown of Vps37a causes an accumulation of Gcgr in endosomes, resulting in overactivation of the cAMP/PKA/p-Creb signaling pathway to gluconeogenesis without affecting β-oxidation. Shifting the receptor back to the plasma membrane rescues the differential signaling and highlights the importance of the spatiotemporal localization of Gcgr for its metabolic effects. Importantly, since Vps37a knockdown in animals fed with a high-fat diet leads to hyperglycemia, although its overexpression reduces blood glucose levels, these data reveal a contribution of endosomal signaling to metabolic diseases that could be exploited for treatments of type 2 diabetes.

Organisation(s)
Institute of Organic Chemistry
External Organisation(s)
German Center for Diabetes Research (DZD)
Ludwig-Maximilians-Universität München (LMU)
University Hospital Düsseldorf
Novo Nordisk AS
Leipzig University
International Institute of Molecular and Cell Biology
Technical University of Munich (TUM)
Universitätsklinikum Heidelberg
Helmholtz Zentrum München - German Research Center for Environmental Health
Type
Article
Journal
Cell metabolism
Volume
34
Pages
1824-1842.e9
ISSN
1550-4131
Publication date
01.11.2022
Publication status
Published
Peer reviewed
Yes
ASJC Scopus subject areas
Physiology, Molecular Biology, Cell Biology
Sustainable Development Goals
SDG 3 - Good Health and Well-being
Electronic version(s)
https://doi.org/10.1016/j.cmet.2022.09.022 (Access: Open)
https://doi.org/10.1016/j.cmet.2022.10.013 (Access: Open)