Dataset Information

Arrestin-independent constitutive endocytosis of GPR125/ADGRA3.

ABSTRACT: The orphan receptor GPR125 (ADGRA3) belongs to subgroup III of the adhesion G protein-coupled receptor (aGPCR) family. aGPCRs, also known as class B2 GPCRs, share basic structural and functional properties with other GPCRs. Many of them couple to G proteins and activate G protein-dependent and -independent signaling pathways, but little is known about aGPCR internalization and ?-arrestin recruitment. GPR125 was originally described as a spermatogonial stem cell marker and studied for its role in Wnt signaling and cell polarity. Here, using cell-based assays and confocal microscopy, we show that GPR125 is expressed on the cell surface and undergoes constitutive endocytosis in a ?-arrestin-independent, but clathrin-dependent manner, as indicated by colocalization with transferrin receptor 1, an early endosome marker. These data support that the constitutive internalization of GPR125 contributes to its biological functions by controlling receptor surface expression and accessibility for ligands. Our study sheds light on a new property of aGPCRs, namely internalization; a property described to be important for signal propagation, signal termination, and desensitization of class A (rhodopsin-like) and B1 (VIP/secretin) GPCRs.

SUBMITTER: Spiess K

PROVIDER: S-EPMC6899654 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Arrestin-independent constitutive endocytosis of GPR125/ADGRA3.

Spiess Katja K Bagger Sofie O SO Torz Lola J LJ Jensen Kristian H R KHR Walser Anna L AL Kvam Jone M JM Møgelmose Ann-Sofie K AK Daugvilaite Viktorija V Junnila Riia K RK Hjortø Gertrud M GM Rosenkilde Mette M MM

Annals of the New York Academy of Sciences 20191029 1

The orphan receptor GPR125 (ADGRA3) belongs to subgroup III of the adhesion G protein-coupled receptor (aGPCR) family. aGPCRs, also known as class B2 GPCRs, share basic structural and functional properties with other GPCRs. Many of them couple to G proteins and activate G protein-dependent and -independent signaling pathways, but little is known about aGPCR internalization and β-arrestin recruitment. GPR125 was originally described as a spermatogonial stem cell marker and studied for its role in ...[more]

PMID: 31659746

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Dataset Information

Arrestin-independent constitutive endocytosis of GPR125/ADGRA3.

Publications

Arrestin-independent constitutive endocytosis of GPR125/ADGRA3.

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