Cookies on this website

We use cookies to ensure that we give you the best experience on our website. If you click 'Accept all cookies' we'll assume that you are happy to receive all cookies and you won't see this message again. If you click 'Reject all non-essential cookies' only necessary cookies providing core functionality such as security, network management, and accessibility will be enabled. Click 'Find out more' for information on how to change your cookie settings.

Adaptor protein-2 (AP2), a central component of clathrin-coated vesicles (CCVs), is pivotal in clathrin-mediated endocytosis, which internalizes plasma membrane constituents such as G protein-coupled receptors (GPCRs). AP2, a heterotetramer of α, β, μ and σ subunits, links clathrin to vesicle membranes and binds to tyrosine- and dileucine-based motifs of membrane-associated cargo proteins. Here we show that missense mutations of AP2 σ subunit (AP2S1) affecting Arg15, which forms key contacts with dileucine-based motifs of CCV cargo proteins, result in familial hypocalciuric hypercalcemia type 3 (FHH3), an extracellular calcium homeostasis disorder affecting the parathyroids, kidneys and bone. We found AP2S1 mutations in >20% of cases of FHH without mutations in calcium-sensing GPCR (CASR), which cause FHH1. AP2S1 mutations decreased the sensitivity of CaSR-expressing cells to extracellular calcium and reduced CaSR endocytosis, probably through loss of interaction with a C-terminal CaSR dileucine-based motif, whose disruption also decreased intracellular signaling. Thus, our results identify a new role for AP2 in extracellular calcium homeostasis. © 2013 Nature America, Inc. All rights reserved.

Original publication

DOI

10.1038/ng.2492

Type

Journal article

Journal

Nature Genetics

Publication Date

01/01/2013

Volume

45

Pages

93 - 97