title: Phosphorylation of filamin A regulates chemokine receptor CCR2 recycling.
abstract: Proper endosomal trafficking of ligand-activated G-protein-coupled receptors (GPCRs) is essential to spatiotemporally tune their physiological responses. For the monocyte chemoattractant receptor 2 (CCR2B; one of two isoforms encoded by CCR2), endocytic recycling is important to sustain monocyte migration, whereas filamin A (FLNa) is essential for CCL2-induced monocyte migration. Here, we analyze the role of FLNa in the trafficking of CCR2B along the endocytic pathway. In FLNa-knockdown cells, activated CCR2B accumulated in enlarged EEA-1-positive endosomes, which exhibited slow movement and fast fluorescence recovery, suggesting an imbalance between receptor entry and exit rates. Utilizing super-resolution microscopy, we observed that FLNa-GFP, CCR2B and β2-adrenergic receptor (β2AR) were present in actin-enriched endosomal microdomains. Depletion of FLNa decreased CCR2B association with these microdomains and concomitantly delayed CCR2B endosomal traffic, without apparently affecting the number of microdomains. Interestingly, CCR2B and β2AR signaling induced phosphorylation of FLNa at residue S2152, and this phosphorylation event was contributes to sustain receptor recycling. Thus, our data strongly suggest that CCR2B and β2AR signals to FLNa to stimulate its endocytosis and recycling to the plasma membrane.
authors.affiliation: Department of Biology, Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain.
authors.forename: Mònica
authors.initials: M
authors.lastname: Pons
authors.affiliation: Department of Biology, Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain.
authors.forename: Ismael
authors.initials: I
authors.lastname: Izquierdo
authors.affiliation: Department of Biology, Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain.
authors.forename: Mireia
authors.initials: M
authors.lastname: Andreu-Carbó
authors.affiliation: Department of Biology, Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain.
authors.forename: Georgina
authors.initials: G
authors.lastname: Garrido
authors.affiliation: Department of Biomedicine, University of Bergen, Bergen, 5009 Norway.
authors.forename: Jesús
authors.initials: J
authors.lastname: Planagumà
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares, Madrid 28029, Spain.
authors.forename: Olivia
authors.initials: O
authors.lastname: Muriel
authors.affiliation: Centro Nacional de Investigaciones Cardiovasculares, Madrid 28029, Spain.
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Del Pozo
authors.affiliation: Department of Biology, Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain.
authors.forename: M Isabel
authors.initials: MI
authors.lastname: Geli
authors.affiliation: Department of Biology, Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain aarbmc@ibmb.csic.es.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Aragay
mesh_terms: D000199:Actins / Q000378:metabolism; D004705:Endocytosis; D011992:Endosomes / Q000378:metabolism; D064448:Filamins / Q000378:metabolism*; D055785:Gene Knockdown Techniques; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D021962:Membrane Microdomains / Q000378:metabolism; D008840:Microfilament Proteins / Q000378:metabolism; D008856:Microscopy, Fluorescence; D010766:Phosphorylation; D010768:Phosphoserine / Q000378:metabolism; D018343:Receptors, Adrenergic, beta-2 / Q000378:metabolism; D054390:Receptors, CCR2 / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D000199:Actins; D064448:Filamins; D008840:Microfilament Proteins; D018343:Receptors, Adrenergic, beta-2; D054390:Receptors, CCR2; C072061:coronin proteins; D010768:Phosphoserine
keywords: CCR2; Filamin A; GPCR; Recycling