title: Src regulates sequence-dependent beta-2 adrenergic receptor recycling via cortactin phosphorylation.
abstract: The recycling of internalized signaling receptors, which has direct functional consequences, is subject to multiple sequence and biochemical requirements. Why signaling receptors recycle via a specialized pathway, unlike many other proteins that recycle by bulk, is a fundamental unanswered question. Here, we show that these specialized pathways allow selective control of signaling receptor recycling by heterologous signaling. Using assays to visualize receptor recycling in living cells, we show that the recycling of the beta-2 adrenergic receptor (B2AR), a prototypic signaling receptor, is regulated by Src family kinases. The target of Src is cortactin, an essential factor for B2AR sorting into specialized recycling microdomains on the endosome. Phosphorylation of a single cortactin residue, Y466, regulates the rate of fission of B2AR recycling vesicles from these microdomains and, therefore, the rate of delivery of B2AR to the cell surface. Together, our results indicate that actin-stabilized microdomains that mediate signaling receptor recycling can serve as a functional point of convergence for crosstalk between signaling pathways.
authors: Department of Biological Sciences, The Center for the Neural Basis of Cognition, Carnegie Mellon University, MI202, 4400 Fifth Avenue, Pittsburgh, PA, 15213, USA.
authors: Rachel
authors: R
authors: Vistein
authors: Manojkumar A
authors: MA
authors: Puthenveedu
mesh_terms: D051356:Cortactin / Q000378:metabolism*; D011992:Endosomes / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D021381:Protein Transport; D018343:Receptors, Adrenergic, beta-2 / Q000378:metabolism*; D015398:Signal Transduction; D019061:src-Family Kinases / Q000378:metabolism*
chemical_list: D051356:Cortactin; D018343:Receptors, Adrenergic, beta-2; D019061:src-Family Kinases
keywords: GPCR; Src; actin cytoskeleton; cortactin; crosstalk; endosome; heterologous regulation; regulated recycling; sequence-dependent recycling; trafficking; tubules; vesicle scission