Abstract
We examined the pathway of prostaglandin E(2) (PGE(2))-induced internalization of the prostaglandin EP4 receptor in HEK 293 cells. Co-expression of dominant negative beta-arrestin (319-418) or dynamin I (K44A) with the EP4 receptor reduced internalization. The activated receptor co-localized with GFP-arrestin 2 and GFP-arrestin 3, confirming the requirement for beta-arrestins in internalization. Inhibition of clathrin-coated vesicle-mediated internalization resulted in inhibition of sequestration, whereas inhibition of caveola-mediated internalization had no effect. PGE(2) stimulation of the EP4 receptor resulted in rapid mitogen-activated protein (MAP) kinase activation. Examination of an internalization-resistant mutant and co-expression of mutant accessory proteins with EP4 revealed that MAP kinase activation proceeds independently of internalization.
Publication types
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Research Support, Non-U.S. Gov't
MeSH terms
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Acetic Acid / pharmacology
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Arrestins / pharmacology*
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Cells, Cultured
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Dynamin I
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Dynamins
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Endocytosis / drug effects*
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Enzyme Activation / drug effects
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GTP Phosphohydrolases / pharmacology*
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Green Fluorescent Proteins
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Humans
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Luminescent Proteins / metabolism
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Mitogen-Activated Protein Kinases / metabolism*
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Phosphoproteins / pharmacology
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Protein Structure, Tertiary
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Receptors, Prostaglandin E / agonists*
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Receptors, Prostaglandin E / metabolism
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Receptors, Prostaglandin E, EP4 Subtype
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Tetradecanoylphorbol Acetate / pharmacology
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beta-Arrestins
Substances
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Arrestins
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Luminescent Proteins
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PTGER4 protein, human
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Phosphoproteins
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Receptors, Prostaglandin E
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Receptors, Prostaglandin E, EP4 Subtype
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arrestin3
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beta-Arrestins
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Green Fluorescent Proteins
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Mitogen-Activated Protein Kinases
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Dynamin I
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GTP Phosphohydrolases
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Dynamins
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Tetradecanoylphorbol Acetate
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Acetic Acid