title: The Viral G Protein-Coupled Receptor ORF74 Hijacks β-Arrestins for Endocytic Trafficking in Response to Human Chemokines.
abstract: Kaposi's sarcoma-associated herpesvirus-infected cells express the virally encoded G protein-coupled receptor ORF74. Although ORF74 is constitutively active, it binds human CXC chemokines that modulate this basal activity. ORF74-induced signaling has been demonstrated to underlie the development of the angioproliferative tumor Kaposi's sarcoma. Whereas G protein-dependent signaling of ORF74 has been the subject of several studies, the interaction of this viral GPCR with β-arrestins has hitherto not been investigated. Bioluminescence resonance energy transfer experiments demonstrate that ORF74 recruits β-arrestins and subsequently internalizes in response to human CXCL1 and CXCL8, but not CXCL10. Internalized ORF74 traffics via early endosomes to recycling and late endosomes. Site-directed mutagenesis and homology modeling identified four serine and threonine residues at the distal end of the intracellular carboxyl-terminal of ORF74 that are required for β-arrestin recruitment and subsequent endocytic trafficking. Hijacking of the human endocytic trafficking machinery is a previously unrecognized action of ORF74.
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Sabrina M
authors.initials: SM
authors.lastname: de Munnik
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Albert J
authors.initials: AJ
authors.lastname: Kooistra
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Jody
authors.initials: J
authors.lastname: van Offenbeek
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Saskia
authors.initials: S
authors.lastname: Nijmeijer
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Chris
authors.initials: C
authors.lastname: de Graaf
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Martine J
authors.initials: MJ
authors.lastname: Smit
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Rob
authors.initials: R
authors.lastname: Leurs
authors.affiliation: Department of Chemistry and Pharmaceutical Sciences, Division of Medicinal Chemistry, Amsterdam Institute for Molecules, Medicines and Systems (AIMMS), VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Henry F
authors.initials: HF
authors.lastname: Vischer
mesh_terms: D000595:Amino Acid Sequence; D019390:Arrestins / Q000378:metabolism*; D049109:Cell Proliferation; D054360:Chemokine CXCL1 / Q000378:metabolism*; D054357:Chemokine CXCL10 / Q000378:metabolism*; D018076:DNA, Complementary / Q000378:metabolism; D004705:Endocytosis; D004797:Enzyme-Linked Immunosorbent Assay; D057809:HEK293 Cells; D006801:Humans; D016209:Interleukin-8 / Q000378:metabolism*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D017433:Protein Structure, Secondary; D019707:Receptors, Chemokine / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D012694:Serine / Q000737:chemistry; D015398:Signal Transduction; D013912:Threonine / Q000737:chemistry; D010738:Type C Phospholipases / Q000378:metabolism; D014764:Viral Proteins / Q000378:metabolism*; D000071557:beta-Arrestins
chemical_list: D019390:Arrestins; C475829:CXCL1 protein, human; C114753:CXCL10 protein, human; C508606:CXCL8 protein, human; D054360:Chemokine CXCL1; D054357:Chemokine CXCL10; D018076:DNA, Complementary; D016209:Interleukin-8; C105181:ORF74 protein, Human herpesvirus 8; D019707:Receptors, Chemokine; D043562:Receptors, G-Protein-Coupled; D014764:Viral Proteins; D000071557:beta-Arrestins; D013912:Threonine; D012694:Serine; D010738:Type C Phospholipases