Adhesion GPCRs are structurally identified on the basis of a large extracellular region, similar to the Class B GPCR, but which is linked to the 7TM region by a GPCR autoproteolysis-inducing (GAIN) domain [1] containing a GPCR proteolytic site. The N-terminus often shares structural homology with adhesive domains (e.g. cadherins, immunolobulin, lectins) facilitating inter- and matricellular interactions and leading to the term adhesion GPCR [13,47]. Several receptors have been suggested to function as mechanosensors [6,30,33,44]. The nomenclature of these receptors was revised in 2015 as recommended by NC-IUPHAR and the Adhesion GPCR Consortium [15].

* Key recommended reading is highlighted with an asterisk

* Hamann J, Aust G, Araç D, Engel FB, Formstone C, Fredriksson R, Hall RA, Harty BL, Kirchhoff C, Knapp B et al.. (2015) International Union of Basic and Clinical Pharmacology. XCIV. Adhesion G protein-coupled receptors. Pharmacol. Rev., 67 (2): 338-67. [PMID:25713288]

* Langenhan T, Aust G, Hamann J. (2013) Sticky signaling--adhesion class G protein-coupled receptors take the stage. Sci Signal, 6 (276): re3. [PMID:23695165]

* Liebscher I, Schöneberg T. (2016) Tethered Agonism: A Common Activation Mechanism of Adhesion GPCRs. Handb Exp Pharmacol, 234: 111-125. [PMID:27832486]

* Monk KR, Hamann J, Langenhan T, Nijmeijer S, Schöneberg T, Liebscher I. (2015) Adhesion G Protein-Coupled Receptors: From In Vitro Pharmacology to In Vivo Mechanisms. Mol. Pharmacol., 88 (3): 617-23. [PMID:25956432]

* Purcell RH, Hall RA. (2018) Adhesion G Protein-Coupled Receptors as Drug Targets. Annu. Rev. Pharmacol. Toxicol., 58: 429-449. [PMID:28968187]

Yona S, Lin HH, Siu WO, Gordon S, Stacey M. (2008) Adhesion-GPCRs: emerging roles for novel receptors. Trends Biochem. Sci., 33 (10): 491-500. [PMID:18789697]

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Demet Arac-Ozkan Department of Biochemistry and Molecular Biology University of Chicago 929 E. 57th Street GCIS W210 Chicago, IL 60637 USA Gabriela Aust Department of Surgery University of Leipzig Liebigstr. 20 04103 Leipzig Germany Tom I. Bonner Special Volunteer Office of Science Director NIMH Bethesda MD USA Heike Cappallo-Obermann University Hospital Hamburg-Eppendorf Department of Andrology Martinistrasse 52 20246 Hamburg Germany Caroline Formstone MRC Centre for Developmental Neurobiology King's College London New Hunt's House, 4th Floor Guy's Hospital Campus London SE1 1UL UK Jörg Hamann Academic Medical Center University of Amsterdam Meibergdreef 9 1105AZ Amsterdam The Netherlands Breanne Harty Washington University School of Medicine Dept of Developmental Biology 660 S. Euclid Ave St. Louis MO 63130 USA Henrike Heyne Institute of Biochemistry Medical Faculty University of Leipzig Johannisallee 30 04103 Leipzig Germany Christiane Kirchhoff University Hospital Hamburg-Eppendorf Department of Andrology Martinistrasse 52 20246 Hamburg Germany Barbara Knapp Johannes-Gutenberg Universitaet Mainz Institut fuer Zoologie, Abt. I - AG Wolfrum Muellerweg 6 D-55099 Mainz Germany Arunkumar Krishnan Department of Neuroscience Biomedical Center Box 593 75 124 Uppsala Sweden Tobias Langenhan Division of General Biochemistry Rudolf-Schönheimer-Institute of Biochemistry University of Leipzig Johannisallee 3004103 Leipzig Germany Diana Le Duc Institute of Biochemistry Medical Faculty University of Leipzig Johannisallee 30 04103 Leipzig Germany Hsi-Hsien Lin Department of Microbiology and Immunology College of Medicine Chang Gung University 259 Wen-Hwa 1st Road Kwei-Shan Tao-Yuan Taiwan David C. Martinelli 265 Campus Drive Stanford California, 94305 USA Kelly Monk Washington University School of Medicine Dept of Developmental Biology 660 S. Euclid Ave St. Louis MO 63130 USA Xianhua Piao Boston Children's Hospital Department of Newborn Medicine 300 Longwood Avenue Boston MA 02115, USA Simone Prömel Institute of Biochemistry Medical Faculty University of Leipzig Johannisallee 30 04103 Leipzig Germany Helgi Schiöth Dept. of Neuroscience Biomedical Centre Uppsala University Uppsala Sweden Torsten Schöneberg Institute of Biochemistry Medical Faculty University of Leipzig Johannisallee 30 04103 Leipzig Germany Kathleen Singer Boston Children's Hospital Department of GI/Nutrition 300 Longwood Avenue Boston MA 02115, USA Martin Stacey Institute of Molecular and Cellular Biology Garstang 8.54 University of Leeds Leeds, LS2 9JT UK Yuri Ushkaryov Medway School of Pharmacy University of Kent Central Avenue Anson Building Chatham Maritime ME4 4TB UK Uwe Wolfrum Johannes-Gutenberg Universitaet Mainz Institut fuer Zoologie, Abt. I - AG Wolfrum Muellerweg 6 D-55099 Mainz Germany Lei Xu 601 Elmwood Ave. Department of Biomedical Genetics University of Rochester Medical Center Rochester NY 14642, USA