title: Heparin interacts with the adhesion GPCR GPR56, reduces receptor shedding, and promotes cell adhesion and motility.
abstract: GPR56 is an adhesion-class G-protein-coupled receptor responsible for bilateral frontoparietal polymicrogyria (BFPP), a severe disorder of cortical formation. Additionally, GPR56 is involved in biological processes as diverse as hematopoietic stem cell generation and maintenance, myoblast fusion, muscle hypertrophy, immunoregulation and tumorigenesis. Collagen III and tissue transglutaminase 2 (TG2) have been revealed as the matricellular ligands of GPR56 involved in BFPP and melanoma development, respectively. In this study, we identify heparin as a glycosaminoglycan interacting partner of GPR56. Analyses of truncated and mutant GPR56 proteins reveal two basic-residue-rich clusters, R(26)GHREDFRFC(35) and L(190)KHPQKASRRP(200), as the major heparin-interacting motifs that overlap partially with the collagen III- and TG2-binding sites. Interestingly, the GPR56-heparin interaction is modulated by collagen III but not TG2, even though both ligands are also heparin-binding proteins. Finally, we show that the interaction with heparin reduces GPR56 receptor shedding, and enhances cell adhesion and motility. These results provide novel insights into the interaction of GPR56 with its multiple endogenous ligands and have functional implications in diseases such as BFPP and cancer.
authors.affiliation: Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan.
authors.forename: Nien-Yi
authors.identifier: 0000-0002-9918-8079
authors.initials: NY
authors.lastname: Chiang
authors.affiliation: Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan.
authors.forename: Gin-Wen
authors.identifier: 0000-0002-6509-6897
authors.initials: GW
authors.lastname: Chang
authors.affiliation: Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan.
authors.forename: Yi-Shu
authors.identifier: 0000-0001-8770-9298
authors.initials: YS
authors.lastname: Huang
authors.affiliation: Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan.
authors.forename: Yen-Ming
authors.initials: YM
authors.lastname: Peng
authors.affiliation: Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan.
authors.forename: Cheng-Chih
authors.initials: CC
authors.lastname: Hsiao
authors.affiliation: Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan Chang Gung Immunology Consortium, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan 333, Taiwan Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital-Linkou, Tao-Yuan 333, Taiwan.
authors.forename: Ming-Ling
authors.initials: ML
authors.lastname: Kuo
authors.affiliation: Department of Microbiology and Immunology, Chang Gung University, Tao-Yuan 333, Taiwan Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan Chang Gung Immunology Consortium, Chang Gung Memorial Hospital and Chang Gung University, Tao-Yuan 333, Taiwan Department of Anatomic Pathology, Chang Gung Memorial Hospital-Linkou, Tao-Yuan 333, Taiwan hhlin@mail.cgu.edu.tw.
authors.forename: Hsi-Hsien
authors.identifier: 0000-0003-0679-5222
authors.initials: HH
authors.lastname: Lin
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D002448:Cell Adhesion; D045744:Cell Line, Tumor; D002465:Cell Movement; D057809:HEK293 Cells; D006493:Heparin / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008024:Ligands; D021962:Membrane Microdomains / Q000378:metabolism; D009361:Neoplasm Invasiveness; D011485:Protein Binding; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D025941:Protein Interaction Mapping; D051571:Protein Kinase C-alpha / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000737:chemistry / Q000378:metabolism*; D020742:rhoA GTP-Binding Protein / Q000378:metabolism
chemical_list: D008024:Ligands; D043562:Receptors, G-Protein-Coupled; C000717608:TGM2 protein, human; D006493:Heparin; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D051571:Protein Kinase C-alpha; D020742:rhoA GTP-Binding Protein
keywords: Adhesion; GPCR; GPR56; Glycosaminoglycan; Heparin; Shedding