title: Transmembrane and extracellular domains of syndecan-1 have distinct functions in regulating lung epithelial migration and adhesion.
abstract: Syndecan-1 is a cell surface proteoglycan that can organize co-receptors into a multimeric complex to transduce intracellular signals. The syndecan-1 core protein has multiple domains that confer distinct cell- and tissue-specific functions. Indeed, the extracellular, transmembrane, and cytoplasmic domains have all been found to regulate specific cellular processes. Our previous work demonstrated that syndecan-1 controls lung epithelial migration and adhesion. Here, we identified the necessary domains of the syndecan-1 core protein that modulate its function in lung epithelial repair. We found that the syndecan-1 transmembrane domain has a regulatory function in controlling focal adhesion disassembly, which in turn controls cell migration speed. In contrast, the extracellular domain facilitates cell adhesion through affinity modulation of α(2)β(1) integrin. These findings highlight the fact that syndecan-1 is a multidimensional cell surface receptor that has several regulatory domains to control various biological processes. In particular, the lung epithelium requires the syndecan-1 transmembrane domain to govern cell migration and is independent from its ability to control cell adhesion via the extracellular domain.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Center for Lung Biology, University of Washington, Seattle, Washington 98109-4752.
authors.forename: William A
authors.initials: WA
authors.lastname: Altemeier
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Center for Lung Biology, University of Washington, Seattle, Washington 98109-4752.
authors.forename: Saundra Y
authors.initials: SY
authors.lastname: Schlesinger
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Center for Lung Biology, University of Washington, Seattle, Washington 98109-4752.
authors.forename: Catherine A
authors.initials: CA
authors.lastname: Buell
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Center for Lung Biology, University of Washington, Seattle, Washington 98109-4752.
authors.forename: Rena
authors.initials: R
authors.lastname: Brauer
authors.affiliation: Department of Human Oncology, University of Wisconsin-Madison, Madison, Wisconsin 53792.
authors.forename: Alan C
authors.initials: AC
authors.lastname: Rapraeger
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Center for Lung Biology, University of Washington, Seattle, Washington 98109-4752.
authors.forename: William C
authors.initials: WC
authors.lastname: Parks
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Center for Lung Biology, University of Washington, Seattle, Washington 98109-4752. Electronic address: petechen@uw.edu.
authors.forename: Peter
authors.initials: P
authors.lastname: Chen
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D002461:Cell Line, Transformed; D002465:Cell Movement / Q000502:physiology*; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism*; D022001:Focal Adhesions / Q000235:genetics / Q000378:metabolism; D006801:Humans; D038982:Integrin alpha2beta1 / Q000235:genetics / Q000378:metabolism; D051379:Mice; D017434:Protein Structure, Tertiary; D020545:Respiratory Mucosa / Q000166:cytology / Q000378:metabolism*; D053668:Syndecan-1 / Q000235:genetics / Q000378:metabolism*
chemical_list: D038982:Integrin alpha2beta1; C508241:SDC1 protein, human; C508242:Sdc1 protein, mouse; D053668:Syndecan-1