Laminin E8 alveolarization site: heparin sensitivity, cell surface receptors, and role in cell spreading.
Cell adhesion to amino acids 2179-2198 (SN-peptide) of the laminin-1 alpha1-chain is required for lung alveolar formation in vitro (M. L. Matter and G. W. Laurie. J. Cell Biol. 124: 1083-1090, 1994). The nature of the SN-peptide receptor(s) was probed with neutralizing anti-integrin monoclonal antibodies (MAb), cells lacking integrin subunits, soluble heparin, and SN-peptide columns. Cell adhesion and spreading studies confirmed the specificity of SN-peptide and revealed adhesion to be unaffected by inclusion of anti-beta1-, anti-alpha(2-6)- or anti-alpha(V)beta5-integrin MAb. Cells lacking beta1- or alpha6-integrin subunits were fully adherent. Adhesion was heparin, but not chondroitin sulfate or heparinase, sensitive, much as is alpha-dystroglycan-laminin-1 binding. Heparin eluted approximately 155- and 180-kDa cell-surface proteins from SN-peptide columns. An additional approximately 91-kDa protein was eluted by EDTA. All were unrecognized by anti-beta1-integrin MAb. SN-peptide therefore interacts with three cell-surface proteins for which the identity remains to be determined.
Chen
L
L
Department of Cell Biology, University of Virginia, Charlottesville 22908, USA.
Shick
V
V
Matter
M L
ML
Laurie
S M
SM
Ogle
R C
RC
Laurie
G W
GW
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002413:Cations, Divalent; D002448:Cell Adhesion; D002809:Chondroitin Sulfates / Q000494:pharmacology; D002846:Chromatography, Affinity; D004492:Edetic Acid / Q000494:pharmacology; D006493:Heparin / Q000378:metabolism*; D019763:Heparin Lyase; D019012:Integrin beta1 / Q000378:metabolism; D007797:Laminin / Q000737:chemistry* / Q000502:physiology; D008024:Ligands; D051379:Mice; D008969:Molecular Sequence Data; D009024:Morphogenesis; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D011133:Polysaccharide-Lyases / Q000494:pharmacology; D011650:Pulmonary Alveoli / Q000254:growth & development*; D017474:Receptors, Laminin / Q000378:metabolism*
D002413:Cations, Divalent; D019012:Integrin beta1; D007797:Laminin; D008024:Ligands; D010455:Peptides; D017474:Receptors, Laminin; D006493:Heparin; D002809:Chondroitin Sulfates; D004492:Edetic Acid; D011133:Polysaccharide-Lyases; D019763:Heparin Lyase