title: The binding of fibronectin to entactin is mediated through the 29 kDa amino terminal fragment of fibronectin and the G2 domain of entactin.
abstract: Previous work has shown that fibronectin and entactin, an ubiquitous basement membrane glycoprotein, co-localize in the extracellular matrix of the embryonal carcinoma-derived 4CQ cell. Glutathione-S-transferase (GST) fusion proteins containing different domains of entactin have been obtained in the pGEX3X expression vector. These fusion proteins, GST-G1, GST-G2, GST-E and GST-G3, were purified with a glutathione affinity column. By using a solid phase binding assay, it was shown that the 125I-labeled 29 kDa amino terminal fragment of bovine fibronectin bound specifically to the immobilized GST-G2 fusion protein but not to GST-G1, GST-E, and GST-G3. Half saturation for binding of the 29 kDa fibronectin fragment to the immobilized GST-G2 fusion protein was obtained at a concentration of approximately 5 nM. It is suggested that the strong association between GST-G2, which contains the second globular domain of entactin, and the 29 kDa amino terminal fragment of fibronectin may be involved in the assembly of certain types of extracellular matrices.
authors.affiliation: Department of Biological Sciences, University of Pittsburgh, PA 15260.
authors.forename: J C
authors.initials: JC
authors.lastname: Hsieh
authors.forename: C
authors.initials: C
authors.lastname: Wu
authors.forename: A E
authors.initials: AE
authors.lastname: Chung
mesh_terms: D000818:Animals; D001485:Basement Membrane / Q000378:metabolism; D002417:Cattle; D003001:Cloning, Molecular / Q000379:methods; D004800:Enzymes, Immobilized / Q000378:metabolism; D005353:Fibronectins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D005822:Genetic Vectors; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008562:Membrane Glycoproteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D017433:Protein Structure, Secondary; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D015183:Restriction Mapping
chemical_list: D004800:Enzymes, Immobilized; D005353:Fibronectins; D008562:Membrane Glycoproteins; D010446:Peptide Fragments; D011993:Recombinant Fusion Proteins; D011994:Recombinant Proteins; C029967:nidogen; D005982:Glutathione Transferase