Visualization of purified fibronectin-transglutaminase complexes.

Published

Journal Article

It has been reported previously (Turner, P.M., and Lorand, L. (1989) Biochemistry 28, 628-635) that human erythrocyte transglutaminase forms a noncovalent complex with human plasma fibronectin near its collagen-binding domain. In the present study, we show by nondenaturing electrophoresis that guinea pig liver transglutaminase, similarly to the erythrocyte enzyme, forms a complex with human fibronectin. Studies of anisotropic shifts of fluorescein-labeled liver and erythrocyte transglutaminases, upon addition of fibronectin, indicated that both transglutaminases bind to fibronectin with a stoichiometry of about 2:1. Polymerization of fibrinogen by human erythrocyte transglutaminase was inhibited after complex formation with fibronectin. Complexes of fibronectin with either erythrocyte or liver transglutaminase were isolated by glycerol gradient zone sedimentation and examined by rotary shadowing electron microscopy. The globular transglutaminase could be readily identified binding to the thin fibronectin strand. The binding site for transglutaminase was within 5-10 nm of the N terminus of fibronectin, consistent with its proximity to the collagen-binding domain. Under some experimental conditions, the complex of fibronectin with erythrocyte transglutaminase appeared as a ring-shaped structure in which two transglutaminase molecules had probably dimerized. The molecular weight of the erythrocyte transglutaminase was determined by sedimentation equilibrium to be 71,440 +/- 830.

Full Text

Duke Authors

Cited Authors

  • LeMosy, EK; Erickson, HP; Beyer, WF; Radek, JT; Jeong, JM; Murthy, SN; Lorand, L

Published Date

  • April 15, 1992

Published In

Volume / Issue

  • 267 / 11

Start / End Page

  • 7880 - 7885

PubMed ID

  • 1348509

Pubmed Central ID

  • 1348509

International Standard Serial Number (ISSN)

  • 0021-9258

Language

  • eng

Conference Location

  • United States