A six-armed oligomer isolated from cell surface fibronectin preparations.
Journal Article (Journal Article)
Fibronectins are adhesive glycoproteins thought to mediate the attachment of cells to various substrates. Plasma fibronectin (PFN) is a dimer comprising subunits of molecular weight 220,000, connected by one or two disulphide bonds. Electron microscopy shows that PFN is a long, flexible strand, 2-3 nm in diameter and 140 nm long. Many cells in tissue culture elaborate an extracellular matrix of insoluble (highly cross-linked by disulphide bonds) fibronectin, and a variable amount of 'cell surface fibronectin' (CSFN) that can be extracted by mild urea treatment. This CSFN, soluble in 1 M urea and at high pH, is a mixture of dimers and disulphide-bonded oligomers. In the present study we have examined the structure of these molecules by electron microscopy. Oligomers were separated from dimers and contaminating proteins by zone sedimentation through glycerol gradients. We report that the CSFN dimers are identical in structure to PFN. In contrast, the oligomers have an elaborate and well defined structure that we call a 'hexabrachion': six arms emanating from a central globular particle. The arms are similar to PFN in being long, thin and flexible, but have several distinctly different features.
Full Text
Duke Authors
Cited Authors
- Erickson, HP; Inglesias, JL
Published Date
- September 20, 1984
Published In
Volume / Issue
- 311 / 5983
Start / End Page
- 267 - 269
PubMed ID
- 6482952
International Standard Serial Number (ISSN)
- 0028-0836
Digital Object Identifier (DOI)
- 10.1038/311267a0
Language
- eng
Conference Location
- England