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Electron microscopy of human factor VIII/Von Willebrand glycoprotein: effect of reducing reagents on structure and function.

Publication ,  Journal Article
Ohmori, K; Fretto, LJ; Harrison, RL; Switzer, ME; Erickson, HP; McKee, PA
Published in: J Cell Biol
November 1982

The structure of native and progressively reduced human factor VIII/von Willebrand factor (FVIII/vWF) was examined by electron microscopy and SDS gel electrophoresis and then correlated with its biological activities. Highly resolved electron micrographs of well-spaced, rotary-shadowed FVIII/vWF molecules showed their structure to consist of a very flexible filament that contains irregularly spaced small nodules. Filaments ranged from 50 to 1,150 nm with a mean length of 478 nm and lacked fixed, large globular domains as seen in fibrinogen and IgM. A population of multimeric FVIII/vWF species ranging in molecular weight from 1 to 5 million daltons and differing in size alternately by one and two subunits was observed on SDS-2% polyacrylamide-0.5% agarose gel electrophoresis. With progressive reduction of disulfide bonds by dithiothreitol (DTT), the electron microscopic size of FVIII/vWF decreased in parallel with increased electrophoretic mobility on SDS-agarose gels; between 0.1 and 0.5 mM DTT its structure changed from predominantly fibrillar species to large nodular forms. A 50% loss of vWF specific activity and FVIII procoagulant activity occurred at 0.4 mM DTT and 1 mM DTT, respectively, corresponding to the reduction of 4 and 12 disulfide bonds of the 62 disulfides per 200,000-dalton subunit. We conclude that reduction of a few critical disulfide bonds results in a major structural change by electron microscopy and a concomitant loss of approximately 50% of the vWF function.

Duke Scholars

Published In

J Cell Biol

DOI

ISSN

0021-9525

Publication Date

November 1982

Volume

95

Issue

2 Pt 1

Start / End Page

632 / 640

Location

United States

Related Subject Headings

  • von Willebrand Factor
  • Structure-Activity Relationship
  • Ristocetin
  • Protein Conformation
  • Platelet Aggregation
  • Molecular Weight
  • Microscopy, Electron
  • Mercaptoethanol
  • Macromolecular Substances
  • Humans
 

Citation

APA
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ICMJE
MLA
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Ohmori, K., Fretto, L. J., Harrison, R. L., Switzer, M. E., Erickson, H. P., & McKee, P. A. (1982). Electron microscopy of human factor VIII/Von Willebrand glycoprotein: effect of reducing reagents on structure and function. J Cell Biol, 95(2 Pt 1), 632–640. https://doi.org/10.1083/jcb.95.2.632
Ohmori, K., L. J. Fretto, R. L. Harrison, M. E. Switzer, H. P. Erickson, and P. A. McKee. “Electron microscopy of human factor VIII/Von Willebrand glycoprotein: effect of reducing reagents on structure and function.J Cell Biol 95, no. 2 Pt 1 (November 1982): 632–40. https://doi.org/10.1083/jcb.95.2.632.
Ohmori K, Fretto LJ, Harrison RL, Switzer ME, Erickson HP, McKee PA. Electron microscopy of human factor VIII/Von Willebrand glycoprotein: effect of reducing reagents on structure and function. J Cell Biol. 1982 Nov;95(2 Pt 1):632–40.
Ohmori, K., et al. “Electron microscopy of human factor VIII/Von Willebrand glycoprotein: effect of reducing reagents on structure and function.J Cell Biol, vol. 95, no. 2 Pt 1, Nov. 1982, pp. 632–40. Pubmed, doi:10.1083/jcb.95.2.632.
Ohmori K, Fretto LJ, Harrison RL, Switzer ME, Erickson HP, McKee PA. Electron microscopy of human factor VIII/Von Willebrand glycoprotein: effect of reducing reagents on structure and function. J Cell Biol. 1982 Nov;95(2 Pt 1):632–640.

Published In

J Cell Biol

DOI

ISSN

0021-9525

Publication Date

November 1982

Volume

95

Issue

2 Pt 1

Start / End Page

632 / 640

Location

United States

Related Subject Headings

  • von Willebrand Factor
  • Structure-Activity Relationship
  • Ristocetin
  • Protein Conformation
  • Platelet Aggregation
  • Molecular Weight
  • Microscopy, Electron
  • Mercaptoethanol
  • Macromolecular Substances
  • Humans