The binding in vitro of modified LDL to the intermediate filament protein vimentin

Biochem Biophys Res Commun. 2000 Jan 7;267(1):49-53. doi: 10.1006/bbrc.1999.1940.


Membrane-associated proteins with specific binding properties to modified LDL were investigated in J774 macrophages and Mono Mac 6 sr cells. Ligand blotting of membrane proteins revealed a 54-kDa protein which bound oxidized and acetylated but not native LDL. The 54-kDa protein, isolated by 2D-PAGE, was identified as vimentin. (125)I-AcLDL bound to purified vimentin and desmin in a saturable manner, with an approximate K(d) of 1.7 x 10(-7) M (89 microgram/ml) and 8.0 x 10(-8) M (41 microgram/ml), respectively. Blots of vimentin mutant proteins with deletions in the positively charged N-terminal head domain showed that amino acids 26-39 are essential for the binding of AcLDL by vimentin. Taken together, our data indicate that vimentin binds modified LDL, but not native LDL, in a specific and saturable manner. Vimentin filaments extend throughout the cytoplasm as far as the inner surfaces of plasma and vesicular membranes. Vimentin may thus play a role in membrane-associated steps involved in the intracellular processing of oxidized LDL, contributing to its unregulated uptake and intracellular retention by cells of the atherogenic plaque.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Cell Line
  • Cell Membrane / metabolism
  • Desmin / chemistry
  • Desmin / metabolism*
  • Humans
  • Iodine Radioisotopes
  • Kinetics
  • Lipoproteins, LDL / chemistry
  • Lipoproteins, LDL / isolation & purification
  • Lipoproteins, LDL / metabolism*
  • Macrophages / metabolism
  • Membrane Proteins / chemistry
  • Membrane Proteins / isolation & purification
  • Membrane Proteins / metabolism*
  • Mice
  • Molecular Sequence Data
  • Monocytes
  • Mutagenesis, Site-Directed
  • Peptide Fragments / chemistry
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Sequence Deletion
  • Vimentin / chemistry*
  • Vimentin / metabolism*


  • Desmin
  • Iodine Radioisotopes
  • Lipoproteins, LDL
  • Membrane Proteins
  • Peptide Fragments
  • Recombinant Proteins
  • Vimentin
  • acetyl-LDL