16-kilodalton heparin binding (fibroblast) growth factor type one appears in a stable 40-kilodalton complex after receptor-dependent internalization

J Biol Chem. 1991 Mar 25;266(9):5774-9.


Incubation of 16-kDa 125I-labeled heparin binding (acidic fibroblast) growth factor type one (HBGF-1) with human hepatoma cells and normal rat hepatocytes resulted in the appearance of a stable 125I-labeled complex with an apparent molecular mass of 40 kDa. The complex could be isolated with specific antibodies against HBGF-1. In contrast to membrane receptor-bound 125I-HBGF-1, the complex was resistant to dissociation by detergents, acid, heat, and reducing or denaturing agents. Formation of a stable complex did not require treatment with cross-linking agents. Appearance of the 40-kDa complex was dependent on time, temperature, and enriched culture medium. Conditions that enhanced or reduced display of specific HBGF-1 membrane receptor sites enhanced or reduced the appearance of the 40-kDa complex. Dansylcadaverine, chloroquine, and staurosporine blocked the appearance of the 40-kDa complex concurrent with the blockage of internalization of the receptor-bound HBGF-1. Two-dimensional gel electrophoretic analysis, metabolic labeling with L-[35S]cysteine, and recovery of 16-kDa HBGF-1 from the 40-kDa complex after base treatment suggest involvement of a 24-kDa cellular protein in the complex formation. These results suggest a potentially novel receptor-dependent pathway for metabolism of HBGF-1.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alkaloids / pharmacology
  • Animals
  • Biotin / chemistry
  • Cadaverine / analogs & derivatives
  • Cadaverine / pharmacology
  • Chloroquine / pharmacology
  • Cross-Linking Reagents
  • Electrophoresis, Gel, Two-Dimensional
  • Electrophoresis, Polyacrylamide Gel
  • Fibroblast Growth Factors / metabolism*
  • Heparin / metabolism*
  • Humans
  • Liver / metabolism
  • Molecular Weight
  • Precipitin Tests
  • Rats
  • Staurosporine
  • Temperature
  • Tumor Cells, Cultured


  • Alkaloids
  • Cross-Linking Reagents
  • Fibroblast Growth Factors
  • Biotin
  • Chloroquine
  • Heparin
  • Staurosporine
  • monodansylcadaverine
  • Cadaverine