Binding of FGF-1 variants to protein kinase CK2 correlates with mitogenicity.

Fibroblast growth factor-1 (FGF-1) has both extra- and intracellular functions. To identify intracellular binding partners for FGF-1, we isolated proteins from U2OS human osteosarcoma cells interacting specifically with FGF-1. One of the isolated proteins was identified as protein kinase CK2 (CK2). We here provide evidence that FGF-1 binds to both ...
the catalytic alpha-subunit and to the regulatory beta-subunit of CK2. The interaction between FGF-1 and CK2 alpha and beta was characterized by surface plasmon resonance, giving K(D) values of 0.4 +/- 0.3 and 1.2 +/- 0.2 microM, respectively. By using a novel assay for intracellular protein interaction, FGF-1 and CK2 alpha are shown to interact in vivo. In vitro, FGF-1 and FGF-2 are phosphorylated by CK2, and the presence of FGF-1 or FGF-2 was found to enhance the autophosphorylation of CK2 beta. A correlation between the mitogenic potential of FGF-1 mutants and their ability to bind to CK2 alpha was observed. The possible involvement of CK2 in the FGF-induced stimulation of DNA synthesis is discussed.
Mesh Terms:
Amino Acid Substitution, Binding Sites, Bone Neoplasms, Casein Kinase II, DNA Replication, Fibroblast Growth Factor 1, Hela Cells, Humans, MAP Kinase Signaling System, Macromolecular Substances, Mitosis, Neoplasm Proteins, Osteosarcoma, Peroxisomes, Phosphorylation, Protein Binding, Protein Processing, Post-Translational, Protein Subunits, Protein-Serine-Threonine Kinases, Recombinant Fusion Proteins, Surface Plasmon Resonance, Transfection, Tumor Cells, Cultured
EMBO J.
Date: Aug. 01, 2002
Download Curated Data For This Publication
1548
Switch View:
  • Interactions 11