Signaling initiated by overexpression of the fibroblast growth factor receptor-1 investigated by mass spectrometry

Mol Cell Proteomics. 2003 Jan;2(1):29-36. doi: 10.1074/mcp.m200075-mcp200.

Abstract

Overexpression of the fibroblast growth factor receptor-1 (FGFR-1), a prototypic receptor tyrosine kinase, is a feature of several human tumors. In human 293 cells overexpression of the FGFR-1 leads to constitutive activation of the receptor with concomitant sustained high increase in the cellular level of phosphotyrosine-containing proteins. Here we use mass spectrometry to study the tyrosine-phosphorylated proteins induced by overexpression of the FGFR-1. Several well known components of FGFR-1 signaling were identified along with two novel candidates: NS-1-associated protein-1 and target of Myb 1-like protein. We subsequently applied mass spectrometry precursor ion scanning to identify 22 tyrosine phosphorylation sites distributed on six substrate proteins of the FGFR-1 or downstream tyrosine kinases. Novel in vivo tyrosine phosphorylation sites were found in the FGFR-1, phospholipase Cgamma, p90 ribosomal S6 kinase, cortactin, and NS-1-associated protein-1 as a result of sustained FGFR-1 signaling, and we propose these as functional links to downstream molecular and cellular processes.

MeSH terms

  • Blotting, Western
  • Cell Line
  • Cortactin
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme Activation
  • Heterogeneous-Nuclear Ribonucleoproteins*
  • Humans
  • Intracellular Signaling Peptides and Proteins
  • Mass Spectrometry / methods*
  • Microfilament Proteins / metabolism
  • Phosphorylation
  • Precipitin Tests
  • Protein Binding
  • Proteins / chemistry
  • RNA-Binding Proteins / chemistry
  • Receptor Protein-Tyrosine Kinases / chemistry*
  • Receptor Protein-Tyrosine Kinases / metabolism
  • Receptor, Fibroblast Growth Factor, Type 1
  • Receptors, Fibroblast Growth Factor / chemistry*
  • Receptors, Fibroblast Growth Factor / metabolism
  • Ribosomal Protein S6 Kinases, 90-kDa / metabolism
  • Signal Transduction
  • Transfection
  • Tyrosine / metabolism

Substances

  • CTTN protein, human
  • Cortactin
  • Heterogeneous-Nuclear Ribonucleoproteins
  • Intracellular Signaling Peptides and Proteins
  • Microfilament Proteins
  • Proteins
  • RNA-Binding Proteins
  • Receptors, Fibroblast Growth Factor
  • SYNCRIP protein, human
  • TOM1 protein, human
  • Tyrosine
  • FGFR1 protein, human
  • Receptor Protein-Tyrosine Kinases
  • Receptor, Fibroblast Growth Factor, Type 1
  • Ribosomal Protein S6 Kinases, 90-kDa