Tyrosine phosphorylation profiling in FGF-2 stimulated human embryonic stem cells
Vanessa M Y Ding1, Paul J Boersema, Leong Yan Foong
1Stem Cell Group, Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore, Singapore.
Plos One
|March 26, 2011
Summary
Fibroblast growth factor-2 (FGF-2) maintains human embryonic stem cells (hESC) by activating multiple signaling pathways. This study identified key tyrosine phosphorylation sites involved in FGF-2 signaling for hESC maintenance.
Area of Science:
- Stem cell biology
- Cell signaling
- Proteomics
Background:
- Fibroblast growth factor-2 (FGF-2) is crucial for maintaining pluripotency in human embryonic stem cells (hESC).
- Understanding the molecular mechanisms of FGF-2 signaling is essential for stem cell research and applications.
Purpose of the Study:
- To investigate the role of FGF-2 in maintaining undifferentiated hESC.
- To profile tyrosine phosphorylation events following FGF-2 stimulation in hESC.
- To identify key signaling proteins regulated by FGF-2 in hESC.
Main Methods:
- Targeted phosphoproteomics approach.
- Stable isotope dimethyl labeling for quantitative analysis.
- Mass spectrometry to identify phosphotyrosine sites and proteins.
Main Results:
- Identified 735 unique tyrosine phosphorylation sites on 430 proteins in hESC.
- Quantitatively profiled temporal tyrosine phosphorylation of 316 peptides from 188 proteins.
- Observed activation of FGF receptors, other receptor tyrosine kinases (RTKs), PI3-K, MAPK, and Src family kinases.
Conclusions:
- FGF-2 signaling involves trans-activation of multiple RTKs and downstream pathways like PI3-K and MAPK.
- Src kinase activation by FGF-2 may regulate cytoskeletal processes essential for maintaining hESC pluripotency.
- This study provides a comprehensive phosphoproteomic landscape of FGF-2 signaling in hESC.
