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Updated: Aug 9, 2026
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Assessment of Resistance to Tyrosine Kinase Inhibitors by an Interrogation of Signal Transduction Pathways by Antibody Arrays
Published on: September 19, 2018
Cell signaling by protein tyrosine phosphorylation
1Department of Biochemistry, University of Washington, Seattle, USA.
Advances in Enzyme Regulation
|September 2, 1999
Summary
Phosphatases are not simple
Area of Science:
- Cellular biology
- Enzymology
- Molecular signaling
Background:
- Kinases and phosphatases are key regulators of cellular processes.
- Traditional view: phosphatases act as opposing 'off' switches to kinases.
- Emerging evidence suggests a more complex regulatory role.
Discussion:
- Phosphatases can act synergistically with kinases, enhancing phosphorylation.
- Enzyme function (positive or negative determinant) depends on cellular localization and interactions.
- Subcellular localization is a critical determinant of phosphatase activity, more so than catalytic state.
Key Insights:
- Phosphatases are not merely scavenger enzymes.
- Cellular localization dictates whether a phosphatase enhances or opposes kinase activity.
- Targeting localization domains or binding proteins offers a novel therapeutic strategy over modulating catalytic activity.
Outlook:
- Receptor tyrosine phosphatases possess unique structural features, akin to cell adhesion molecules.
- Phosphatases have independent roles in cell development, survival, and death.
- Further research into phosphatase localization and interaction networks is warranted.
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