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Updated: Jul 28, 2026
09:04
Selected Reaction Monitoring Mass Spectrometry for Absolute Protein Quantification
Published on: August 17, 2015
New responsibilities for the PI3K regulatory subunit p85 alpha
K Okkenhaug1, B Vanhaesebroeck
1Ludwig Institute for Cancer Research, University College London Branch, 91 Riding House Street, London W1W 8BT, UK. klaus@ludwig.ucl.ac.uk,
Science'S STKE : Signal Transduction Knowledge Environment
|December 26, 2001
Summary
Class IA phosphoinositide-3 kinases (PI3Ks) regulate cell signaling. New evidence suggests the p85alpha subunit also controls the actin cytoskeleton, prompting a reevaluation of existing knockout mouse studies.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Biology
Background:
- Class IA phosphoinositide-3 kinases (PI3Ks) are crucial heterodimeric enzymes involved in numerous cellular signal transduction pathways.
- PI3Ks consist of a p85 regulatory subunit and a p110 catalytic subunit; p85 recruits p110 to the cell membrane for inositol lipid phosphorylation.
Purpose of the Study:
- To discuss recent findings indicating a novel role for the p85alpha regulatory subunit in modulating the actin cytoskeleton.
- To evaluate the implications of these findings for the interpretation of previous experiments using p85alpha knockout mice.
Main Methods:
- Literature review and discussion of recent experimental evidence.
- Analysis of data from p85alpha knockout mouse models.
Main Results:
- Recent studies suggest p85alpha has a significant function in regulating the actin cytoskeleton, beyond its canonical role in PI3K signaling.
- This emerging role necessitates a critical re-examination of findings from p85alpha knockout mouse studies.
Conclusions:
- The established understanding of p85alpha's function may be incomplete.
- Future research should consider the dual roles of p85alpha in both PI3K signaling and actin cytoskeleton regulation.
- Reinterpretation of existing knockout data is warranted to fully understand p85alpha's biological significance.
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