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Regulation of phosphoinositide 3-kinase signaling by oxidants: hydrogen peroxide selectively enhances immunoreceptor-induced recruitment of phosphatidylinositol (3,4) bisphosphate-binding PH domain proteins
- Source :
- Cellular signalling. 19(5)
- Publication Year :
- 2006
-
Abstract
- Phosphoinositide 3-kinases (PI3Ks) generate several distinct lipid second messengers including phosphatidylinositol (3,4,5) trisphosphate (PIP3) and phosphatidylinositol (3,4) bisphosphate PI(3,4)P2. PI(3,4)P2 is produced with distinct kinetics and binds to distinct PH domain effector proteins; however, the regulation of this signaling pathway is poorly understood. Superoxides such as hydrogen peroxide are transiently produced after activation through various cell surface receptors and play important roles in immune and inflammatory responses. Here we use quantitative microscopy to examine the effect of peroxide on PI(3,4)P2-mediated mobilization of signaling proteins in B lymphocytes. Peroxide was found to induce dose-dependant membrane recruitment of the PI(3,4)P2-binding PH domain proteins Bam32, TAPP2 and Akt/PKB but not the PIP3-binding PH domain of Btk. Peroxide-induced membrane recruitment was found to be dependant on PI3K activity, with the p110δ isoform contributing much of the activity in the BJAB human B lymphoma model. Strikingly, peroxide co-stimulation enhanced antigen receptor-induced membrane recruitment of Bam32 and TAPP2, with combined stimulation exceeding the maximum achievable with either stimulus alone. Expression of the lipid phosphatase PTEN led to reduction of antigen receptor-induced membrane recruitment of TAPP2; however, peroxide costimulation could overcome the inhibitory effect of PTEN. Inhibition of the NADPH oxidase led to reduction of antigen receptor-induced membrane recruitment of TAPP2. Our results indicate that exogenous and endogenous superoxides can modulate the quality of the PI3K signal in lymphocytes by selectively increasing PI(3,4)P2-dependant signaling.
- Subjects :
- Phosphatidylinositol 3,4-bisphosphate
Green Fluorescent Proteins
Receptors, Antigen, B-Cell
Biology
chemistry.chemical_compound
Mice
Phosphatidylinositol 3-Kinases
Phosphatidylinositol Phosphates
Cell surface receptor
Superoxides
Cell Line, Tumor
Animals
Humans
Phosphatidylinositol
PI3K/AKT/mTOR pathway
Adaptor Proteins, Signal Transducing
B-Lymphocytes
Phosphoinositide 3-kinase
Cell Membrane
Intracellular Signaling Peptides and Proteins
PTEN Phosphohydrolase
Membrane Proteins
Cell Biology
Hydrogen Peroxide
Oxidants
Cell biology
Protein Structure, Tertiary
Pleckstrin homology domain
chemistry
Biochemistry
Second messenger system
biology.protein
Signal transduction
Signal Transduction
Subjects
Details
- ISSN :
- 08986568
- Volume :
- 19
- Issue :
- 5
- Database :
- OpenAIRE
- Journal :
- Cellular signalling
- Accession number :
- edsair.doi.dedup.....68b7b08eae4a6261874f3cba1e83c2c8