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B cell receptor-mediated Syk-independent activation of phosphatidylinositol 3-kinase, Ras, and mitogen-activated protein kinase pathways.
- Source :
-
Journal of immunology (Baltimore, Md. : 1950) [J Immunol] 2003 Aug 01; Vol. 171 (3), pp. 1328-35. - Publication Year :
- 2003
-
Abstract
- The Syk tyrosine kinase is a key molecule in the development of the B cell lineage and the activation of B lymphocytes after Ag recognition by the B cell Ag receptor (BCR). Several genetic studies with chicken B cells have reported that the recruitment of Syk by BCR is essential for activation of a cascade of signaling molecules including phosphatidylinositol 3-kinase, mitogen-activated protein kinases, Ras signaling pathways, phospholipase C-gamma2 activation, and calcium mobilization. The identification of a Syk-deficient mouse IIA1.6/A20 B cell line provided us the opportunity to investigate Syk-mediated signaling in mouse. Surprisingly, phosphatidylinositol 3-kinase, Ras, and mitogen-activated protein kinases were activated upon BCR cross-linking in these Syk-deficient mouse B cells, whereas, as expected from results obtained in chicken B cells, phospholipase C-gamma2 activation and calcium mobilization were impaired as well as the NF-kappaB pathway. These results indicate that BCR signaling is not strictly dependent on Syk expression in mouse IIA1.6/A20 B cells. Thus, B lymphocyte activation may be initiated by Syk-dependent and Syk-independent signaling cascades.
- Subjects :
- Amino Acid Sequence
Animals
Antigens, CD19 physiology
Calcium metabolism
Clone Cells
Enzyme Activation physiology
Enzyme Precursors biosynthesis
Enzyme Precursors deficiency
Enzyme Precursors genetics
Interleukin-2 antagonists & inhibitors
Interleukin-2 metabolism
Intracellular Signaling Peptides and Proteins
Lymphocyte Activation
MAP Kinase Signaling System genetics
Mice
Mitogen-Activated Protein Kinases metabolism
Molecular Sequence Data
NF-kappa B antagonists & inhibitors
NF-kappa B physiology
Phosphatidylinositol 3-Kinases physiology
Phospholipase C gamma
Phosphorylation
Protein-Tyrosine Kinases biosynthesis
Protein-Tyrosine Kinases deficiency
Protein-Tyrosine Kinases genetics
Receptors, Antigen, B-Cell biosynthesis
Signal Transduction genetics
Signal Transduction physiology
Syk Kinase
Tumor Cells, Cultured
Type C Phospholipases metabolism
Tyrosine metabolism
ras Proteins biosynthesis
ras Proteins physiology
Enzyme Precursors physiology
MAP Kinase Signaling System physiology
Phosphatidylinositol 3-Kinases metabolism
Protein-Tyrosine Kinases physiology
Receptors, Antigen, B-Cell physiology
ras Proteins metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0022-1767
- Volume :
- 171
- Issue :
- 3
- Database :
- MEDLINE
- Journal :
- Journal of immunology (Baltimore, Md. : 1950)
- Publication Type :
- Academic Journal
- Accession number :
- 12874222
- Full Text :
- https://doi.org/10.4049/jimmunol.171.3.1328