B-cell signal transduction: tyrosine phosphorylation, kinase activity, and calcium mobilization.
Signal transduction by the B-cell antigen receptor (BCR) regulates development, survival, and clonal expansion of B cells. The BCR complex comprises the membrane-bound immunoglobulin molecule and the Ig-alpha/Ig-beta heterodimer, and was shown to form oligomeric structures. Antigen-mediated engagement of the BCR results in the tyrosine phosphorylation of multiple signaling proteins leading to calcium mobilization and the activation of downstream serine/threonine kinases as well as transcription factors. In pervanadate (PV)-treated B cells, comparable pathways are activated on expression of the BCR, indicating that the BCR can signal in an antigen-independent fashion as well. In this chapter, we describe the analysis of antigen-dependent and -independent tyrosine phosphorylation events as well as a method to study calcium mobilization from differentially stimulated B cells. Furthermore, we emphasize the use of phospho-specific antibodies (Abs) and low-molecular-weight enzyme inhibitors in the process of mapping BCR-activated signaling pathways as well as determining activation states of signaling proteins.
Brummer
Tilman
T
Department of Molecular Immunology, Biology III, University of Freiburg and Max-Planck-Institute for Immunobiology, Freiburg, Germany.
Elis
Winfried
W
Reth
Michael
M
Huber
Michael
M
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D020013:Calcium Signaling / Q000187:drug effects / Q000276:immunology*; D002645:Chickens; D002675:Child, Preschool; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005434:Flow Cytometry; D004854:Herpesvirus 4, Human / Q000235:genetics; D006801:Humans; D008297:Male; D051379:Mice; D019869:Phosphatidylinositol 3-Kinases / Q000276:immunology / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation / Q000187:drug effects; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000276:immunology / Q000378:metabolism*; D011947:Receptors, Antigen, B-Cell / Q000276:immunology / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology*; D014407:Tumor Cells, Cultured; D014443:Tyrosine / Q000276:immunology / Q000378:metabolism*; D014638:Vanadates / Q000494:pharmacology
D004791:Enzyme Inhibitors; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D011505:Protein-Tyrosine Kinases; D011947:Receptors, Antigen, B-Cell; D014443:Tyrosine; D014638:Vanadates; C076715:pervanadate