Biomaterial Database

Kinase-independent potentiation of B cell antigen receptor-mediated signal transduction by the protein tyrosine kinase Src. 1997

J Lin, and J Tao, and R B Dyer, and N K Herzog, and L B Justement

Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston 77555, USA.

Signal transduction mediated by the B cell Ag receptor involves the activation of multiple protein tyrosine kinases that are members of the Src family (i.e., Fyn, Lyn, Blk, Lck). To determine whether members of the Src family possess common physical and/or enzymatic properties that enable them to potentiate signal transduction via the B cell Ag receptor, we expressed the protein tyrosine kinase Src in the B lymphoma cell line K46-17 mu m lambda. Based on coprecipitation analysis and two-color immunofluorescence, this heterologous Src family kinase was observed to physically associate with the B cell Ag receptor. Additional experiments demonstrated that B cell Ag receptor cross-linking results in increased tyrosine phosphorylation and activation of Src. Several parameters of B cell activation, including tyrosine phosphorylation of intracellular substrates, calcium mobilization, and transcription factor activation, were potentiated in cells that expressed Src when compared with control cells. To determine whether potentiation of Ag receptor-mediated signaling by Src was dependent on its catalytic activity, a kinase-deficient form of Src was expressed in K46-17 mu m lambda cells. Transfectants expressing kinase-deficient Src exhibited an enhanced responsiveness to stimulation through the B cell Ag receptor that was comparable with transfectants expressing wild-type Src. Additionally, kinase-deficient Src was observed to associate with the endogenous kinase Lyn in an activation-dependent manner. These findings indicate that members of the Src family may potentiate Ag receptor-mediated signaling via a kinase-independent mechanism(s) that involves amplification of kinase recruitment to the Ag receptor activation complex.

UI	MeSH Term	Description	Entries
D010766	Phosphorylation	The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.	Phosphorylations
D011505	Protein-Tyrosine Kinases	Protein kinases that catalyze the PHOSPHORYLATION of TYROSINE residues in proteins with ATP or other nucleotides as phosphate donors.	Tyrosine Protein Kinase,Tyrosine-Specific Protein Kinase,Protein-Tyrosine Kinase,Tyrosine Kinase,Tyrosine Protein Kinases,Tyrosine-Specific Protein Kinases,Tyrosylprotein Kinase,Kinase, Protein-Tyrosine,Kinase, Tyrosine,Kinase, Tyrosine Protein,Kinase, Tyrosine-Specific Protein,Kinase, Tyrosylprotein,Kinases, Protein-Tyrosine,Kinases, Tyrosine Protein,Kinases, Tyrosine-Specific Protein,Protein Kinase, Tyrosine-Specific,Protein Kinases, Tyrosine,Protein Kinases, Tyrosine-Specific,Protein Tyrosine Kinase,Protein Tyrosine Kinases,Tyrosine Specific Protein Kinase,Tyrosine Specific Protein Kinases
D011947	Receptors, Antigen, B-Cell	IMMUNOGLOBULINS on the surface of B-LYMPHOCYTES. Their MESSENGER RNA contains an EXON with a membrane spanning sequence, producing immunoglobulins in the form of type I transmembrane proteins as opposed to secreted immunoglobulins (ANTIBODIES) which do not contain the membrane spanning segment.	Antigen Receptors, B-Cell,B-Cell Antigen Receptor,B-Cell Antigen Receptors,Surface Immunoglobulin,Immunoglobulins, Membrane-Bound,Immunoglobulins, Surface,Membrane Bound Immunoglobulin,Membrane-Bound Immunoglobulins,Receptors, Antigen, B Cell,Surface Immunoglobulins,Antigen Receptor, B-Cell,Antigen Receptors, B Cell,B Cell Antigen Receptor,B Cell Antigen Receptors,Bound Immunoglobulin, Membrane,Immunoglobulin, Membrane Bound,Immunoglobulin, Surface,Immunoglobulins, Membrane Bound,Membrane Bound Immunoglobulins,Receptor, B-Cell Antigen,Receptors, B-Cell Antigen
D000081247	CSK Tyrosine-Protein Kinase	Protein tyrosine kinases that phosphorylate tyrosine residues located in the C-terminal tails of SRC-FAMILY KINASES.	C-Terminal Src Kinase,Carboxy-Terminal Src Kinase,Protein Tyrosine Kinase p50(csk),Protein-Tyrosine Kinase C-Terminal Src Kinase,Protein-Tyrosine Kinase c-src,Tyrosine Protein Kinase p50csk,Tyrosine-Protein Kinase CSK,c-src Kinase,c-src Tyrosine Kinase,CSK-src,p50(csk),C Terminal Src Kinase,CSK Tyrosine Protein Kinase,CSK src,CSK, Tyrosine-Protein Kinase,Carboxy Terminal Src Kinase,Kinase CSK, Tyrosine-Protein,Kinase c-src, Protein-Tyrosine,Kinase, C-Terminal Src,Kinase, CSK Tyrosine-Protein,Kinase, Carboxy-Terminal Src,Kinase, c-src,Kinase, c-src Tyrosine,Protein Tyrosine Kinase C Terminal Src Kinase,Protein Tyrosine Kinase c src,Src Kinase, C-Terminal,Src Kinase, Carboxy-Terminal,Tyrosine Kinase, c-src,Tyrosine Protein Kinase CSK,Tyrosine-Protein Kinase, CSK,c src Kinase,c src Tyrosine Kinase,c-src, Protein-Tyrosine Kinase
D000276	Adjuvants, Immunologic	Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (Freund's adjuvant, BCG, Corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity.	Immunoactivators,Immunoadjuvant,Immunoadjuvants,Immunologic Adjuvant,Immunopotentiator,Immunopotentiators,Immunostimulant,Immunostimulants,Adjuvant, Immunologic,Adjuvants, Immunological,Immunologic Adjuvants,Immunological Adjuvant,Adjuvant, Immunological,Immunological Adjuvants
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014407	Tumor Cells, Cultured	Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.	Cultured Tumor Cells,Neoplastic Cells, Cultured,Cultured Neoplastic Cells,Cell, Cultured Neoplastic,Cell, Cultured Tumor,Cells, Cultured Neoplastic,Cells, Cultured Tumor,Cultured Neoplastic Cell,Cultured Tumor Cell,Neoplastic Cell, Cultured,Tumor Cell, Cultured
D014443	Tyrosine	A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.	L-Tyrosine,Tyrosine, L-isomer,para-Tyrosine,L Tyrosine,Tyrosine, L isomer,para Tyrosine
D015398	Signal Transduction	The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.	Cell Signaling,Receptor-Mediated Signal Transduction,Signal Pathways,Receptor Mediated Signal Transduction,Signal Transduction Pathways,Signal Transduction Systems,Pathway, Signal,Pathway, Signal Transduction,Pathways, Signal,Pathways, Signal Transduction,Receptor-Mediated Signal Transductions,Signal Pathway,Signal Transduction Pathway,Signal Transduction System,Signal Transduction, Receptor-Mediated,Signal Transductions,Signal Transductions, Receptor-Mediated,System, Signal Transduction,Systems, Signal Transduction,Transduction, Signal,Transductions, Signal
D016393	Lymphoma, B-Cell	A group of heterogeneous lymphoid tumors generally expressing one or more B-cell antigens or representing malignant transformations of B-lymphocytes.	B-Cell Lymphoma,B Cell Lymphoma,B-Cell Lymphomas,Lymphoma, B Cell,Lymphomas, B-Cell