Biomaterial Database

Association of Src-family kinase Lyn with B-cell antigen receptor. 1993

T Yamamoto, and Y Yamanashi, and K Toyoshima

Institute of Medical Science, University of Tokyo, Japan.

Antigen is thought to cross-link membrane-bound immunoglobulins (Igs) of B cells, causing proliferation and differentiation or the inhibition of growth. Compelling evidence suggests that protein-tyrosine phosphorylation is involved in signal transduction for cell proliferation and differentiation. Indeed cross-linking of membrane-bound IgM (mIgM) induced a rapid increase in tyrosine phosphorylation of at least 10 distinct proteins in B cells. The Src-family protein tyrosine kinase Lyn (p56lyn and p53lyn) is expressed preferentially in B cells. The Lyn protein and its kinase activity could be coimmunoprecipitated with both IgM and IgD from detergent lysates. Cross-linking of membrane-bound IgM with antibody induced down-regulation of the Lyn protein. From these data we concluded that Lyn is physically associated with mIgs. Further evidence showed that cross-linking of mIgM induced rapid increase in the kinase activity of Lyn and association of Lyn with 85-kDa noncatalytic subunit of phosphatidylinositol 3-kinase. Thus, Lyn is likely to participate in B-cell antigen receptor-mediated signaling. As a novel signaling molecule downstream of Lyn, we identified src homology 3-containing, transcription factor-like molecule p75HS1.

UI	MeSH Term	Description	Entries
D007075	Immunoglobulin M	A class of immunoglobulin bearing mu chains (IMMUNOGLOBULIN MU-CHAINS). IgM can fix COMPLEMENT. The name comes from its high molecular weight and originally was called a macroglobulin.	Gamma Globulin, 19S,IgM,IgM Antibody,IgM1,IgM2,19S Gamma Globulin,Antibody, IgM
D008213	Lymphocyte Activation	Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.	Blast Transformation,Blastogenesis,Lymphoblast Transformation,Lymphocyte Stimulation,Lymphocyte Transformation,Transformation, Blast,Transformation, Lymphoblast,Transformation, Lymphocyte,Activation, Lymphocyte,Stimulation, Lymphocyte
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
D001798	Blood Proteins	Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.	Blood Protein,Plasma Protein,Plasma Proteins,Serum Protein,Serum Proteins,Protein, Blood,Protein, Plasma,Protein, Serum,Proteins, Blood,Proteins, Plasma,Proteins, Serum
D002454	Cell Differentiation	Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.	Differentiation, Cell,Cell Differentiations,Differentiations, Cell
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
D001402	B-Lymphocytes	Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.	B-Cells, Lymphocyte,B-Lymphocyte,Bursa-Dependent Lymphocytes,B Cells, Lymphocyte,B Lymphocyte,B Lymphocytes,B-Cell, Lymphocyte,Bursa Dependent Lymphocytes,Bursa-Dependent Lymphocyte,Lymphocyte B-Cell,Lymphocyte B-Cells,Lymphocyte, Bursa-Dependent,Lymphocytes, Bursa-Dependent
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