Cloning of a novel T-cell protein FYB that binds FYN and SH2-domain-containing leukocyte protein 76 and modulates interleukin 2 production.

T cell receptor zeta (TcRzeta)/CD3 ligation initiates a signaling cascade that involves src kinases p56(lck) and zeta-associated protein 70, leading to the phosphorylation of substrates such as TcRzeta, Vav, SH2-domain-containing leukocyte protein 76 (SLP-76), cbl, and p120/130. FYN binding protein (FYB or p120/130) associates with p59(fyn), the TcRzeta/CD3 complex, and becomes tyrosine-phosphorylated in response to receptor ligation. In this study, we report the cDNA cloning of human and murine FYB and show that it is restricted in expression to T cells and myeloid cells and possesses an overall unique hydrophilic sequence with several tyrosine-based motifs, proline-based type I and type II SH3 domain binding motifs, several putative lysine/glutamic acid-rich nuclear localization motifs, and a SH3-like domain. In addition to binding the src kinase p59(fyn), FYB binds specifically to the hematopoietic signaling protein SLP-76, an interaction mediated by the SLP-76 SH2 domain. In keeping with this, expression of FYB augmented interleukin 2 secretion from a T cell hybridoma, DC27.10, in response to TcRzeta/CD3 ligation. FYB is therefore a novel hematopoietic protein that acts as a component of the FYN and SLP-76 signaling cascades in T cells.

[1]  R. Laskey,et al.  Nuclear targeting sequences--a consensus? , 1991, Trends in biochemical sciences.

[2]  L. Cantley,et al.  Interaction of Shc with the zeta chain of the T cell receptor upon T cell activation. , 1993, Science.

[3]  G. Koretzky,et al.  Implication of the GRB2-associated phosphoprotein SLP-76 in T cell receptor-mediated interleukin 2 production , 1996, The Journal of experimental medicine.

[4]  C. Rudd,et al.  The T-cell antigen CD5 acts as a receptor and substrate for the protein-tyrosine kinase p56lck , 1994, Molecular and cellular biology.

[5]  J. Rast,et al.  α, β, γ, and δ T Cell Antigen Receptor Genes Arose Early in Vertebrate Phylogeny , 1997 .

[6]  A. Weiss,et al.  Functional activation of the T-cell antigen receptor induces tyrosine phosphorylation of phospholipase C-gamma 1. , 1991, Proceedings of the National Academy of Sciences of the United States of America.

[7]  B. Mayer,et al.  SH3 Domains: Minding your p's and q's , 1995, Current Biology.

[8]  A. Veillette,et al.  Src-related protein tyrosine kinases and T-cell receptor signalling. , 1992, Trends in genetics : TIG.

[9]  T. Pawson,et al.  SH2 domains recognize specific phosphopeptide sequences , 1993, Cell.

[10]  Cook Mp,et al.  Expression of a novel form of the fyn proto-oncogene in hematopoietic cells. , 1989 .

[11]  Arthur Weiss,et al.  ZAP-70: A 70 kd protein-tyrosine kinase that associates with the TCR ζ chain , 1992, Cell.

[12]  C. Rudd,et al.  Biochemical analysis of p120/130: a protein-tyrosine kinase substrate restricted to T and myeloid cells. , 1997, Journal of immunology.

[13]  David H. Williams,et al.  Phosphorylation of SLP-76 by the ZAP-70 Protein-tyrosine Kinase Is Required for T-cell Receptor Function* , 1996, The Journal of Biological Chemistry.

[14]  S. Shoelson,et al.  Rapid T-cell receptor-mediated tyrosine phosphorylation of p120, an Fyn/Lck Src homology 3 domain-binding protein. , 1994, Proceedings of the National Academy of Sciences of the United States of America.

[15]  C. Rudd,et al.  Engagement of the TcR/CD3 complex stimulates p59fyn(T) activity: detection of associated proteins at 72 and 120-130 kD. , 1992, Molecular immunology.

[16]  C. Rudd,et al.  p56Lck and p59Fyn regulate CD28 binding to phosphatidylinositol 3-kinase, growth factor receptor-bound protein GRB-2, and T cell-specific protein-tyrosine kinase ITK: implications for T-cell costimulation. , 1995, Proceedings of the National Academy of Sciences of the United States of America.

[17]  J. Wu,et al.  Vav and SLP-76 interact and functionally cooperate in IL-2 gene activation. , 1996, Immunity.

[18]  A. Weiss,et al.  Sequential interactions of the TCR with two distinct cytoplasmic tyrosine kinases. , 1994, Science.

[19]  G. Koretzky,et al.  Differential Regulation of Activation-induced Tyrosine Phosphorylation and Recruitment of SLP-76 to Vav by Distinct Isoforms of the CD45 Protein-tyrosine Phosphatase* , 1996, The Journal of Biological Chemistry.

[20]  M. Barbacid,et al.  Product of vav proto-oncogene defines a new class of tyrosine protein kinase substrates , 1992, Nature.

[21]  C. Turck,et al.  Molecular Cloning of SLP-76, a 76-kDa Tyrosine Phosphoprotein Associated with Grb2 in T Cells (*) , 1995, The Journal of Biological Chemistry.

[22]  A. Godwin,et al.  A Grb2-associated docking protein in EGF- and insulin-receptor signalling , 1996, Nature.

[23]  L. Samelson,et al.  The protein product of the c-cbl protooncogene is the 120-kDa tyrosine-phosphorylated protein in Jurkat cells activated via the T cell antigen receptor. , 1994, The Journal of biological chemistry.

[24]  P. Stein,et al.  pp59 fyn mutant mice display differential signaling in thymocytes and peripheral T cells , 1992, Cell.

[25]  A. Kong,et al.  p59fyn tyrosine kinase associates with multiple T-cell receptor subunits through its unique amino-terminal domain. , 1992, Molecular and cellular biology.

[26]  L. Ivashkiv Cytokines and STATs: how can signals achieve specificity? , 1995, Immunity.

[27]  L. Samelson,et al.  Complex complexes: signaling at the TCR. , 1996, Immunity.

[28]  O. Janssen,et al.  Two-step TCR zeta/CD3-CD4 and CD28 signaling in T cells: SH2/SH3 domains, protein-tyrosine and lipid kinases. , 1994, Immunology today.

[29]  T. Mustelin T cell antigen receptor signaling: three families of tyrosine kinases and a phosphatase. , 1994, Immunity.

[30]  A. Altman,et al.  Tyrosine kinase-stimulated guanine nucleotide exchange activity of Vav in T cell activation. , 1993, Science.

[31]  S. Lev,et al.  Tyrosine Phosphorylation of Pyk2 Is Selectively Regulated by Fyn During TCR Signaling , 1997, The Journal of experimental medicine.

[32]  J. Fargnoli,et al.  Activation of tyrosine kinase p60fyn following T cell antigen receptor cross-linking. , 1992, The Journal of biological chemistry.

[33]  R. Perlmutter,et al.  Defective T cell receptor signaling in mice lacking the thymic isoform of p59 fyn , 1992, Cell.

[34]  O. Janssen,et al.  T cell receptor zeta/CD3-p59fyn(T)-associated p120/130 binds to the SH2 domain of p59fyn(T) , 1993, The Journal of experimental medicine.

[35]  M. Jenkins The ups and downs of T cell costimulation. , 1994, Immunity.

[36]  K. M. Abraham,et al.  Regulation of T cell receptor signaling by a src family protein-tyrosine kinase (p59 fyn ) , 1991, Cell.