| First Author | Veale M | Year | 1999 |
| Journal | J Biol Chem | Volume | 274 |
| Issue | 40 | Pages | 28427-35 |
| PubMed ID | 10497204 | Mgi Jnum | J:57919 |
| Mgi Id | MGI:1346195 | Doi | 10.1074/jbc.274.40.28427 |
| Citation | Veale M, et al. (1999) Novel isoform of lymphoid adaptor FYN-T-binding protein (FYB-130) interacts with SLP-76 and up-regulates interleukin 2 production. J Biol Chem 274(40):28427-35 |
| abstractText | T-cell activation involves the participation of protein-tyrosine kinases p56(lck) and ZAP-70/SYK as well as lymphoid proteins such as SLP-76 and FYB/SLAP. FYB/SLAP has the hallmarks of an adaptor protein that binds to the SH2 domains of the Src kinase FYN-T and SLP-76. Whereas two forms of FYB at 120 and 130 kDa have been identified biochemically, a cDNA encoding only the lower molecular weight isoform has been cloned (termed FYB-120 or SLAP-130). In this study, we report the isolation of an alternative isoform of FYB with a molecular mass of 130 kDa (FYB-130) that has the same structure as FYB-120 except for an insertion of 46 amino acids toward the carboxyl-terminal region of the protein. FYB-120 and FYB-130 share an ability to bind to the SH2 domains of FYN-T and SLP-76, to act as substrates for p59(FYN-T), and to be expressed in the cytoplasm and nucleus of T-cells. Differences were noted between the isoforms in the efficiency of binding to SLP-76 and in the preferential expression of FYB-130 in mature T-cells. When co-expressed together with FYN-T and SLP-76, FYB-130 caused a significant increase in anti-CD3-driven NF-AT transcription. Finally, fluorescence in situ hybridization analysis localized the FYB gene to human chromosome 5 at position p13.1. FYB-130 therefore represents a novel variant of FYB protein that can up-regulate T-cell receptor-driven interleukin 2 production in mature T-cells. |
