Hrs is associated with STAM, a signal-transducing adaptor molecule. Its suppressive effect on cytokine-induced cell growth |
| |
Authors: | H Asao Y Sasaki T Arita N Tanaka K Endo H Kasai T Takeshita Y Endo T Fujita K Sugamura |
| |
Affiliation: | Department of Microbiology and Immunology, Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-77, Japan. |
| |
Abstract: | We previously reported a new type of signal-transducing adaptor molecule, STAM, which was shown to be involved in cytokine-mediated intracellular signal transduction. In this study, we molecularly cloned a 110-kDa phosphotyrosine protein inducible by stimulation with interleukin 2 (IL-2). The 110-kDa molecule was found to be a human counterpart of mouse Hrs (hepatocyte growth factor-regulated tyrosine kinase substrate) and to be associated with STAM. Tyrosine phosphorylation of Hrs is induced rapidly after stimulation with IL-2 and granulocyte-macrophage colony-stimulating factor as well as hepatocyte growth factor. The mutual association sites of Hrs and STAM include highly conserved coiled-coil sequences, suggesting that their association is mediated by the coiled-coil structures. Exogenous introduction of the wild-type Hrs significantly suppressed DNA synthesis upon stimulation with IL-2 and granulocyte-macrophage colony-stimulating factor, while the Hrs mutant deleted of the STAM-binding site lost such suppressive ability. These results suggest that Hrs counteracts the STAM function which is critical for cell growth signaling mediated by the cytokines. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|