Specific inhibition of Stat3 signal transduction by PIAS3.

The signal transducer and activator of transcription-3 (Stat3) protein is activated by the interleukin 6 (IL-6) family of cytokines, epidermal growth factor, and leptin. A protein named PIAS3 (protein inhibitor of activated STAT) that binds to Stat3 was isolated and characterized. The association of PIAS3 with Stat3 in vivo was only observed in cells stimulated with ligands that cause the activation of Stat3. PIAS3 blocked the DNA-binding activity of Stat3 and inhibited Stat3-mediated gene activation. Although Stat1 is also phosphorylated in response to IL-6, PIAS3 did not interact with Stat1 or affect its DNA-binding or transcriptional activity. The results indicate that PIAS3 is a specific inhibitor of Stat3.

[1]  J. Ihle Cytokine receptor signalling , 1995, Nature.

[2]  J. O’Shea Jaks, STATs, cytokine signal transduction, and immunoregulation: are we there yet? , 1997, Immunity.

[3]  I. Verma,et al.  Diverse molecular mechanisms of inhibition of NF-kappa B/DNA binding complexes by I kappa B proteins. , 1993, Gene expression.

[4]  H. Okayama,et al.  Calcium phosphate-mediated gene transfer: a highly efficient transfection system for stably transforming cells with plasmid DNA. , 1988, BioTechniques.

[5]  J. Darnell,et al.  Jak-STAT pathways and transcriptional activation in response to IFNs and other extracellular signaling proteins. , 1994, Science.

[6]  M. Maffei,et al.  Positional cloning of the mouse obese gene and its human homologue , 1994, Nature.

[7]  J. Darnell,et al.  Transcriptional responses to polypeptide ligands: the JAK-STAT pathway. , 1995, Annual review of biochemistry.

[8]  J. Darnell,et al.  A single phosphotyrosine residue of Stat91 required for gene activation by interferon-gamma. , 1993, Science.

[9]  J. Darnell,et al.  Stat3: a STAT family member activated by tyrosine phosphorylation in response to epidermal growth factor and interleukin-6. , 1994, Science.

[10]  J. Darnell,et al.  Leptin activation of Stat3 in the hypothalamus of wild–type and ob/ob mice but not db/db mice , 1996, Nature Genetics.

[11]  S. Akira,et al.  Molecular cloning of APRF, a novel IFN-stimulated gene factor 3 p91-related transcription factor involved in the gp130-mediated signaling pathway , 1994, Cell.

[12]  J. Darnell,et al.  A common nuclear signal transduction pathway activated by growth factor and cytokine receptors. , 1993, Science.

[13]  S. Akira,et al.  Structure and function of a new STAT-induced STAT inhibitor , 1997, Nature.

[14]  J. Darnell,et al.  Maximal activation of transcription by statl and stat3 requires both tyrosine and serine phosphorylation , 1995, Cell.

[15]  J. Darnell,et al.  Activation of transcription by IFN-gamma: tyrosine phosphorylation of a 91-kD DNA binding protein. , 1992, Science.

[16]  S. Akira,et al.  Targeted disruption of the mouse Stat3 gene leads to early embryonic lethality. , 1997, Proceedings of the National Academy of Sciences of the United States of America.