The signalling pathways of interleukin-6 and gamma interferon converge by the activation of different transcription factors which bind to common responsive DNA elements.

摘要: Interleukin-6 (IL-6) and gamma interferon (IFN-gamma) induce a partially overlapping set of genes, including the genes for regulatory factor 1 (IRF-1), intercellular adhesion molecule (ICAM-1), acute-phase protein alpha 2-macroglobulin. We report here that rat 2-macroglobulin promoter is activated by IFN-gamma in human hepatoma (HepG2) cells response element maps to same site previously defined as (APRE), which binds IL-6-activated transcription APRF (acute-phase factor). As was reported fibroblasts, IFN-gamma-regulated GAF phosphorylated at tyrosine after treatment HepG2 cells. posttranslationally activates specifically APRE. This shown be identical or closely related GAF. Although are represent different proteins, their binding sequence specificities very similar. bind equally well APRE sequences various elements IRF-1, ICAM-1, other IFN-gamma-inducible genes. Transient transfection analysis revealed IRF-1 ICAM-1 promoters able confer responsiveness both IL-6 onto heterologous promoter. Therefore, likely involved transcriptional induction these immediate-early IFN-gamma, respectively. Taken together, results demonstrate two functionally distinct hormones, act through common factors sharing almost specificity bind.