Interaction of IL-10 with its receptor leads to the activation of STAT transcription factors. Herein we report the IL-10 dependent simultaneous activation of three STAT transcription factors: Stat1, Stat3, and Stat5. Upon IL-10 treatment multiple Stat proteins become simultaneously activated, and bind to different promoters with equal kinetics but form distinct homo- and heterodimeric transcriptionally active complexes depending on the STAT-consensus elements of a selected gene promoter. Upon IL-10 treatment Stat1, 3, and 5 bind to the GRR of the FcγRI gene, activated Stat1 and 3 bind to the SIE sequence of the c-fos promoter and transcriptionally active Stat5 assembles at the PRL-STAT consensus sequence of the β-casein gene. Thus, functionally relevant STAT dimerization is influenced by the activated cytokine receptor as well as the specific STAT consensus sequence present in a specific gene promoter.
Wehinger, J., Gouilleux, F., Groner, B., Finke, J., Mertelsmann, R., & Weber-Nordt, R. M. (1996). IL-10 induces DNA binding activity of three STAT proteins (Stat1, Stat3, and Stat5) and their distinct combinatorial assembly in the promoters of selected genes. FEBS Letters, 394(3), 365–370. https://doi.org/10.1016/0014-5793(96)00990-8