STAT protein complexes activated by interferon-gamma and gp130 signaling molecules differ in their sequence preferences and transcriptional induction properties.
Activation of members of the STAT (signal transducers and activators of transcription) family of latent transcription factors is an early event following the binding of many cytokines to their cognate receptors. Although the patterns of STATs activated by different cytokines are well described, the consequences of differential STAT activation are less well studied. We show by mutational analysis that STAT binding elements (SBEs) exist that discriminate between STAT complexes containing STAT1 alpha, STAT3 or both, and that these elements show altered cytokine responsiveness. We also show that in the context of a minimal promoter, single and multiple SBEs exhibit strikingly different patterns of transcriptional activation in response to IFN-gamma, IL-6, OSM or LIF. These differences in transcriptional activation are correlated with the differential ability of these cytokines to activate STAT1 alpha, STAT3 or both. Our results show that the pattern of STATs activated by a cytokine and the arrangement and sequence of the SBEs in the responding promoter have a profound effect on the ability of the cytokine to elicit a transcriptional response.
Lamb
P
P
Ligand Pharmaceuticals, San Diego, CA 92121, USA.
Seidel
H M
HM
Haslam
J
J
Milocco
L
L
Kessler
L V
LV
Stein
R B
RB
Rosen
J
J
D000818:Animals; D015703:Antigens, CD; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D050822:Cytokine Receptor gp130; D016207:Cytokines / Q000494:pharmacology; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D008562:Membrane Glycoproteins / Q000494:pharmacology*; D051379:Mice; D008954:Models, Biological; D008969:Molecular Sequence Data; D017354:Point Mutation; D011401:Promoter Regions, Genetic; D011994:Recombinant Proteins; D050794:STAT1 Transcription Factor; D050796:STAT3 Transcription Factor; D015398:Signal Transduction; D015534:Trans-Activators / Q000378:metabolism*; D015533:Transcriptional Activation
D015703:Antigens, CD; D016207:Cytokines; D004268:DNA-Binding Proteins; C494199:IL6ST protein, human; C494200:Il6st protein, mouse; D008562:Membrane Glycoproteins; D011994:Recombinant Proteins; D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; C494080:Stat1 protein, mouse; C494087:Stat3 protein, mouse; D015534:Trans-Activators; D050822:Cytokine Receptor gp130; D007371:Interferon-gamma; D004247:DNA