TY - JOUR
T1 - Direct interaction of C/EBPδ and Sp1 at the GC-enriched promoter region synergizes the IL-10 gene transcription in mouse macrophage
AU - Chiang, Ben Tzu
AU - Liu, Yi Wen
AU - Chen, Ben Kuen
AU - Wang, Ju Ming
AU - Chang, Wen Chang
N1 - Funding Information:
We thank Drs. Wai-Ming Kan and Tsung-Ping Su for critical reviewing and editing of the manuscript. This work was supported in part by grant the Ministry of Education Program for Promoting Academic Excellent of University under the Grant Number 91-B-FA09-1-4 of the Republic of China and Center for Gene Regulation and Signal Transduction Research, National Cheng Kung University.
PY - 2006/9
Y1 - 2006/9
N2 - We previously reported that LPS activates the transcription of the IL-10 gene through the Sp1 and C/EBP binding sites and indicated that Sp1, C/EBPβ and C/EBPδ can coactivate the IL-10 gene expression in mouse macrophage cells [Liu Y.-W., Tseng H.-P., Chen L.-C., Chen B.-K., Chang W.-C. J. Immunol. 171: 821-828, 2003]. In the present report, we demonstrated the direct physical interaction between C/EBPδ and Sp1, and also mapped the interaction domains of these two proteins. C/EBPδ binds to Sp1 via its basic region leucine zipper domain. The C-terminus of Sp1 was also the major region interacting with C/EBPδ. However, both glutamine- and serine/threonine- rich homologus regions of Sp1 also interacted with C/EBPδ. The binding of Sp1 and C/EBPδ as a complex to the Sp1 binding site on the promoter of IL-10 was further confirmed by using the DNA affinity precipitation assay. By using Sp1-deficient SL2 cells, we also found that the overexpressions of C/EBPδ and Sp1 synergically activate the transcriptional activity of IL-10 gene. Taken together, our present results revealed a novel mechanism of a superactivation of Sp1 by C/EBPδ via a direct interaction between these two transcription factors leading to the activation of the IL-10 gene in mouse macrophage cells.
AB - We previously reported that LPS activates the transcription of the IL-10 gene through the Sp1 and C/EBP binding sites and indicated that Sp1, C/EBPβ and C/EBPδ can coactivate the IL-10 gene expression in mouse macrophage cells [Liu Y.-W., Tseng H.-P., Chen L.-C., Chen B.-K., Chang W.-C. J. Immunol. 171: 821-828, 2003]. In the present report, we demonstrated the direct physical interaction between C/EBPδ and Sp1, and also mapped the interaction domains of these two proteins. C/EBPδ binds to Sp1 via its basic region leucine zipper domain. The C-terminus of Sp1 was also the major region interacting with C/EBPδ. However, both glutamine- and serine/threonine- rich homologus regions of Sp1 also interacted with C/EBPδ. The binding of Sp1 and C/EBPδ as a complex to the Sp1 binding site on the promoter of IL-10 was further confirmed by using the DNA affinity precipitation assay. By using Sp1-deficient SL2 cells, we also found that the overexpressions of C/EBPδ and Sp1 synergically activate the transcriptional activity of IL-10 gene. Taken together, our present results revealed a novel mechanism of a superactivation of Sp1 by C/EBPδ via a direct interaction between these two transcription factors leading to the activation of the IL-10 gene in mouse macrophage cells.
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U2 - 10.1007/s11373-006-9101-y
DO - 10.1007/s11373-006-9101-y
M3 - Article
C2 - 16871431
AN - SCOPUS:33749343200
SN - 1021-7770
VL - 13
SP - 621
EP - 635
JO - Journal of biomedical science
JF - Journal of biomedical science
IS - 5
ER -