A distal cis-regulatory element, CNS-9, controls NFAT1 and IRF4-mediated IL-10 gene activation in T helper cells.
IL-10 is a multifunctional cytokine that plays a critical role in maintaining the balance between immunity and tolerance. Previously, we identified proximal regulatory elements and alterations of chromatin structure in the IL-10 gene loci of Th1 and Th2 cells. We have now characterized a crucial cis-regulatory element, CNS-9, located 9kb upstream of the transcription start site in IL-10 gene loci. The CNS-9 region is highly conserved in vertebrate genomes, and contains clustered NFAT and IRF binding motifs. In vitro binding of NFAT1 and IRF4 to the CNS-9 region was observed by EMSA. Furthermore, Th2-preferential in vivo binding of NFAT1 and IRF4 to the CNS-9 region was observed by ChIP. Cyclosporine A treatment on wild type Th2 cells or Th2 cells derived from NFAT1 knockout (NFAT1(-/-)) mice showed significantly reduced trans-activity of CNS-9. The Th2 subset-specific enhancer activity of CNS-9 was upregulated synergistically by NFAT1 and its partner IRF4. Mutations in the binding sites for NFAT1 and IRF4 abrogated its enhancer activity of CNS-9. Collectively, our results establish crucial roles for enhancer element CNS-9, and NFAT1 and IRF4 that bind to it, for IL-10 expression in differential T helper subsets.
Lee
Choong-Gu
CG
Department of Life Sciences, Gwangju Institute of Science and Technology (GIST), 1 Oryong-dong, Buk-gu, Gwangju 500-712, Republic of Korea.
Kang
Kyu-Ho
KH
So
Jae-Seon
JS
Kwon
Ho-Keun
HK
Son
Jun-Seock
JS
Song
Min-Kyung
MK
Sahoo
Anupama
A
Yi
Hwa-Joong
HJ
Hwang
Ki-Chul
KC
Matsuyama
Toshifumi
T
Yui
Katsuyuki
K
Im
Sin-Hyeog
SH
D000818:Animals; D045744:Cell Line, Tumor; D016572:Cyclosporine / Q000494:pharmacology; D004742:Enhancer Elements, Genetic / Q000235:genetics*; D006801:Humans; D050835:Interferon Regulatory Factors / Q000235:genetics* / Q000378:metabolism; D016753:Interleukin-10 / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D050778:NFATC Transcription Factors / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics; D018417:Th1 Cells / Q000378:metabolism; D018418:Th2 Cells / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D015533:Transcriptional Activation; D000099218:Interferon Regulatory Factor-4
D016572:Cyclosporine; D050835:Interferon Regulatory Factors; D016753:Interleukin-10; D050778:NFATC Transcription Factors; D000099218:Interferon Regulatory Factor-4; C494007:Nfatc2 protein, mouse