TY - JOUR
T1 - DNA methylation and chromatin structure regulate T cell perforin gene expression
AU - Lu, Qianjin
AU - Wu, Ailing
AU - Ray, Donna
AU - Deng, Chun
AU - Attwood, John
AU - Hanash, Samir
AU - Pipkin, Matthew
AU - Lichtenheld, Mathias
AU - Richardson, Bruce
PY - 2003/5/15
Y1 - 2003/5/15
N2 - Perforin is a cytotoxic effector molecule expressed in NK cells and a subset of T cells. The mechanisms regulating its expression are incompletely understood. We observed that DNA methylation inhibition could increase perforin expression in T cells, so we examined the methylation pattern and chromatin structure of the human perforin promoter and upstream enhancer in primary CD4+ and CD8+ T cells as well as in an NK cell line that expresses perforin, compared with fibroblasts, which do not express perforin. The entire region was nearly completely unmethylated in the NK cell line and largely methylated in fibroblasts. In contrast, only the core promoter was constitutively unmethylated in primary CD4+ and CD8+ cells, and expression was associated with hypomethylation of an area residing between the upstream enhancer at -1 kb and the distal promoter at -0.3 kb. Treating T cells with the DNA methyltransferase inhibitor 5-azacytidine selectively demethylated this area and increased perforin expression. Selective methylation of this region suppressed promoter function in transfection assays. Finally, perforin expression and hypomethylation were associated with localized sensitivity of the 5′ flank to DNase I digestion, indicating an accessible configuration. These results indicate that DNA methylation and chromatin structure participate in the regulation of perforin expression in T cells.
AB - Perforin is a cytotoxic effector molecule expressed in NK cells and a subset of T cells. The mechanisms regulating its expression are incompletely understood. We observed that DNA methylation inhibition could increase perforin expression in T cells, so we examined the methylation pattern and chromatin structure of the human perforin promoter and upstream enhancer in primary CD4+ and CD8+ T cells as well as in an NK cell line that expresses perforin, compared with fibroblasts, which do not express perforin. The entire region was nearly completely unmethylated in the NK cell line and largely methylated in fibroblasts. In contrast, only the core promoter was constitutively unmethylated in primary CD4+ and CD8+ cells, and expression was associated with hypomethylation of an area residing between the upstream enhancer at -1 kb and the distal promoter at -0.3 kb. Treating T cells with the DNA methyltransferase inhibitor 5-azacytidine selectively demethylated this area and increased perforin expression. Selective methylation of this region suppressed promoter function in transfection assays. Finally, perforin expression and hypomethylation were associated with localized sensitivity of the 5′ flank to DNase I digestion, indicating an accessible configuration. These results indicate that DNA methylation and chromatin structure participate in the regulation of perforin expression in T cells.
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U2 - 10.4049/jimmunol.170.10.5124
DO - 10.4049/jimmunol.170.10.5124
M3 - Article
C2 - 12734359
AN - SCOPUS:0037884760
SN - 0022-1767
VL - 170
SP - 5124
EP - 5132
JO - Journal of Immunology
JF - Journal of Immunology
IS - 10
ER -