Figure 3.

Chromatin accessibility at the promoters of the Il2 and Csf2 gene promoters. A - C. Nuclei isolated from unstimulated and stimulated CD4⁺ T cells were digested with MNase (60 U) at 37°C for 5 min, and chromosomal accessibility at the promoter regions of Il2 and Csf2 in unstimulated CD4⁺ T cells (NS) isolated from both age groups of mice (A), or at Il2 (B) and Csf2 (C) following T cell activation by PMA/I was determined by real-time PCR. Primer set A at the promoters of both cytokines, and Il2 set F located 2-kb upstream of Il2 TSS or Csf2 set B were located as shown in Figure 2A. DNA accessibility is calculated based on a method described previously [56]. Every experiment was repeated at least 3 times