Human IL-5 promoter harbors several SBSs. (A) A schematic of IL-5 promoter sequence and its truncations used in EMSAs as well as location of identified SBSs and previously published GATA3-binding sites. (B) Increasing concentrations of recombinant SATB1 was incubated with the full-length (615-bp) IL-5 probe and probes A, B, and C. (C) Increasing concentrations of recombinant SATB1 were incubated with probes D, E, F, G, H, and I or with the mutated (without SBSs) probes F, G, H, and I. (D) Increasing concentrations of recombinant SATB1 were incubated with the full-length IL-5 probe and probe C as well as with the corresponding mutated (without SBSs) probes. (E) Increasing concentrations of nuclear lysates from cord blood CD4⁺ T cells polarized to Th1 and Th2 directions for 24 hours were incubated with probe A. (F) Probe A was incubated with 4.0 μg Th1 or Th2 nuclear extract and additionally with anti-SATB1 or normal rabbit IgG. (G) Probe A was incubated with 16.0 μg nuclear extract from cord blood CD4⁺ T cells nucleofected with scrambled (Scr) control or SATB1-siRNA (siR) and cultured in Th2-polarizing conditions for 24 hours and additionally with anti-SATB1 or normal rabbit IgG. The arrow indicates the lysate-probe complex. *Band shift of the complex. The protein concentrations used with each probe are marked in the figure. Data are representative of 3 independent experiments.