Figure 6.

Graphical representation of SATB1 expression via alternative promoters in activated (Th0) and polarized (Th2) CD4⁺ T-cells. Activation of non-specific TCR signaling in Th0 cells leads to SATB1 P1 promoter usage. However, in the polarized Th2 cells, activation of cytokine signaling along with TCR activation leads to use of P2 and P3 promoters. Transcription factor STAT6, which acts downstream of the cytokine signaling and NF-κB, which acts downstream of the TCR signaling, positively regulate P2 and P3 promoter usage in polarizing conditions. The switch in promoter usage also correlates with change in SATB1 protein expression. The promoter switch may therefore enable regulation of SATB1 expression in a cell-type specific manner.