Figure 5. TCF-1 Directly Regulates Expression of II7r.
(A) Tcf7-VEX or control-VEX retrovirus was transduced into LSK cells from poly (I:C) treated Gata3f/f Mxcre− or Gata3f/f Mxcre+ mice. VEX+ Cells were sorted at 60 hr post-transduction, and the amounts of mRNA were examined by qRT-PCR. Data are from two independent experiments; three or four mice per group (error bars are SEM). **p < 0.05; ns, not significant.
(B) A conversed TCF binding site was identified at a known upstream regulatory region of II7r gene locus.
(C) We cotransfected 293T cells with Tcf7 (or control) retroviral vectors and a luciferase vector containing the −3.6 kb upstream regulatory region of murine II7r gene. TCF-1 (Tcf7) was able to upregulate luciferase reporter activity. The luciferase reporter activity was ablated when the TCF-1 binding site in the −3.6 kb upstream regulatory region was mutated. Data are from two independent experiments. Error bars are SEM from triplicate samples.
(D) ILC2 from lungs of naive mice were expanded in vitro with IL-2, IL-7, and IL-33. ChIP showed that TCF-1 binds to the Gata3-1b promoter and the −3.6 kb upstream regulatory region of II7r locus in ex vivo expanded ILC2. DNA region lacking TCF-1 binding site was used as a negative control. Data are from two independent experiments. Error bars are SEM from triplicate samples. **p < 0.05; ns, not significant. See also Figure S5.