Fig. 5

STAT5b strongly enhances the MKL-1 stimulation of the Foxp3 promoter and this effect requires the CArG box. a Schematic of the − 2752 Foxp3 promoter, containing CArG box and GAS elements were linked to a luciferase reporter. Mutation that remove the CArG box or GAS elements (M1-Foxp3-luc, M2-Foxp3-luc and M3-Foxp3-luc); b CD3⁺T cells were transfected with the Wild-Type-2752 Foxp3 promoter, or a M1-Foxp3-luc, M2-Foxp3-luc and M3-Foxp3-luc and transfected with MKL-1 or STAT5b for 48 h. Then the luciferase reporter assays was used to test the transactivity of Foxp3. (**p<0.01, *p<0.05) n = 3; c and d CD3⁺T cells were transiently transfected with a MKL-1, STAT5b, MKL-1 /STAT5b or a control vector (pCDNA3.1) 48 h, and ChIP assays were performed by PCR with primers associated with the genes for Foxp3. Sheared DNA/protein complexes were immunoprecipitated by using an anti-Myc-MKL-1 or anti-flag-STAT5b Ab. Then, PCR was carried out to detect the endogenous CArG regions or GAS regions in immunoprecipitated chromatin fragments. The amount of DNA in each sample (2% input) is shown at the second land. Immunoprecipitations were performed without primary antibody (No Ab) as a control and IgG as a negative control (**p<0.01) n = 3