Figures & data
Figure 1. Effect of HTLV-1 Tax varients on the E2-induced BRCA1-Luc and ERE-Luc expression. MCF-7 were co-transfected with either a plasmid expessing BRCA1-Luc (1.5 μg) (A) or ERE-Luc (1.5 μg) (B) alone or together with the indicated combinations of Tax varients (M22, M47 and M89A) expressing plasmids without (left lane) or with (right lane) E2 treatment. The E2 was added to the cultures 5 hr before harvesting the cells for analyzing the reporter expression. The presented results are an average of 3 repeated experiments ± SE.
Figure 2. Effect of CBP/p300 and cyclin T1 on E2- ERα transcriptional activities with or without Tax. MCF-7 were co-transfected with either a plasmid expessing BRCA1-Luc (A) or ERE-Luc (B) alone or with the indicated combinations of w.t.Tax, CBP/ p300, cyclineT1, HEXIMI expressing plasmids without (left lane) or with (right lane) E2 treatment. The E2 was added to the cultures 5 hr before harvesting the cells for analyzing the reporter expression. The presented results are an average of 3 repeated experiments ± SE.
Figure 3. Tax effect on the physical association of E2-ERα with other transcriptional cofactors. MCF-7 cells were or not transfected with 1.5 μg of w.t.Tax expressing plasmid. The indicated cells were treated with E2 at 5 hr before extracting the cells for coimmunoprecipitation (co-IP) analyses. The whole cell extracts were immunoprecipitated with ERα mouse specific monoclonal antibody as indicated in the figure. The various immunoprecipites were analyzed by Western blot analysis with ERα, Ahr, 53Bp1, CBP, Src and Tax rabbit specific monoclonal antibodies.
Figure 4. Effect of Tax on the ERα complex binding to ERE and BRCA1 promoter. MCF-7 cells which were or not transfected with 1.5 μg of Tax variants [w.t.Tax, TaxM22, TaxM47 or Tax(V89A)] as indicated in the figure. The cells were treated with E2 at 5 hr before their extraction for examining the binding of the appropriate proteins to BRCA1 promoter (A) or ERE region (B and C) by CHIP assay as described in Materials and Methods section. Control cells were not transfected with Tax and not treated with E2. The presented results are an average of 3 repeated experiments ± SE.
![Figure 4. Effect of Tax on the ERα complex binding to ERE and BRCA1 promoter. MCF-7 cells which were or not transfected with 1.5 μg of Tax variants [w.t.Tax, TaxM22, TaxM47 or Tax(V89A)] as indicated in the figure. The cells were treated with E2 at 5 hr before their extraction for examining the binding of the appropriate proteins to BRCA1 promoter (A) or ERE region (B and C) by CHIP assay as described in Materials and Methods section. Control cells were not transfected with Tax and not treated with E2. The presented results are an average of 3 repeated experiments ± SE.](/cms/asset/ab62fb90-8d38-4efd-b35d-e297036e1f68/kccy_a_1208871_f0004_oc.gif)
Figure 5. Effect of Tax and E2 on pS2 gene expression. MCF7 cells were transfected with a plasmid expressing Tax, with or without E2 treatment. pS2 mRNA (A) and protein (B) expression levels at 24h post transfection were examined in the total cellular fractions by RT-PCR (as detailed in Material and Methods section) and Western blot analysis (with anti pS2 monoclonal antibody) respectively.
Figure 6. Effect of various co-factors silencing on BRCA1 and pS2 expression. MCF-7 cells were transfected with the shRNAs of the indicated cofactors and treated with E2 w 5 hr before extracting the cells for western blot analysis. The whole cell extracts of the cells were examined for BRACA1 and pS2 expression by western blot analysis with anti BRCA1 and pS2 monoclonal antibodies.
