FIGURE 7.

FACT proteins demonstrate similar effect on HTLV-1 transcription. A and B, the vectors HTLV-1 LTR-luciferase, pTK-Renilla, and BC12-Tax, were co-transfected in HEK293 cells stably expressing shRNAs of SUPT16H (A) or SSRP1 (B). At 48 h post-transfection, luciferase activity was measured and normalized to the Renilla signal. The relative light unit (RLU) of shSUPT16H or shSSRP1 expressing cells was normalized to shNT cells. C, HEK293 cells were transfected with pB-His₆-Tax vector. At 48 h post-transfection, cells were lysed and subjected to IP assays using an anti-SUPT16H or mIgG antibody. Cell lysate and precipitated protein samples were separated by SDS-PAGE. Protein level of His₆-Tax was determined by Western blots using a mouse anti-Tax antibody (4C5). The results were one representative from three independent experiments. The results were one representative from three independent experiments. D, HTLV-1 transformed MT-2 cells were stably transduced with pAPM-shSUPT16H (sh2), shSSRP1 (sh1), or shNT. Cells were lysed, separated by SDS-PAGE, and analyzed by Western blots using anti-SUPT16H or anti-SSRP1 antibody. The GAPDH protein level was determined using an anti-GAPDH antibody to indicate equal loading of protein samples. The results were one representative from three independent experiments. E, cDNA samples from the aforementioned cells treated with SAHA (0.5 μm) were subjected to qPCR assays to measure the HTLV-1 gag/pol mRNA. Level of viral transcripts was normalized to shNT cells. The results throughout are the means of three independent experiments ± S.D. *, p < 0.05 using Student's t test.