Effects of TIF-90 expression on FLNA C-terminal (FLNA-C) (16-24) regulated rRNA synthesis. (A) Correlation of FLNA cleavage and TIF-90 expression with rRNA synthesis. AML samples with high levels of FLNA cleavage as determined by western blot were divided into low and high TIF-90 expression groups. The level of rRNA synthesis (left) and the recruitment of Pol I to the rDNA promoter (right) were determined for each set of samples. (B) Effects of TIF-90 depletion and FLNA cleavage on rRNA synthesis and cell survival in primary AML cells. AML samples with high levels of both FLNA cleavage and TIF-90 (n = 5) were transfected with siSCR or siTIF-90 (20 nM). The 5′ETS pre-rRNA (left); ChIP assay and western blot (middle); MTT assay (right). (C and D) Effects of TIF-90 overexpression on the FLNA-C (16-24)–mediated decrease in rRNA synthesis, Pol I binding to rDNA, and cell proliferation. K562 cells were transfected with vector control of FLNA-C (16-24) before transfection with vector control or Myc-TIF-90. (C) The 5′ETS pre-rRNA was measured by qPCR (left); ChIP assay with anti-Pol I antibody (right). Values for qPCR represent the mean ± SD of triplicate determinations. (D) MTT and colony-forming assay (left); western blot (right). (E and F) Effects of TIF-90 overexpression on AZD8055-mediated decrease in rRNA synthesis, Pol I binding to rDNA, and cell proliferation. K562 cells were treated with AZD8055 before transfection with vector control or Myc-TIF-90. (E) Western blot with indicated antibodies. (F) ChIP assay with anti-Pol I antibody (left); 5′ETS pre-rRNA was measured by qPCR (middle); MTT and colony-forming assay (right).