GATA-1/Foxo3-mediated repression of Exosc8 expression. (A) Real-time RT-PCR analysis of Foxo3, Exosc8 mRNA and primary transcripts upon GATA-1 activation in G1E-ER-GATA-1 cells (mean ± SE; 3 independent experiments). Values were normalized to 18S rRNA expression. (B) Semiquantitative western blot analysis of Foxo3 in G1E-ER-GATA-1 cells after 0, 24, or 48 hours estradiol treatment (left). The representative image is shown from 3 independent experiments. Quantitation of band intensity (mean ± SE; 3 independent experiments) (right). (C) Real-time RT-PCR analysis of Foxo3 and Exosc8 mRNA upon Foxo3 knockdown in G1E-ER-GATA-1 cells after 42 hours activation of GATA-1 (mean ± standard error [SE]; 4 independent experiments). Values were normalized to 18S rRNA expression and expression is shown relative to the control. (D) ChIP-seq profile of GATA-1 occupancy at EXOSC8 in primary human erythroblasts. (E) ChIP analysis of Foxo3 occupancy at the Exosc8 promoter in untreated and estradiol-treated (24 hours) G1E-ER-GATA-1 cells (mean ± SE; 4 independent experiments). (F) Real-time RT-PCR analysis of mRNA levels in control vs Exosc8 knockdown G1E-ER-GATA-1 cells (mean ± SE; 3 independent experiments). Values were normalized to 18S rRNA expression. mRNA levels are shown relative to the control siRNA with estradiol treatment of activated genes (left) and without estradiol treatment of repressed genes (middle). Fold changes upon Exosc8 knockdown relative to control (right). (G) Real-time RT-PCR analysis of primary transcripts in control vs Exosc8 knockdown G1E-ER-GATA-1 cells (mean ± SE; 3 independent experiments). Values were normalized to 18S rRNA expression, and the expression is shown relative to estradiol-treated control siRNA. Fold changes are also depicted upon Exosc8 knockdown relative to control (right). *P < .05, **P < .01, ***P < .001.