shRNA-based positive selection screening in combination with RNA-seq identifies miR-125b targets that synergize with Gata1s. (A) shRNA⁺ selection screening, in which a pool of shRNAs directed against miR-125b target genes was used to mimic the effect of miR-125b (left). Dot plot showing significantly enriched shRNA-targeted genes (right). Significance was defined as P < .05 (n = 12). Arid3a is highlighted in green. (B) The percentage of Gata1s FLCs expressing doxycycline-regulated miR-125b or miR-ctrl upon addition and removal of doxycycline (500 ng/mL). Arrows indicate time points used for gene expression analysis. Data are the mean ± standard error of the mean (n = 4, paired Student t test). FP⁺, fluorescent protein positive. (C) Venn diagram of differentially expressed genes after miR-125b modulation (compared with miR-ctrl), overlapping with the 13 enriched genes from the shRNA⁺ selection screen in panel A.