In leukaemic cell lines PLZF overexpression downmodulated miR-146a and upregulated CXCR4 protein, whereas PLZF knockdown induced the opposite effects. Our data indicate that megakaryopoiesis is controlled by a cascade pathway, in which PLZF suppresses miR-146a transcription and thereby activates CXCR4 translation.
Here, we show that miR-223 is a direct transcriptional target of AML1/ETO. By recruiting chromatin remodeling enzymes at an AML1-binding site on the pre-miR-223 gene, AML1/ETO induces heterochromatic silencing of miR-223. Ectopic miR-223 expression, RNAi against AML1/ETO, or demethylating treatment enhances miR-223 levels and restores cell differentiation.