Fig. 4

SETDB1 was regulated by miR-381-3p in a direct interaction in breast cancer cell lines. a Schematic of potential binding sites for miR-381-3p in the SETDB1 3′-UTR, the seed and the mutated sequences of potential binding sites. Luciferase reporter assays were performed to verify the interaction between miR-381-3p and SETDB1 by cotransfection with SETDB1 3′-UTR-WT or SETDB1 3′-UTR-MUT construct and miR-381-3p mimic into MDA-MB-231 cells (b) and MCF-7 cells (c), or by cotransfection with SETDB1 3′-UTR-WT or SETDB1 3′-UTR-MUT construct and miR-381-3p inhibitor into MDA-MB-231 cells (d) and MCF-7 cells (e). f RIP analysis was used to evaluate the binding between miR-381-3p and SETDB1 using anti-Ago1 in MCF-7 and MDA-MB-231 cells transfected with miR-381-3p mimic, followed by measurement of SETDB1 mRNA by qRT-PCR assay. g Western blot analysis of SETDB1 protein expression in MCF-7 and MDA-MB-231 cells transfected with miR-381-3p mimic or miR-381-3p inhibitor. *P < 0.05 vs. respective negative control