Fig. 7

PICK1 disrupts the SMAD2/3-DICER1 complex and the processing of pre-miR-615-3p. a MDA-MB-231 cells were transfected with PICK1 or control vectors, and cell lysates were immunoprecipitated with a SMAD2/3 antibody (IP) or a rabbit IgG (control). Representative images show IP and control samples immunoblotted (IB) for PICK1, DICER1, and SMAD2/3. Input: representative western blot of input lysates showing DICER1 expression and β-actin as a loading control. b miRNAs were extracted from the IP and subjected to qRT-PCR assay to detect co-precipitation of pre-miR-615-3p with DICER1 and SMAD2/3. Pre-miR-615-3p expression was normalized and relativized to their correspondent controls. c qRT-PCR assay to detect mature miR-615-3p. d A schematic illustration of the positive feedback loop. miR-615-3p activates Smad2 and Smad3 signaling by suppressing PICK1. In turn, PICK1 downregulates miR-615-3p through disrupting the SMAD2/3-DICER1 complex and the processing of pre-miR-615-3p