Dual-luciferase assay
HEK293T cells were spread to 96 well plates at the concentration of 1×104 cells per well. After 24 hours, HEK293T cells were co-transfected with dual-luciferase reporter vector (pmirGLO-Wt-circ or pmirGLO-Mt-circ, pmirGLO-Wt-3’UTR or pmirGLO-Mt-3’UTR) and miR-204-5p mimics or negative control (miR-NC) using the Lipo-fectomine 3000 transfection reagent (Invitrogen, USA), respectively. After 48h of incubation, firefly and Renilla luciferase activities were measured using a dual-luciferase reporter assay system (Promega, USA) according to the manufacturer’s instructions.