Fig. 3

SP1 is a direct target gene of miR-320a. a The predicted miR-320a binding site within the SP1 3′UTR and its mutated version are presented. b Restoration of miR-320a in SW480 and SW620 cells induced decreased expression of SP1 mRNA as shown by qPCR assay. c Immunoblotting assays showed restoration of miR-320a in SW480 and SW620 cells suppressed SP1 expression at the protein level. Normalized intensity of each Western blot was analyzed and is annotated below the stripes. d Repression of luciferase activity by the SP1-3′UTR was dependent on miR-320a (P = 0.000), while the 3′UTR-mut of SP1 abrogated miR-320a-mediated repression of luciferase activity (P = 0.000) in 293T cells. miR-146b and TRAF6-3′UTR were used as a positive miRNA and a positive target gene 3′UTR, respectively. PC: positive control; UTR: untranslated region; Mut: mutant