Fig. 5: YY1 transcriptionally facilitated CTNNB1 expression in CRC cells.

a PROMO database (http://alggen.lsi.upc.es/cgi-bin/promo_v3/promo/promoinit.cgi?dirDB=TF_8.3/) was adopted to predict the potential transcription factors for CTNNB1. The enrichment of these transcription factors on CTNNB1 promoter in response to circAGFG1 knockdown was illustrated using DNA pull-down assay followed by western blot. The schematic diagram of DNA pull-down assay was depicted. b The expression of CTNNB1 was detected by qRT-PCR in CRC cells transfected with shRNAs targeting YY1, ER-alpha and AP-2alphaA. c The binding motif of YY1 was depicted according to JASPAR database (http://jaspar.genereg.net/). The sequence of CTNNB1 promoter with a putative YY1 binding site (TCCATC) or a mutated binding site (AGGTAG) was cloned into pGL3 vector for luciferase reporter assay. d, e After overexpressing YY1, the promoted expression of YY1 (d) and CTNNB1 (e) was detected by qRT-PCR. f Luciferase reporter assay was performed to verify the interaction between YY1 and CTNNB1 promoter. g ChIP assay was conducted to confirm the binding ability between YY1 and CTNNB1 promoter. We repeated the experiments three times to ensure the accuracy of the experiments. ^**P < 0.01.