Fig. 6

JARID1B demethylated H3K4me3 at the CDX2 promoter. a, b Western blot analysis was performed to detect the expression of CDX2, H3K4me3, Histone H3, GSK-3β, Axin2, p-β-catenin, β-catenin, c-MYC and cyclinD1 in DLD-1-shJARID1B and control DLD-1 cells, LOVO-JARID1B and control LOVO cells. c CDX2 promoter reporter luciferase assay using CRC cells transfected with the shJARID1B and shNC plasmid. Western blot was used to detect JARID1B, H3K4me3, CDX2, β-catenin and c-MYC expression in DLD-1 cells transfected with shNC or shJARID1B and in LOVO cells transfected with Vector or Flag-JARID1B. d Schematic representation of the CDX2 promoter and the two predicted H3K4me3 binding elements in the promoter region of the CDX2 gene. Quantitative chromatin immunoprecipitation (qChIP) assays were performed in shJARID1B, control DLD-1 cells, JARID1B-overexpression and control LOVO cells. e When JARID1B knockdown, ChIP qPCR of H3K4me3 to the CDX2 promoter region was up-regulated. In contrast, ChIP qPCR of H3K4me3 to the CDX2 promoter region was down-regulated when JARID1B over-expression, normalized by input. f ChIP qPCR of JARID1B to the CDX2 promoter region was down-regulated when JARID1B knockdown. In contrast, ChIP qPCR of JARID1B to the CDX2 promoter region was up-regulated when JARID1B over-expression, normalized by input. GAPDH as an internal control. *p < 0.05, **p < 0.01, NS: no significant