Figure 2: Identification of the SOX9 interaction site in the Ctgf gene.

(A) ChIP-on-chip using aSOX9 antibody showed a specific hybridization peak near the transcription initiation site in the Ctgf gene. Exons are shown as solid bars. (B) Validation of the hybridization peak shown in (A) using ChIP-qPCR. QPCR was performed using primers specific for different regions of Ctgf and ChIP-DNA as the template. Primers for the SOX9 interaction site in Col2a1 intron1 were used as a positive control. The other primers used were specific for the peak in (A) (−33/+48), the Ctgf 5′-promoter region (−743/−676) and intron 4 (+1450/+1530). The Y axis showed the level of ChIP DNA by the percentage of input DNA. Values are means ± SEM; *p < 0.01, **p < 0.001.