ChIP results. The ChIP assay of putative HoxD13 binding sites 1 and 2 in the Gli3 promoter. Only HoxD13 binding site 2 binds HoxD13 in vivo. In lanes 1 and 5, chromatin from rat embryonic hindlimbs was immunoprecipitated with the HoxD13 antibody. In lanes 2 and 6, the Sox9 antibody was used as a negative control. Lanes 3 and 7 show the enzymatic shearing before immunoprecipitation. Genomic DNA was used as a positive control (lanes 4 and 8). Lane M is a size marker.