DNase footprinting analysis of the −124 to +37 region. The ability of proteins to bind and protect the core promoter region of the c-kit promoter was analyzed. DNase I digestion for 1 and 2 minutes of the ³²P-labeled DNA fragment was performed with no cell extract (lane 1) and in the presence of 10 and 20 μg of cell extract (right panel). The digested products were analyzed on a 6% sequencing gel. A sequencing reaction of the DNA region was run in parallel (left panel). The sequence of the protected region, corresponding to the −93/−84 SP1 site, is shown.