Figure 3. In vitro footprinting of the Krt1.12 promoter

DNA fragments representing -394 to -131 and -331 to -109 were prepared from polymerase chain reactions after radioactive labeling at the 5'-end of the sense primers, were incubated with nuclear extracts and digested with DNase I as described in Methods. The concentration of nuclease was 100 ng/ml and nuclear protein was 75 μg. Left lanes showed the control reaction without corneal nuclear protein. Nuclear extract is designated as NE.