FIG. 5.

Expression from a stable MMTV promoter requires the binding of NF1. RNA was isolated from C127, stable clones carrying Wt (pLS-Wt), and NF1 LS mutant promoters, which were treated with DEX for 4 h. (A) Primer extension was performed with 20 μg of total RNA from cell lines containing Wt and mNF1 clones (no. 1 to 4) with oligo-22. The products were run on 8% denaturing polyacrylamide gel. Total RNA samples were run on 1% agarose-Tris-borate-EDTA gel and stained with ethidium bromide. (B) Primer extension was performed with total RNA from Wt and mNF1(no. 1) cell lines with oligo-22 (20 μg of RNA) and 18S-specific primer (2 μg of RNA). (C) Values represent the average of three independent experiments (shown in panel B) after normalization with 18S product. The induced level of expression from the Wt promoter was set to 100.