Primer extension analysis of DMS and CMC modifications of MFA2 T7A0, T7A38, and SP6A0 RNAs. The lanes marked 0, 1, and 2 for the DMS modifications were done at 37°C with no DMS (20 min) and with 1 μl of 1:40 diluted DMS for 5 min and 20 min, respectively. The lanes marked 0, 1, and 2 for the CMC modifications were no CMC (20 min), 50 μl of CMC (42 mg/ml for 3 min), and 50 μl of CMCT (20 min), all at 22°C. Primer extension was done as described in Fig. 1, and the primers used were complementary to the RNA sequence shown at the top. Overall band labeling is shown on the left and modified bands on the right. Fig. 5 shows results that verify the band labeling. The stem 1 and stem 2 labeling on the right was included after these hybridized regions were identified (see Fig. 3).