FIG. 7.

Quantitative analysis of the cross-links shown in Fig. 6A, B, and C refers to the three panels of Fig. 6, with the corresponding substrate designations for panel B. The y axis in every case shows the percentage of the cross-linked RNA molecule in the reaction mixture (see Materials and Methods); the x axis shows the time of incubation under splicing conditions (in minutes). The reactions of RNA capped with m⁷GpppG and ApppG are shown on the same graphs. The three graphs in each row show results for U1, U2 and U6 cross-links, respectively, with the identities of the lines shown below. u/s, upstream; d/s, downstream.