FIGURE 6.

UV cross-linking analysis of interactions of Pop5 with RNA in the RNase MRP holoenzyme purified from yeast. RNase MRP holoenzyme was purified from yeast, subjected to UV cross-linking, and disassembled under denaturing conditions; then, His₆-tagged Pop5 with cross-linked RNA was isolated, and RNA cross-linked to Pop5 was extracted and finally subjected to primer extension analysis. (Lane 1) RNase MRP RNA extracted from purified holoenzyme and subjected to UV irradiation at 1.28 J/cm² (control for RNA–RNA cross-links); (lanes 2–7) UV-irradiated RNase MRP holoenzyme (0, 0.04, 0.08, 0.16, 0.32, and 0.64 J/cm², respectively); (lane 8) RNase MRP RNA extracted from the purified holoenzyme (control, no irradiation); (lanes 9,10) sequence ladder. 5% denaturing (8 M urea) polyacrylamide gel.