Fig. 1.
Prp5p has ATP-dependent and ATP-independent roles in prespliceosome assembly. Shown is native gel analysis of spliceosome assembly in ATP-depleted splicing extracts. Data are derived from a strain carrying prp5-1 and cus2Δ (5-1 CUS2Δ) preincubated at 25°C (lanes 1–4) or preincubated at 37°C (lanes 5–12) for 10 min (lanes 5–8) or 20 min (lanes 9 –12). Data in lanes 13–16 are from a control extract carrying PRP5+ and cus2Δ (5+CUS2Δ) preincubated at 37°C. Spliceosome assembly is analyzed in the presence (+; lanes 1, 2, 5, 6, 9, 10, 13, and 14) or absence (–; lanes 3, 4, 7, 8, 11, and 12) of exogenous ATP and the presence (+; lanes 2, 4, 6, 8, 10, 12, 14, and 16) or absence (–; lanes 1, 3, 5, 7, 9, 11, 13, and 15) of rPrp5 protein. CC1 and CC2, commitment complexes; P/SP, prespliceosomes/spliceosomes.