FIGURE 8.
Mtr4-20p is defective in tRNA-dependent ATPase activity. Purified recombinant Mtr4p was incubated with [α-32P]ATP in the presence of 2.5 μg, 5 μg, or absence of E. coli total tRNA. Aliquots of reactions were collected and stopped by the addition of 0.1% SDS, 5 mM EDTA after 15 min and 60 min at 30°C. Visualization of ATP, ADP, AMP, and Pi was accomplished by incubating 1.0 μCi of [α-32P]ATP and 0.025 U of CIAP together for 15 min at 37°C. Samples were resolved by thin layer chromatography (Materials and Methods), and reaction products were visualized by autoradiography. The positions of ATP, ADP, AMP, and Pi are indicated.