Figure 7.
BtTLP catalyzes robust repair of 5′-truncated tRNAPhe substrates. The phosphatase protection assay for G+1 addition was conducted using 5′-32P-labeled C72-tRNAPheΔG+1 (see tRNA diagram) with serial dilutions of BtTLP, MaTLP or yeast Thg1 (yThg1). All reactions contained 1.0 mM GTP and 0.1 mM ATP for activation. The migration of the phosphatase-protected species is consistent with the predicted 6-nt reaction product (see diagram), also confirmed by the addition of a single nucleotide to the 5′-truncated tRNAPheΔG+1 substrate observed using primer extension (see Supplementary Figure S4).