Fig. 3: Structure of the human mitochondrial RNase P complex processing pre-tRNA^His-Ser.

a Cryo-EM density map and cartoon representation of the structure of PRORP poised to process the TRMT10C/SDR5C1-bound pre-tRNA^His-Ser, with the color code indicated in Figure 1a, b. b Substrate-bound PRORP active site, in red loop interacting with the 5′-cleavage site and in pink, loops interacting with the 5′-leader of tRNA^His. c PRORP metal-ion binding in the active site. Residues in the active site and the pre-tRNA^His-Ser are shown in stick representation. Mg1 is shown as a marine sphere (with the density map in marine), and the Mg²⁺ ion labelled Mg2 as a light-purple sphere, was modeled on the basis of the PRORP1 crystal structure (PDB 4G24)¹⁸. d Interactions between the 5′-leader of pre-tRNA^His-Ser and PRORP. e Interactions between the 3′-cleavage site of pre-tRNA^His-Ser and PRORP. f Cleavage assays showing that PRORP activity is dependent on the interaction between PRORP and TRMT10C residues (1-106). Marker M1 is the same as in Fig. 1c, the gel is representative of three experiments, uncropped gel is in Source Data file. WT: TRMT10C/SDR5C1/PRORP/pre-tRNA^His-Ser, (-): PRORP/pre-tRNA^His-Ser, Δ(xx-yy): TRMT10C Δ(xx-yy)/SDR5C1/PRORP/ pre-tRNA^His-Ser, the location on the TRMT10C structure of the NTD residues 80, 106 and 166 are shown in a.