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bioRxiv · 10.1101/2024.05.14.593974

Structural basis of 3'-tRNA maturation by the human mitochondrial RNAse Z complex

Valentin Gese, G.·Hällberg, B. M.
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Abstract

Human mitochondrial tRNA maturation is essential for cellular energy production, yet the underlying mechanisms remain only partially understood. Here, we present several cryo-EM structures of the mitochondrial RNase Z complex (ELAC2/SDR5C1/TRMT10C) bound to different maturation states of mitochondrial tRNAHis, showing the molecular basis for tRNA-substrate selection and catalysis. Our structural insights provide a molecular rationale for the 5'-to-3' tRNA processing order in mitochondria, the 3'-CCA antideterminant effect, and the basis for sequence-independent recognition of mitochondrial tRNA substrates. Furthermore, the study links mutations in ELAC2 to clinically relevant mitochondrial diseases, offering a deeper understanding of the molecular defects contributing to these conditions.

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Valentin Gese, G., Hällberg, B. M.. 2024-05-14. Structural basis of 3'-tRNA maturation by the human mitochondrial RNAse Z complex. https://doi.org/10.1101/2024.05.14.593974

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