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bioRxiv · 10.1101/2025.08.01.667930

Structures of Naked Mole-Rat, Tuco-Tuco, and Guinea Pig Ribosomes: Is rRNA Fragmentation Linked to Translational Fidelity?

Gutierrez-Vargas, C.·De, S.·Maji, S.·Liu, Z.·Ke, Z.·Nieb, M.·Seluanov, A.·Gorbunova, V.·Frank, J.

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Abstract

Ribosomes are central to protein synthesis in all organisms. Among mammals, the ribosome functional core is highly conserved. Remarkably, two rodent species, the naked mole-rat (NMR) and tuco-tuco display fragmented 28S rRNA, coupled with high translational fidelity and long lifespan. The unusual ribosomal architecture in the NMR and tuco-tuco has been speculated to be linked to high translational fidelity. Here we show, by single-particle cryo-electron microscopy (cryo-EM), that despite the fragmentation of their rRNA, NMR and tuco-tuco ribosomes retain their core functional architecture. Compared to ribosomes of the guinea pig, a phylogenetically related rodent without 28S rRNA fragmentation, ribosomes of NMR and tuco-tuco exhibit poorly resolved, certain expansion segments. In contrast, the structure of the guinea pig ribosome shows high similarity to human ribosome. Enhanced translational fidelity in the NMR and tuco-tuco may stem from subtle, allosteric effects in dynamics, linked to rRNA fragmentation.

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Gutierrez-Vargas, C., De, S., Maji, S., Liu, Z., Ke, Z., Nieb, M., Seluanov, A., Gorbunova, V., Frank, J.. 2025-08-02. Structures of Naked Mole-Rat, Tuco-Tuco, and Guinea Pig Ribosomes: Is rRNA Fragmentation Linked to Translational Fidelity?. https://doi.org/10.1101/2025.08.01.667930

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