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bioRxiv · 10.1101/2024.09.20.614200

Unveil the Molecular Interplay between Aminoglycosides and Pseudouridine in IRES Translation

Zhao, Y.·Xu, C.·Chen, X.·Jin, H.·Li, H.
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Abstract

Eukaryotic ribosomes are enriched with pseudouridine, particularly at the functional centers targeted by antibiotics. Here we investigated the roles of pseudouridine in aminoglycoside-mediated translation inhibition by comparing the structural and functional properties of the wild-type ribosomes and those lacking pseudouridine (cbf5-D95A). We showed that the cbf5-D95A ribosomes have decreased thermostability and high sensitivity to aminoglycosides. When presented with an internal ribosome entry site (IRES) RNA, elongation factor eEF2, GTP, sordarin, hygromycin B preferentially binds to the cbf5-D95A ribosomes during initiation by blocking eEF2 binding and stalls the ribosomes in a non-rotated conformation, further hindering translocation. Hygromycin B binds to the inter-subunit bridge B2a that is known to be sensitive to pseudouridine, revealing a functional link between pseudouridine and aminoglycoside inhibition. Our results suggest that pseudouridine enhances both thermostability and conformational fitness of the ribosomes, thereby influencing their susceptibility to aminoglycosides. HighlightsO_LILoss of pseudouridine increases cell sensitivity to aminoglycosides C_LIO_LIPseudouridine enhances ribosome thermostability C_LIO_LIHygromycin B competes with eEF2 for the non-rotated ribosome C_LIO_LIHygromycin B deforms the codon-anticodon duplex C_LI

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Zhao, Y., Xu, C., Chen, X., Jin, H., Li, H.. 2024-09-21. Unveil the Molecular Interplay between Aminoglycosides and Pseudouridine in IRES Translation. https://doi.org/10.1101/2024.09.20.614200

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