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bioRxiv · 10.1101/2023.06.18.545436

Enzyme-mediated alkynylation enables transcriptome-wide identification of pseudouridine modifications

Wang, Y.·Zhang, L.·Zhang, W.·Gao, B.·Ye, C.·Dai, Q.·Wang, K.·Luo, M.·Pan, T.·He, C.
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Abstract

Pseudouridine ({Psi}) is one of the most abundant chemical modifications that exists in various types of RNA species and is known to play important roles in RNA function. The advances in studies of {Psi} in less abundant messenger RNA species have been hindered by a lack of suitable methods to precisely and sensitively map their distributions. Here we show that a methyltransferase from Methanocaldococcus jannaschii can label RNA {Psi} efficiently and specifically with various functional groups, both in isolated RNA and inside cells. We leveraged this enzymatic labeling strategy to develop ELAP-seq as a facile method to enrich {Psi}-modified transcripts for the detection of {Psi} modifications at single base resolution with high sensitivity and low background. Using this method, we identified over 10, 000 candidate {Psi} sites from human transcripts, which provides new insights into {Psi} biosynthesis and function. Our study provides a chemical biology method that specifically labels {Psi} for its detection and functional alteration.

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Wang, Y., Zhang, L., Zhang, W., Gao, B., Ye, C., Dai, Q., Wang, K., Luo, M., Pan, T., He, C.. 2023-06-18. Enzyme-mediated alkynylation enables transcriptome-wide identification of pseudouridine modifications. https://doi.org/10.1101/2023.06.18.545436

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