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bioRxiv · 10.1101/474478

Structural and biochemical studies define Nudt12 as a new class of RNA deNADding enzyme in mammalian cells

Grudzien-Nogalska, E.·Wu, Y.·Jiao, X.·Cui, H.·Hart, R. P.·Tong, L.·Kiledjian, M.
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Abstract

We recently demonstrated mammalian cells harbor NAD-capped mRNAs that are hydrolyzed by the DXO deNADding enzyme. Here we report the Nudix protein Nudt12 is a second mammalian deNADding enzyme structurally and mechanistically distinct from DXO and targets different RNAs. Crystal structure of mouse Nudt12 in complex with the deNADding product AMP and three Mg2+ ions at 1.6 [A] resolution provides exquisite insights into the molecular basis of the deNADding activity within the NAD pyrophosphate. Disruption of the Nudt12 gene stabilizes transfected NAD-capped RNA in cells and its endogenous NAD-capped mRNA targets are enriched in those encoding proteins involved in cellular energetics. Furthermore, exposure of cells to metabolic stress manifests changes in NAD-capped RNA levels indicating an association between NAD-capped RNAs and cellular metabolism. Lastly, we show that the bacterial RppH protein also possesses deNADding activity toward NAD-capped RNA but not free NAD, revealing a third class of deNADding enzymes.

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Grudzien-Nogalska, E., Wu, Y., Jiao, X., Cui, H., Hart, R. P., Tong, L., Kiledjian, M.. 2018-11-20. Structural and biochemical studies define Nudt12 as a new class of RNA deNADding enzyme in mammalian cells. https://doi.org/10.1101/474478

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