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Data from: Queuine is a nutritional regulator of Entamoeba histolytica response to oxidative stress and a virulence attenuator

Citation

Ankri, Serge (2021), Data from: Queuine is a nutritional regulator of Entamoeba histolytica response to oxidative stress and a virulence attenuator, Dryad, Dataset, https://doi.org/10.5061/dryad.rv15dv465

Abstract

Queuosine is a naturally occurring modified ribonucleoside found in the first position of the anticodon of the transfer RNAs for Asp, Asn, His and Tyr. Eukaryotes lack pathways to synthesize queuine, the nucleobase precursor to queuosine, and must obtain it from diet or gut microbiota. Here we describe the effects of queuine on the physiology of the eukaryotic parasite, Entamoeba histolytica, the causative agent of amebic dysentery. Queuine is efficiently incorporated into E. histolytica tRNAs by a tRNA-guanine transglycosylase (EhTGT) and this incorporation stimulates the methylation of C38 in tRNAAspGUC.  Queuine protects the parasite against oxidative stress (OS) and antagonizes the negative effect that oxidation has on translation by inducing the expression of genes involved in OS response, such as heat shock protein 70 (Hsp 70), antioxidant enzymes, and enzymes involved in DNA repair. On the other hand, queuine impairs E. histolytica virulence by downregulating the expression of genes previously associated with virulence, including cysteine proteases, cytoskeletal proteins, and small GTPases. Silencing of EhTGT prevents incorporation of queuine into tRNAs and strongly impairs methylation of C38 in tRNAAspGUC, parasite growth, resistance to OS, and cytopathic activity. Overall, our data reveal that queuine plays a dual role in promoting OS resistance and reducing parasite virulence.

Funding

Israel Ministry of Health, INFECT-ERA, Award: 031L0004

Israel Science Foundation, Award: 260/16

National Research Foundation Singapore

Rappaport Institute

US-ISRAEL binational Foundation BSF, Award: 2015211

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