Introduction of Dicistrovirus IRESs into UAS/SV40-polyA constructs results in premature polyadenylation and strong overexpression of the upstream ORF in Drosophila animals.

Lidsky, P. V.; Dmitriev, S. E.; Andino, R.

doi:10.1101/2023.10.04.560905

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bioRxiv · 10.1101/2023.10.04.560905

Introduction of Dicistrovirus IRESs into UAS/SV40-polyA constructs results in premature polyadenylation and strong overexpression of the upstream ORF in Drosophila animals.

Lidsky, P. V.·Dmitriev, S. E.·Andino, R.

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Abstract

To evaluate the properties of insect virus internal ribosomal entry sites (IRESs) for protein expression in Drosophila, we have introduced Cricket Paralysis virus (CrPV) and Drosophila C virus (DCV) IRESs into UAS/SV40-polyA vector. We found that introduction of IRESs induce premature polyadenylation, resulting in both truncation of the mRNA, and an increase in mRNA levels of approximately 40-fold. The increase in mRNA levels was accompanied by increased resistance to nonsense-mediated mRNA decay (NMD)-mediated degradation. Our results suggest that premature polyadenylation increases mRNA stability in the SV40 polyadenylation site-containing constructs, suggesting a novel method for robust overexpression of transgenes in Drosophila.

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Lidsky, P. V., Dmitriev, S. E., Andino, R.. 2023-10-05. Introduction of Dicistrovirus IRESs into UAS/SV40-polyA constructs results in premature polyadenylation and strong overexpression of the upstream ORF in Drosophila animals.. https://doi.org/10.1101/2023.10.04.560905

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