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Coxsackievirus B3 Responds to Polyamine Depletion via Enhancement of 2A and 3C Protease Activity

Polyamines are small positively-charged molecules abundant in eukaryotic cells that are crucial to RNA virus replication. In eukaryotic cells, polyamines facilitate processes such as transcription, translation, and DNA replication, and viruses similarly rely on polyamines to facilitate transcription...

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Autores principales: Dial, Courtney N., Tate, Patrick M., Kicmal, Thomas M., Mounce, Bryan C.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2019
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6563312/
https://www.ncbi.nlm.nih.gov/pubmed/31052199
http://dx.doi.org/10.3390/v11050403
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author Dial, Courtney N.
Tate, Patrick M.
Kicmal, Thomas M.
Mounce, Bryan C.
author_facet Dial, Courtney N.
Tate, Patrick M.
Kicmal, Thomas M.
Mounce, Bryan C.
author_sort Dial, Courtney N.
collection PubMed
description Polyamines are small positively-charged molecules abundant in eukaryotic cells that are crucial to RNA virus replication. In eukaryotic cells, polyamines facilitate processes such as transcription, translation, and DNA replication, and viruses similarly rely on polyamines to facilitate transcription and translation. Whether polyamines function at additional stages in viral replication remains poorly understood. Picornaviruses, including Coxsackievirus B3 (CVB3), are sensitive to polyamine depletion both in vitro and in vivo; however, precisely how polyamine function in picornavirus infection has not been described. Here, we describe CVB3 mutants that arise with passage in polyamine-depleted conditions. We observe mutations in the 2A and 3C proteases, and we find that these mutant proteases confer resistance to polyamine depletion. Using a split luciferase reporter system to measure protease activity, we determined that polyamines facilitate viral protease activity. We further observe that the 2A and 3C protease mutations enhance reporter protease activity in polyamine-depleted conditions. Finally, we find that these mutations promote cleavage of cellular eIF4G during infection of polyamine-depleted cells. In sum, our results suggest that polyamines are crucial to protease function during picornavirus infection. Further, these data highlight viral proteases as potential antiviral targets and highlight how CVB3 may overcome polyamine-depleting antiviral therapies.
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spelling pubmed-65633122019-06-17 Coxsackievirus B3 Responds to Polyamine Depletion via Enhancement of 2A and 3C Protease Activity Dial, Courtney N. Tate, Patrick M. Kicmal, Thomas M. Mounce, Bryan C. Viruses Article Polyamines are small positively-charged molecules abundant in eukaryotic cells that are crucial to RNA virus replication. In eukaryotic cells, polyamines facilitate processes such as transcription, translation, and DNA replication, and viruses similarly rely on polyamines to facilitate transcription and translation. Whether polyamines function at additional stages in viral replication remains poorly understood. Picornaviruses, including Coxsackievirus B3 (CVB3), are sensitive to polyamine depletion both in vitro and in vivo; however, precisely how polyamine function in picornavirus infection has not been described. Here, we describe CVB3 mutants that arise with passage in polyamine-depleted conditions. We observe mutations in the 2A and 3C proteases, and we find that these mutant proteases confer resistance to polyamine depletion. Using a split luciferase reporter system to measure protease activity, we determined that polyamines facilitate viral protease activity. We further observe that the 2A and 3C protease mutations enhance reporter protease activity in polyamine-depleted conditions. Finally, we find that these mutations promote cleavage of cellular eIF4G during infection of polyamine-depleted cells. In sum, our results suggest that polyamines are crucial to protease function during picornavirus infection. Further, these data highlight viral proteases as potential antiviral targets and highlight how CVB3 may overcome polyamine-depleting antiviral therapies. MDPI 2019-04-30 /pmc/articles/PMC6563312/ /pubmed/31052199 http://dx.doi.org/10.3390/v11050403 Text en © 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Dial, Courtney N.
Tate, Patrick M.
Kicmal, Thomas M.
Mounce, Bryan C.
Coxsackievirus B3 Responds to Polyamine Depletion via Enhancement of 2A and 3C Protease Activity
title Coxsackievirus B3 Responds to Polyamine Depletion via Enhancement of 2A and 3C Protease Activity
title_full Coxsackievirus B3 Responds to Polyamine Depletion via Enhancement of 2A and 3C Protease Activity
title_fullStr Coxsackievirus B3 Responds to Polyamine Depletion via Enhancement of 2A and 3C Protease Activity
title_full_unstemmed Coxsackievirus B3 Responds to Polyamine Depletion via Enhancement of 2A and 3C Protease Activity
title_short Coxsackievirus B3 Responds to Polyamine Depletion via Enhancement of 2A and 3C Protease Activity
title_sort coxsackievirus b3 responds to polyamine depletion via enhancement of 2a and 3c protease activity
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6563312/
https://www.ncbi.nlm.nih.gov/pubmed/31052199
http://dx.doi.org/10.3390/v11050403
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