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State-of-the-Art Molecular Virology Research in New Zealand

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A special issue of Viruses (ISSN 1999-4915). This special issue belongs to the section "General Virology".

Deadline for manuscript submissions: closed (15 December 2021) | Viewed by 39070

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Special Issue Editors

Prof. Dr. Vernon Ward

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Guest Editor

University of Otago School of Biomedical Sciencesdisabled, Dunedin, New Zealand

Dr. John A. Taylor

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Guest Editor

School of Biological Sciences, University of Auckland, Auckland, New Zealand
Interests: rotavirus infection; virus vectors; vaccine development

Special Issue Information

Dear Colleagues,

New Zealanders such as R.E.F. (Dick) Matthews and Robert Webster have made world-leading contributions to our understanding of viruses, both plant and animal, for over 50 years. Virology research in New Zealand continues to span a range of viruses, hosts and diseases. In 2020, the outbreak of the SARS-CoV-2 pandemic has brought a new focus on research in virology and its related disciplines. New Zealand scientists and clinicians also contribute to major multinational studies on viral diseases such as influenza and HIV and have been involved in ground-breaking clinical trials to develop successful antiviral drugs. Local virology research now spans all areas of experimental plant, animal and bacterial virology, diagnostic development and epidemiological tracing, viral evolution, phylogenomics, ecology and vertebrate and plant pest control. New Zealand’s expertise in medicinal and synthetic chemistry has driven the development of antiviral drug discovery, novel diagnostic capability and new viral vaccines.

This Special Issue focuses on molecular virology in NZ and will cover a range of virus research topics of importance to New Zealand and the wider world.

Prof. Dr. Vernon Ward
Dr. John A. Taylor
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Viruses is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

molecular virology
viral genomics
cellular virology
direct acting antivirals
epidemiology
plant virology

Published Papers (13 papers)

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24 pages, 7507 KiB

Open AccessArticle

Characterization of the First SARS-CoV-2 Isolates from Aotearoa New Zealand as Part of a Rapid Response to the COVID-19 Pandemic

by Rhodri Harfoot, Blair Lawley, Leonor C. Hernández, Joanna Kuang, Jenny Grant, Jackson M. Treece, Sharon LeQueux, Robert Day, Susan Jack, Jo-Ann L. Stanton, Mihnea Bostina, James E. Ussher and Miguel E. Quiñones-Mateu

Viruses 2022, 14(2), 366; https://0-doi-org.brum.beds.ac.uk/10.3390/v14020366 - 10 Feb 2022

Cited by 8 | Viewed by 3062

Abstract

SARS-CoV-2, the virus responsible for the COVID-19 pandemic, has wreaked havoc across the globe for the last two years. More than 300 million cases and over 5 million deaths later, we continue battling the first real pandemic of the 21st century. SARS-CoV-2 spread quickly, reaching most countries within the first half of 2020, and New Zealand was not an exception. Here, we describe the first isolation and characterization of SARS-CoV-2 variants during the initial virus outbreak in New Zealand. Patient-derived nasopharyngeal samples were used to inoculate Vero cells and, three to four days later, a cytopathic effect was observed in seven viral cultures. Viral growth kinetics was characterized using Vero and VeroE6/TMPRSS2 cells. The identity of the viruses was verified by RT-qPCR, Western blot, indirect immunofluorescence assays, and electron microscopy. Whole-genome sequences were analyzed using two different yet complementary deep sequencing platforms (MiSeq/Illumina and Ion PGM™/Ion Torrent™), classifying the viruses as SARS-CoV-2 B.55, B.31, B.1, or B.1.369 based on the Pango Lineage nomenclature. All seven SARS-CoV-2 isolates were susceptible to remdesivir (EC₅₀ values from 0.83 to 2.42 µM) and β-D-N⁴-hydroxycytidine (molnupiravir, EC₅₀ values from 0.96 to 1.15 µM) but not to favipiravir (>10 µM). Interestingly, four SARS-CoV-2 isolates, carrying the D614G substitution originally associated with increased transmissibility, were more susceptible (2.4-fold) to a commercial monoclonal antibody targeting the spike glycoprotein than the wild-type viruses. Altogether, this seminal work allowed for early access to SARS-CoV-2 isolates in New Zealand, paving the way for numerous clinical and scientific research projects in the country, including the development and validation of diagnostic assays, antiviral strategies, and a national COVID-19 vaccine development program. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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11 pages, 3705 KiB

Open AccessArticle

Cryo-EM Structure of a Possum Enterovirus

by Ivy Wang, Sandeep K. Gupta, Guillaume Ems, Nadishka Jayawardena, Mike Strauss and Mihnea Bostina

Viruses 2022, 14(2), 318; https://0-doi-org.brum.beds.ac.uk/10.3390/v14020318 - 03 Feb 2022

Viewed by 2264

Abstract

Enteroviruses (EVs) represent a substantial concern to global health. Here, we present the cryo-EM structure of a non-human enterovirus, EV-F4, isolated from the Australian brushtail possum to assess the structural diversity of these picornaviruses. The capsid structure, determined to ~3 Å resolution by single particle analysis, exhibits a largely smooth surface, similar to EV-F3 (formerly BEV-2). Although the cellular receptor is not known, the absence of charged residues on the outer surface of the canyon suggest a different receptor type than for EV-F3. Density for the pocket factor is clear, with the entrance to the pocket being smaller than for other enteroviruses. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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15 pages, 2674 KiB

Open AccessArticle

Viromes of Freshwater Fish with Lacustrine and Diadromous Life Histories Differ in Composition

by Benjamin J. Perry, Mitra Mohamadi Darestani, Motia Gulshan Ara, Amélie Hoste, Jennifer M. Jandt, Ludovic Dutoit, Edward C. Holmes, Travis Ingram and Jemma L. Geoghegan

Viruses 2022, 14(2), 257; https://0-doi-org.brum.beds.ac.uk/10.3390/v14020257 - 27 Jan 2022

Cited by 7 | Viewed by 3928

Abstract

Viruses that infect fish are understudied, yet they provide important evolutionary context to the viruses that infect terrestrial vertebrates. We surveyed gill tissue meta-transcriptomes collected from two species of native freshwater fish from Aotearoa New Zealand—Retropinna retropinna and Gobiomorphus cotidianus. A total of 64 fish were used for gill tissue meta-transcriptomic sequencing, from populations with contrasting life histories—landlocked (i.e., lacustrine) and diadromous—on the South Island and Chatham Islands. We observed that both viral richness and taxonomic diversity were significantly associated with life history and host species, with lacustrine R. retropinna characterised by higher viral alpha diversity than diadromous R. retropinna. Additionally, we observed transcripts of fish viruses from 12 vertebrate host-associated virus families, and phylogenetically placed eight novel RNA viruses and three novel DNA viruses in the Astroviridae, Paramyxoviridae, Orthomyxoviridae, Rhabdoviridae, Totiviridae, Poxviridae, Alloherpesviridae, and Adintoviridae in their evolutionary contexts. These results represent an important survey of the viruses that infect two widespread native fish species in New Zealand, and provide insight useful for future fish virus surveys. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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15 pages, 3968 KiB

Open AccessArticle

Characterization of a Novel Double-Stranded RNA Virus from Phytophthora pluvialis in New Zealand

by Zhi Xu, Mahmoud E. Khalifa, Rebekah A. Frampton, Grant R. Smith, Rebecca L. McDougal, Robin M. MacDiarmid and Falk Kalamorz

Viruses 2022, 14(2), 247; https://0-doi-org.brum.beds.ac.uk/10.3390/v14020247 - 26 Jan 2022

Cited by 7 | Viewed by 2773

Abstract

A new dsRNA virus from the oomycete Phytophthora pluvialis has been characterized and designated as Phytophthora pluvialis RNA virus 1 (PplRV1). The genome of the PplRV1 reference genome is 6742 bp that encodes two predicted open reading frames (ORFs). ORF1 and ORF2 overlap by a 47 nt “slippery” frameshift sequence. ORF1 encodes a putative protein of unknown function. ORF2 shows high similarity to the RNA-dependent RNA polymerase (RdRp) of other dsRNA viruses. Phylogenetic analysis of the putative PplRV1 RdRp and its most closely related viruses showed PplRV1 is distinct from other known viruses (below 33% amino acid similarity), which indicates this virus may belong to a new virus family. Analyses of the geographical distribution of PplRV1 in relation to two genetically distinct classes of its host revealed two corresponding genotypes of the PplRV1 (termed a and b), which share 92.3% nt identity. The reference genome for the second genotype is 6760 bp long and a prediction of its genetic organization shows three ORFs, with ORF2 being split into two ORFs, ORF2a and ORF2b, that is conserved in seven of eleven genotype b isolates. Additionally, a quick and simple diagnostic method using qPCR has been developed, which is suitable for large scale screens to identify PplRV1 in Phytophthora. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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16 pages, 2476 KiB

Open AccessArticle

Rapid Response to SARS-CoV-2 in Aotearoa New Zealand: Implementation of a Diagnostic Test and Characterization of the First COVID-19 Cases in the South Island

by Blair Lawley, Jenny Grant, Rhodri Harfoot, Jackson M. Treece, Robert Day, Leonor C. Hernández, Jo-Ann L. Stanton, James E. Ussher and Miguel E. Quiñones-Mateu

Viruses 2021, 13(11), 2222; https://0-doi-org.brum.beds.ac.uk/10.3390/v13112222 - 04 Nov 2021

Cited by 4 | Viewed by 2193

Abstract

It has been 20 months since we first heard of SARS-CoV-2, the novel coronavirus detected in the Hubei province, China, in December 2019, responsible for the ongoing COVID-19 pandemic. Since then, a myriad of studies aimed at understanding and controlling SARS-CoV-2 have been published at a pace that has outshined the original effort to combat HIV during the beginning of the AIDS epidemic. This massive response started by developing strategies to not only diagnose individual SARS-CoV-2 infections but to monitor the transmission, evolution, and global spread of this new virus. We currently have hundreds of commercial diagnostic tests; however, that was not the case in early 2020, when just a handful of protocols were available, and few whole-genome SARS-CoV-2 sequences had been described. It was mid-January 2020 when several District Health Boards across New Zealand started planning the implementation of diagnostic testing for this emerging virus. Here, we describe our experience implementing a molecular test to detect SARS-CoV-2 infection, adapting the RT-qPCR assay to be used in a random-access platform (Hologic Panther Fusion^® System) in a clinical laboratory, and characterizing the first whole-genome SARS-CoV-2 sequences obtained in the South Island, right at the beginning of the SARS-CoV-2 outbreak in New Zealand. We expect that this work will help us and others prepare for the unequivocal risk of similar viral outbreaks in the future. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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23 pages, 5148 KiB

Open AccessArticle

Optimisation of Neuraminidase Expression for Use in Drug Discovery by Using HEK293-6E Cells

by Ashley C. Campbell, John J. Tanner and Kurt L. Krause

Viruses 2021, 13(10), 1893; https://0-doi-org.brum.beds.ac.uk/10.3390/v13101893 - 22 Sep 2021

Cited by 2 | Viewed by 2128

Abstract

Influenza virus is a highly contagious virus that causes significant human mortality and morbidity annually. The most effective drugs for treating influenza are the neuraminidase inhibitors, but resistance to these inhibitors has emerged, and additional drug discovery research on neuraminidase and other targets is needed. Traditional methods of neuraminidase production from embryonated eggs are cumbersome, while insect cell derived protein is less reflective of neuraminidase produced during human infection. Herein we describe a method for producing neuraminidase from a human cell line, HEK293-6E, and demonstrate the method by producing the neuraminidase from the 1918 H1N1 pandemic influenza strain. This method produced high levels of soluble neuraminidase expression (>3000 EU/mL), was enhanced by including a secretion signal from a viral chemokine binding protein, and does not require co-expression of additional proteins. The neuraminidase produced was of sufficient quantity and purity to support high resolution crystal structure determination. The structure solved using this protein conformed to the previously reported structure. Notably the glycosylation at three asparagine residues was superior in quality to that from insect cell derived neuraminidase. This method of production of neuraminidase should prove useful in further studies, such as the characterisation of inhibitor binding. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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22 pages, 4313 KiB

Open AccessArticle

Structural Analysis of the Menangle Virus P Protein Reveals a Soft Boundary between Ordered and Disordered Regions

by Melissa N. Webby, Nicole Herr, Esther M. M. Bulloch, Michael Schmitz, Jeremy R. Keown, David C. Goldstone and Richard L. Kingston

Viruses 2021, 13(9), 1737; https://0-doi-org.brum.beds.ac.uk/10.3390/v13091737 - 31 Aug 2021

Viewed by 2179

Abstract

The paramyxoviral phosphoprotein (P protein) is the non-catalytic subunit of the viral RNA polymerase, and coordinates many of the molecular interactions required for RNA synthesis. All paramyxoviral P proteins oligomerize via a centrally located coiled-coil that is connected to a downstream binding domain by a dynamic linker. The C-terminal region of the P protein coordinates interactions between the catalytic subunit of the polymerase, and the viral nucleocapsid housing the genomic RNA. The inherent flexibility of the linker is believed to facilitate polymerase translocation. Here we report biophysical and structural characterization of the C-terminal region of the P protein from Menangle virus (MenV), a bat-borne paramyxovirus with zoonotic potential. The MenV P protein is tetrameric but can dissociate into dimers at sub-micromolar protein concentrations. The linker is globally disordered and can be modeled effectively as a worm-like chain. However, NMR analysis suggests very weak local preferences for alpha-helical and extended beta conformation exist within the linker. At the interface between the disordered linker and the structured C-terminal binding domain, a gradual disorder-to-order transition occurs, with X-ray crystallographic analysis revealing a dynamic interfacial structure that wraps the surface of the binding domain. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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17 pages, 2272 KiB

Open AccessArticle

Characterisation and Distribution of Karaka Ōkahu Purepure Virus—A Novel Emaravirus Likely to Be Endemic to New Zealand

by Lee O. Rabbidge, Arnaud G. Blouin, Kar Mun Chooi, Colleen M. Higgins and Robin M. MacDiarmid

Viruses 2021, 13(8), 1611; https://0-doi-org.brum.beds.ac.uk/10.3390/v13081611 - 14 Aug 2021

Cited by 8 | Viewed by 2740

Abstract

We report the first emaravirus on an endemic plant of Aotearoa New Zealand that is, to the best of our knowledge, the country’s first endemic virus characterised associated with an indigenous plant. The new-to-science virus was identified in the endemic karaka tree (Corynocarpus laevigatus), and is associated with chlorotic leaf spots, and possible feeding sites of the monophagous endemic karaka gall mite. Of the five negative-sense RNA genomic segments that were fully sequenced, four (RNA 1–4) had similarity to other emaraviruses while RNA 5 had no similarity with other viral proteins. A detection assay developed to amplify any of the five RNAs in a single assay was used to determine the distribution of the virus. The virus is widespread in the Auckland area, particularly in mature trees at Ōkahu Bay, with only occasional reports elsewhere in the North Island. Phylogenetic analysis revealed that its closest relatives are pear chlorotic leaf spot-associated virus and chrysanthemum mosaic-associated virus, which form a unique clade within the genus Emaravirus. Based on the genome structure, we propose this virus to be part of the family Emaravirus, but with less than 50% amino acid similarity to the closest relatives in the most conserved RNA 1, it clearly is a novel species. In consultation with mana whenua (indigenous Māori authority over a territory and its associated treasures), we propose the name Karaka Ōkahu purepure virus in te reo Māori (the Māori language) to reflect the tree from which it was isolated (karaka), a place where the virus is prevalent (Ōkahu), and the spotted symptom (purepure, pronounced pooray pooray) that this endemic virus appears to cause. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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16 pages, 1911 KiB

Open AccessEditor’s ChoiceArticle

A Diverse Viral Community from Predatory Wasps in Their Native and Invaded Range, with a New Virus Infectious to Honey Bees

by Emily J. Remnant, James W. Baty, Mariana Bulgarella, Jana Dobelmann, Oliver Quinn, Monica A. M. Gruber and Philip J. Lester

Viruses 2021, 13(8), 1431; https://0-doi-org.brum.beds.ac.uk/10.3390/v13081431 - 23 Jul 2021

Cited by 9 | Viewed by 2508

Abstract

Wasps of the genus Vespula are social insects that have become major pests and predators in their introduced range. Viruses present in these wasps have been studied in the context of spillover from honey bees, yet we lack an understanding of the endogenous virome of wasps as potential reservoirs of novel emerging infectious diseases. We describe the characterization of 68 novel and nine previously identified virus sequences found in transcriptomes of Vespula vulgaris in colonies sampled from their native range (Belgium) and an invasive range (New Zealand). Many viruses present in the samples were from the Picorna-like virus family (38%). We identified one Luteo-like virus, Vespula vulgaris Luteo-like virus 1, present in the three life stages examined in all colonies from both locations, suggesting this virus is a highly prevalent and persistent infection in wasp colonies. Additionally, we identified a novel Iflavirus with similarity to a recently identified Moku virus, a known wasp and honey bee pathogen. Experimental infection of honey bees with this novel Vespula vulgaris Moku-like virus resulted in an active infection. The high viral diversity present in these invasive wasps is a likely indication that their polyphagous diet is a rich source of viral infections. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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15 pages, 6729 KiB

Open AccessArticle

A Mechanically Transmitted DNA Mycovirus Is Targeted by the Defence Machinery of Its Host, Botrytis cinerea

by Mahmoud E. Khalifa and Robin M. MacDiarmid

Viruses 2021, 13(7), 1315; https://0-doi-org.brum.beds.ac.uk/10.3390/v13071315 - 07 Jul 2021

Cited by 23 | Viewed by 3539

Abstract

Eukaryotic circular single-stranded DNA (ssDNA) viruses were known only to infect plants and vertebrates until the discovery of the isolated DNA mycovirus from the fungus Sclerotinia sclerotiorum. Similar viral sequences were reported from several other sources and classified in ten genera within the Genomoviridae family. The current study reports two circular ssDNA mycoviruses isolated from the phytopathogen Botrytis cinerea, and their assignment to a newly created genus tentatively named Gemydayirivirus. The mycoviruses, tentatively named botrytis gemydayirivirus 1 (BGDaV1) and BGDaV2, are 1701 and 1693 nt long and encode three and two open reading frames (ORFs), respectively. Of the predicted ORFs, only ORF I, which codes for a replication initiation protein (Rep), shared identity with other proteins in GenBank. BGDaV1 is infective as cell-free purified particles and confers hypovirulence on its natural host. Investigation revealed that BGDaV1 is a target for RNA silencing and genomic DNA methylation, keeping the virus at very low titre. The discovery of BGDaV1 expands our knowledge of the diversity of genomoviruses and their interaction with fungal hosts. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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16 pages, 4473 KiB

Open AccessArticle

Norovirus VPg Binds RNA through a Conserved N-Terminal K/R Basic Patch

by Alice M. McSweeney, Vivienne L. Young and Vernon K. Ward

Viruses 2021, 13(7), 1282; https://0-doi-org.brum.beds.ac.uk/10.3390/v13071282 - 30 Jun 2021

Cited by 1 | Viewed by 2106

Abstract

The viral protein genome-linked (VPg) of noroviruses is a multi-functional protein that participates in essential roles during the viral replication cycle. Predictive analyses indicate that murine norovirus (MNV) VPg contains a disordered N-terminal region with RNA binding potential. VPg proteins were expressed with an N-terminal spidroin fusion protein in insect cells and the interaction with RNA investigated by electrophoretic mobility shift assays (EMSA) against a series of RNA probes (pentaprobes) representing all possible five nucleotide combinations. MNV VPg and human norovirus (HuNV) VPg proteins were directly bound to RNA in a non-specific manner. To identify amino acids involved in binding to RNA, all basic (K/R) residues in the first 12 amino acids of MNV VPg were mutated to alanine. Removal of the K/R amino acids eliminated RNA binding and is consistent with a K/R basic patch RNA binding motif within the disordered N-terminal region of norovirus VPgs. Finally, we show that mutation of the K/R basic patch required for RNA binding eliminates the ability of MNV VPg to induce a G0/G1 cell cycle arrest. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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Review

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22 pages, 2097 KiB

Open AccessReview

The Immune Response to SARS-CoV-2 and Variants of Concern

by Elham Torbati, Kurt L. Krause and James E. Ussher

Viruses 2021, 13(10), 1911; https://0-doi-org.brum.beds.ac.uk/10.3390/v13101911 - 23 Sep 2021

Cited by 18 | Viewed by 4150

Abstract

At the end of 2019 a newly emerged betacoronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was identified as the cause of an outbreak of severe pneumonia, subsequently termed COVID-19, in a number of patients in Wuhan, China. Subsequently, SARS-CoV-2 rapidly spread globally, resulting in a pandemic that has to date infected over 200 million individuals and resulted in more than 4.3 million deaths. While SARS-CoV-2 results in severe disease in 13.8%, with increasing frequency of severe disease with age, over 80% of infections are asymptomatic or mild. The immune response is an important determinant of outcome following SARS-CoV-2 infection. While B cell and T cell responses are associated with control of infection and protection against subsequent challenge with SARS-CoV-2, failure to control viral replication and the resulting hyperinflammation are associated with severe COVID-19. Towards the end of 2020, several variants of concern emerged that demonstrate increased transmissibility and/or evasion of immune responses from prior SARS-CoV-2 infection. This article reviews what is known about the humoral and cellular immune responses to SARS-CoV-2 and how mutation and structural/functional changes in the emerging variants of concern impact upon the immune protection from prior infection or vaccination. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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19 pages, 1937 KiB

Open AccessReview

Protein Nucleotidylylation in +ssRNA Viruses

by Alice-Roza Eruera, Alice M. McSweeney, Geena M. McKenzie-Goldsmith and Vernon K. Ward

Viruses 2021, 13(8), 1549; https://0-doi-org.brum.beds.ac.uk/10.3390/v13081549 - 05 Aug 2021

Cited by 4 | Viewed by 3091

Abstract

Nucleotidylylation is a post-transcriptional modification important for replication in the picornavirus supergroup of RNA viruses, including members of the Caliciviridae, Coronaviridae, Picornaviridae and Potyviridae virus families. This modification occurs when the RNA-dependent RNA polymerase (RdRp) attaches one or more nucleotides to a target protein through a nucleotidyl-transferase reaction. The most characterized nucleotidylylation target is VPg (viral protein genome-linked), a protein linked to the 5′ end of the genome in Caliciviridae, Picornaviridae and Potyviridae. The nucleotidylylation of VPg by RdRp is a critical step for the VPg protein to act as a primer for genome replication and, in Caliciviridae and Potyviridae, for the initiation of translation. In contrast, Coronaviridae do not express a VPg protein, but the nucleotidylylation of proteins involved in replication initiation is critical for genome replication. Furthermore, the RdRp proteins of the viruses that perform nucleotidylylation are themselves nucleotidylylated, and in the case of coronavirus, this has been shown to be essential for viral replication. This review focuses on nucleotidylylation within the picornavirus supergroup of viruses, including the proteins that are modified, what is known about the nucleotidylylation process and the roles that these modifications have in the viral life cycle. Full article

(This article belongs to the Special Issue State-of-the-Art Molecular Virology Research in New Zealand)

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