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Abstract The endoplasmic reticulum (ER) is a unique organelle responsible for protein synthesis and processing, lipid synthesis in eukaryotic cells, and the replication of many animal viruses is closely related to ER. A considerable number of viral proteins are synthesised during viral infection, resulting in the accumulation of unfolded and misfolded proteins in ER, which in turn induces endoplasmic reticulum stress (ERS). ERS further drives three signalling pathways (PERK, IRE1, and ATF6) of the cellular unfolded protein response (UPR) to respond to the ERS. In numerous studies, ERS has been shown to mediate autophagy, a highly conserved cellular degradation mechanism to maintain cellular homeostasis in eukaryotic cells, through the UPR to restore ER homeostasis. ERS-mediated autophagy is closely linked to the occurrence and development of numerous viral diseases in animals. Host cells can inhibit viral replication by regulating ERS-mediated autophagy, restoring the ER's normal physiological process. Conversely, many viruses have evolved strategies to exploit ERS-mediated autophagy to achieve immune escape. These strategies include the regulation of PERK-eIF2α-Beclin1, PERK-eIF2α-ATF4-ATG12, IRE1α-JNK-Beclin1, and other signalling pathways, which provide favourable conditions for the replication of animal viruses in host cells. The ERS-mediated autophagy pathway has become a hot topic in animal virological research. This article reviews the most recent research regarding the regulatory functions of ERS-mediated autophagy pathways in animal viral infections, emphasising the underlying mechanisms in the context of different viral infections. Furthermore, it considers the future direction and challenges in the development of ERS-mediated autophagy targeting strategies for combating animal viral diseases, which will contribute to unveiling their pathogenic mechanism from a new perspective and provide a scientific reference for the discovery and development of new antiviral drugs and preventive strategies.

The endoplasmic reticulum (ER) is a unique organelle responsible for protein synthesis and processing, lipid synthesis in eukaryotic cells, and the replication of many animal viruses is closely related to ER. A considerable number of viral proteins are synthesised during viral infection, resulting in the accumulation of unfolded and misfolded proteins in ER, which in turn induces endoplasmic reticulum stress (ERS). ERS further drives three signalling pathways (PERK, IRE1, and ATF6) of the cellular unfolded protein response (UPR) to respond to the ERS. In numerous studies, ERS has been shown to mediate autophagy, a highly conserved cellular degradation mechanism to maintain cellular homeostasis in eukaryotic cells, through the UPR to restore ER homeostasis. ERS-mediated autophagy is closely linked to the occurrence and development of numerous viral diseases in animals. Host cells can inhibit viral replication by regulating ERS-mediated autophagy, restoring the ER's normal physiological process. Conversely, many viruses have evolved strategies to exploit ERS-mediated autophagy to achieve immune escape. These strategies include the regulation of PERK-eIF2α-Beclin1, PERK-eIF2α-ATF4-ATG12, IRE1α-JNK-Beclin1, and other signalling pathways, which provide favourable conditions for the replication of animal viruses in host cells. The ERS-mediated autophagy pathway has become a hot topic in animal virological research. This article reviews the most recent research regarding the regulatory functions of ERS-mediated autophagy pathways in animal viral infections, emphasising the underlying mechanisms in the context of different viral infections. Furthermore, it considers the future direction and challenges in the development of ERS-mediated autophagy targeting strategies for combating animal viral diseases, which will contribute to unveiling their pathogenic mechanism from a new perspective and provide a scientific reference for the discovery and development of new antiviral drugs and preventive strategies. [ABSTRACT FROM AUTHOR]

The ban of antiviral drugs in food-producing animals in several parts of the world, latest by Commission Delegated Regulation (EU) 2022/1644, has increased the need for food control laboratories to develop analytical methods and perform official controls. However, little is known about antiviral drugs, their use, and its analysis in food-producing animals in the EU. This review aims to provide insights into relevant viruses, antiviral drugs, and animal-derived matrices for analytical method development and monitoring purposes to implement in food control laboratories. For years, animal viruses, such as African swine fever and avian influenza, have caused many outbreaks. Besides, they led to large economic losses due to the applied control measures and a lack of available treatments. Considering these losses and the known effectiveness of authorized human antiviral drugs in different organisms, medicines such as amantadine in Chinese poultry have been misused. Various analytical methods, including screening assays and sensors (published 2016–2023), and mass spectrometry methods (published 2012–2023) have been outlined in this review for the monitoring of antiviral drugs in animal-derived matrices. However, pharmacokinetics information on metabolite formation and distribution of these substances in different animal-derived matrices is incomplete. Additionally, apart from a few countries, there is a lack of available data on the potential misuse of different antiviral drugs in animal-derived matrices. Although a handful of important antiviral drugs, such as influenza, broad-spectrum, antiretroviral, and herpes drugs, and animal-derived matrices, such as chicken muscle, are identified, the priority of the scope should be further specified by closing the aforementioned gaps.

Aim. Compare the lytic efficiency and the kinetics of accumulation of vesicular stomatitis virus serotypes Indiana (VSV-IND) and New Jersey (VSV-NJ) on cell lines of mouse melanoma B16F10, human hepatocellular carcinoma HepG2 and human mammary adenocarcinoma MCF7.Materials and methods. The viability of mouse melanoma B16F10, human hepatocellular carcinoma HepG2 and human mammary adenocarcinoma MCF7 cell lines infected with VSV-IND and VSV-NJ viruses at different multiplicity of infection (10 MOI; 1 MOI; 0.1 MOI) was assessed after 24, 48 and 72 hours, and the half maximal inhibitory concentration (IC50) values were measured using the methyl tetrazolium test. The relationship with virus accumulation in cell culture was determined using reverse transcription – quantitative polymerase chain reaction; 50% tissue culture infectious dose (TCID50) of VSV-IND and VSV-NJ for B16F10, HepG2, MCF7 were calculated using the Reed-Muench method.Results. The most susceptible cell line for both viruses was B16F10: cell viability 72 hours after infection at 10 MOI was only 10.4% and 5.7% for VSV-IND and VSV-NJ, respectively. HepG2 cell viability at 72 hours post-infection at 10 MOI was 10.8% and 9.8% for VSV-IND and VSV-NJ, and for MCF7 adenocarcinoma it was 46.6% and 36.2%, respectively. Moreover, only in the B16F10 culture was a positive statistically significant correlation of medium strength established between the inhibition of cell viability and the accumulation of viral RNA: for VSV-IND r = 0.601 (p < 0.05); for VSV-NJ r = 0.668 (p < 0.05). HepG2 and MCF7 showed no significant correlation.Conclusion. The research results indicate the potential of using oncolytic viruses of the VSV-IND and VSV-NJ as a platform for the development of new recombinant viruses for virotherapy of solid tumors in combination with other types of treatment.

Nuclear bodies (NBs) are dynamic structures present in eukaryotic cell nuclei. They are not bounded by membranes and are often considered biomolecular condensates, defined structurally and functionally by the localisation of core components. Nuclear architecture can be reorganised during normal cellular processes such as the cell cycle as well as in response to cellular stress. Many plant and animal viruses target their proteins to NBs, in some cases triggering their structural disruption and redistribution. Although not all such interactions have been well characterised, subversion of NBs and their functions may form a key part of the life cycle of eukaryotic viruses that require the nucleus for their replication. This review will focus on Cajal bodies (CBs) and the viruses that target them. Since CBs are dynamic structures, other NBs (principally nucleoli and promyelocytic leukaemia, PML and bodies), whose components interact with CBs, will also be considered. As well as providing important insights into key virus–host cell interactions, studies on Cajal and associated NBs may identify novel cellular targets for development of antiviral compounds. [ABSTRACT FROM AUTHOR]

Nuclear bodies (NBs) are dynamic structures present in eukaryotic cell nuclei. They are not bounded by membranes and are often considered biomolecular condensates, defined structurally and functionally by the localisation of core components. Nuclear architecture can be reorganised during normal cellular processes such as the cell cycle as well as in response to cellular stress. Many plant and animal viruses target their proteins to NBs, in some cases triggering their structural disruption and redistribution. Although not all such interactions have been well characterised, subversion of NBs and their functions may form a key part of the life cycle of eukaryotic viruses that require the nucleus for their replication. This review will focus on Cajal bodies (CBs) and the viruses that target them. Since CBs are dynamic structures, other NBs (principally nucleoli and promyelocytic leukaemia, PML and bodies), whose components interact with CBs, will also be considered. As well as providing important insights into key virus–host cell interactions, studies on Cajal and associated NBs may identify novel cellular targets for development of antiviral compounds.

The ban of antiviral drugs in food-producing animals in several parts of the world, latest by Commission Delegated Regulation (EU) 2022/1644, has increased the need for food control laboratories to develop analytical methods and perform official controls. However, little is known about antiviral drugs, their use, and its analysis in food-producing animals in the EU. This review aims to provide insights into relevant viruses, antiviral drugs, and animal-derived matrices for analytical method development and monitoring purposes to implement in food control laboratories. For years, animal viruses, such as African swine fever and avian influenza, have caused many outbreaks. Besides, they led to large economic losses due to the applied control measures and a lack of available treatments. Considering these losses and the known effectiveness of authorized human antiviral drugs in different organisms, medicines such as amantadine in Chinese poultry have been misused. Various analytical methods, including screening assays and sensors (published 2016-2023), and mass spectrometry methods (published 2012-2023) have been outlined in this review for the monitoring of antiviral drugs in animal-derived matrices. However, pharmacokinetics information on metabolite formation and distribution of these substances in different animal-derived matrices is incomplete. Additionally, apart from a few countries, there is a lack of available data on the potential misuse of different antiviral drugs in animal-derived matrices. Although a handful of important antiviral drugs, such as influenza, broad-spectrum, antiretroviral, and herpes drugs, and animal-derived matrices, such as chicken muscle, are identified, the priority of the scope should be further specified by closing the aforementioned gaps., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Animals have become an essential member for our society, with roles related to company, human well-being and therapy for some diseases, and as a source of food in many populations around the world. Animals intended for human consumption like pigs and cattle, as well as companion animals, specifically cats and dogs, are constantly threatened by multiple viral agents. This puts at risk pet owners and threatens food security in the region. Considering that control or eradication is a complex problem that involves several aspects, there is a limited success in this regard for viral diseases such as foot-and-mouth disease, rabies and classical or African swine fever, this review aims to show the most important characteristics, in the epidemiological context, from farm animals virus, re-emerging viruses affecting companion animals, and emerging and re-emerging zoonotic viruses. Since viral pathogens affect animal populations and human well-being, there is a need to increase efforts to control, monitor and eradicate them from livestock and companion animals. The following sections contribute to improve the understanding of these viral agents and orchestrate actions of control entities in the Americas.

Animals have become an essential member for our society, with roles related to company, human well-being and therapy for some diseases, and as a source of food in many populations around the world. Animals intended for human consumption like pigs and cattle, as well as companion animals, specifically cats and dogs, are constantly threatened by multiple viral agents. This puts at risk pet owners and threatens food security in the region. Considering that control or eradication is a complex problem that involves several aspects, there is a limited success in this regard for viral diseases such as foot-and-mouth disease, rabies and classical or African swine fever, this review aims to show the most important characteristics, in the epidemiological context, from farm animals virus, re-emerging viruses affecting companion animals, and emerging and re-emerging zoonotic viruses. Since viral pathogens affect animal populations and human well-being, there is a need to increase efforts to control, monitor and eradicate them from livestock and companion animals. The following sections contribute to improve the understanding of these viral agents and orchestrate actions of control entities in the Americas. [ABSTRACT FROM AUTHOR]

We investigated the virucidal effects in solution of a new type of disinfectant, calcium bicarbonate mesoscopic crystals, designated CAC-717, against various types of virus. CAC-717 in solution is alkaline (pH 12.4) and has a self-electromotive force that generates pulsed electrical fields. Upon application to human skin, the pH of the solution becomes 8.4. CAC-717 contains no harmful chemicals and is thus non-irritating and harmless to humans and animals. Its virucidal effects were tested against six types of animal virus: enveloped double-strand (ds)-DNA viruses, non-enveloped ds-DNA viruses, non-enveloped single strand (ss)-DNA viruses, enveloped ss-RNA viruses, non-enveloped ss-RNA viruses, and non-enveloped ds-RNA viruses. The treatment resulted in a reduction in viral titer of at least 3.00 log10 to 6.38 log10. Fetal bovine serum was added as a representative organic substance. When its concentration was ≥20%, the virucidal effect of CAC-717 was reduced. Real-time PCR revealed that CAC-717 did not reduce the quantity of genomic DNA of most of the DNA viruses, but it greatly reduced that of the genomic RNA of most of the RNA viruses. CAC-717 may therefore be a useful biosafe disinfectant for use against a broad range of viruses.

Keywords: human viruses; animal viruses; pathogenic viruses; virology; biology; multidisciplinary science While causative viruses for the former do not persist long in individual hosts in general, the latter viruses generate persistent infection and may give rise to latent infection. Human viruses, animal viruses, pathogenic viruses, virology, biology, multidisciplinary science. [Extracted from the article]

Conventional plaque assays rely on the use of overlays to restrict viral infection allowing the formation of distinct foci that grow in time as the replication cycle continues leading to countable plaques that are visualized with standard techniques such as crystal violet, neutral red, or immunolabeling. This classical approach takes several days until large enough plaques can be visualized and counted with some variation due to subjectivity in plaque recognition. Since plaques are clonal lesions produced by virus-induced cytopathic effect, we applied DNA fluorescent dyes with differential cell permeability to visualize them by live-cell imaging. We could observe different stages of that cytopathic effect corresponding to an early wave of cells with chromatin-condensation followed by a wave of dead cells with membrane permeabilization within plaques generated by different animal viruses. This approach enables an automated plaque identification using image analysis to increase single plaque resolution compared to crystal violet counterstaining and allows its application to plaque tracking and plaque reduction assays to test compounds for both antiviral and cytotoxic activities. This fluorescent real-time plaque assay sums to those next-generation technologies by combining this robust classical method with modern fluorescence microscopy and image analysis approaches for future applications in virology.

Adenoviruses (AdVs) infect representatives of numerous species from almost every major vertebrate class, albeit their incidence shows great variability. AdVs infecting birds, reptiles, and bats are the most common and diverse, whereas only one AdV has been so far isolated both from fish and amphibians. The family Adenoviridae is divided into five genera, each corresponding to an independent evolutionary lineage that supposedly coevolved with its respective vertebrate hosts. Members of genera Mastadenovirus and Aviadenovirus seem to infect exclusively mammals and birds, respectively. The genus Ichtadenovirus includes the single known AdV from fish. The majority of AdVs in the genus Atadenovirus originated from squamate reptiles (lizards and snakes), but also certain mammalian and avian AdVs are classified within this genus. The genus Siadenovirus contains the only AdV isolated from frog, along with numerous avian AdVs. In turtles, members of a sixth AdV lineage have been discovered, pending official recognition as an independent genus. The most likely scenario for AdV evolution includes long‐term cospeciation with the hosts, as well as occasional switches between closely or, rarely, more distantly related hosts. [ABSTRACT FROM AUTHOR]

Animal intestines are the source of edible sausage casings, which are traded worldwide and may come from areas where notifiable infectious animal diseases are prevalent. To estimate the risks of virus contamination, knowledge about the quantity of virus and decimal reduction values of the standard preservation method by salting is of great importance. A literature search, based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, was performed in search engine CAB Abstracts to determine the viral load of 14 relevant animal viruses in natural casings or intestines. Only a very limited number of scientific publications per virus were found and viral loads in the intestines varied from high for ASFV (five publications), BVDV (3), CSFV (6), PPRV (3), RPV (2) and TGEV (3) to moderate for PEDV (2) and SVDV (3), low for HEV (2) and FMDV (5), very low for VESV (1) and negative for PrV (2) and VSV (1). PRRSV was found in intestines, however, viral titers were not published. Three viruses (BVDV, CSFV and PPRV) with high viral loads were selected to search for their inactivation kinetics. For casings, no inactivation data were found, however, thermal inactivation data of these viruses were available, but differed in quantity, quality and matrices. In conclusion, important data gaps still exist when it comes to the quantitative inactivation of viruses in sausage casings or livestock intestines.

Our understanding about viruses carried by wild animals is still scarce. The viral diversity of wildlife may be best described with discovery-driven approaches to the study of viral diversity that broaden research efforts towards non-canonical hosts and remote geographic regions. Birds have been key organisms in the transmission of viruses causing important diseases, and wild birds are threatened by viral spillovers associated with human activities. However, our knowledge of the avian virome may be biased towards poultry and highly pathogenic diseases. We describe and compare the fecal virome of two passerine-dominated bird assemblages sampled in a remote Neotropical rainforest in French Guiana (Nouragues Natural Reserve) and a Mediterranean forest in central Spain (La Herrería). We used metagenomic data to quantify the degree of functional and genetic novelty of viruses recovered by examining if the similarity of the contigs we obtained to reference sequences differed between both locations. In general, contigs from Nouragues were significantly less similar to viruses in databases than contigs from La Herrería using Blastn but not for Blastx, suggesting that pristine regions harbor a yet unknown viral diversity with genetically more singular viruses than more studied areas. Additionally, we describe putative novel viruses of the families Picornaviridae, Reoviridae and Hepeviridae. These results highlight the importance of wild animals and remote regions as sources of novel viruses that substantially broaden the current knowledge of the global diversity of viruses.

The Australasian Virology Society (AVS) aims to promote, support and advocate for the discipline of virology in the Australasian region. The society was incorporated in 2011 after 10 years operating as the Australian Virology Group (AVG) founded in 2001, coinciding with the inaugural biennial scientific meeting. AVS conferences aim to provide a forum for the dissemination of all aspects of virology, foster collaboration, and encourage participation by students and post-doctoral researchers. The tenth Australasian Virology Society (AVS10) scientific meeting was held on 2–5 December 2019 in Queenstown, New Zealand. This report highlights the latest research presented at the meeting, which included cutting-edge virology presented by our international plenary speakers Ana Fernandez-Sesma and Benjamin tenOever, and keynote Richard Kuhn. AVS10 honoured female pioneers in Australian virology, Lorena Brown and Barbara Coulson. We report outcomes from the AVS10 career development session on “Successfully transitioning from post-doc to lab head”, winners of best presentation awards, and the AVS gender equity policy, initiated in 2013. Plans for the 2021 meeting are underway which will celebrate the 20th anniversary of AVS where it all began, in Fraser Island, Queensland, Australia.

Swine and poultry viruses, such as porcine reproductive and respiratory syndrome virus (PRRSV), porcine epidemic diarrhea virus (PEDV), and highly pathogenic avian influenza virus (HPAIV), are economically important pathogens that can spread via aerosols. The reliability of methods for quantifying particle-associated viruses as well as the size distribution of aerosolized particles bearing these viruses under field conditions are not well documented. We compared the performance of 2 size-differentiating air samplers in disease outbreaks that occurred in swine and poultry facilities. Both air samplers allowed quantification of particles by size, and measured concentrations of PRRSV, PEDV, and HPAIV stratified by particle size both within and outside swine and poultry facilities. All 3 viruses were detectable in association with aerosolized particles. Proportions of positive sampling events were 69% for PEDV, 61% for HPAIV, and 8% for PRRSV. The highest virus concentrations were found with PEDV, followed by HPAIV and PRRSV. Both air collectors performed equally for the detection of total virus concentration. For all 3 viruses, higher numbers of RNA copies were associated with larger particles; however, a bimodal distribution of particles was observed in the case of PEDV and HPAIV. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) represent a class of small non-coding RNA molecules that can regulate mRNAs by inducing their degradation or by blocking translation. Considering that miRNAs are ubiquitous, stable, and conserved across animal species, it seems feasible to exploit them for clinical applications. Unlike in human viral diseases, where some miRNA-based molecules have progressed to clinical application, in veterinary medicine this concept is just starting to come into view. Clinically, miRNAs could represent a powerful diagnostic tool to pinpoint animal viral diseases and/or prognostic tools to follow up disease progression or remission. Additionally, the possible consequences of miRNA dysregulation make them potential therapeutic targets and open the possibilities to use them as tools to generate viral disease-resistant livestock. This review presents an update of pre-clinical studies on using small non-coding RNAs to combat viral diseases that affect pet and farm animals. Moreover, we discuss the possibilities and challenges of bringing these bench-based discoveries to the veterinary clinic.

Many viruses exploit specific arms of the endomembrane system. The unique composition of each arm prompts the development of remarkably specific interactions between viruses and sub-organelles. This review focuses on the viral-host interactions occurring on the endocytic recycling compartment (ERC), and mediated by its regulatory Ras-related in brain (Rab) GTPase Rab11. This protein regulates trafficking from the ERC and the trans-Golgi network to the plasma membrane. Such transport comprises intricate networks of proteins/lipids operating sequentially from the membrane of origin up to the cell surface. Rab11 is also emerging as a critical factor in an increasing number of infections by major animal viruses, including pathogens that provoke human disease. Understanding the interplay between the ERC and viruses is a milestone in human health. Rab11 has been associated with several steps of the viral lifecycles by unclear processes that use sophisticated diversified host machinery. For this reason, we first explore the state-of-the-art on processes regulating membrane composition and trafficking. Subsequently, this review outlines viral interactions with the ERC, highlighting current knowledge on viral-host binding partners. Finally, using examples from the few mechanistic studies available we emphasize how ERC functions are adjusted during infection to remodel cytoskeleton dynamics, innate immunity and membrane composition. [ABSTRACT FROM AUTHOR]

Animal viruses and bacteria are ubiquitous in the environment. However, little is known about their mode of transmission and etiologic role in human cancers, especially among high-risk groups (e.g., farmers, veterinarians, poultry plant workers, pet owners, and infants). Many factors may affect the survival, transmissibility, and carcinogenicity of these agents, depending on the animal-host environment, hygiene practices, climate, travel, herd immunity, and cultural differences in food consumption and preparation. Seasonal variations in immune function also may increase host susceptibility at certain times of the year. The lack of objective measures, inconsistent study designs, and sources of epidemiologic bias (e.g., residual confounding, recall bias, and non-randomized patient selection) are some of the factors that complicate a clear understanding of this subject.

This document is about betanodaviruses, an emerging group of viruses infecting over 40 marine and some freshwater fish species worldwide1. It details the characteristics of these viruses, including their non-enveloped, icosahedral-shaped capsid and single-stranded, positive-sense RNA2. The document discusses the diseases caused by betanodaviruses, such as viral nervous necrosis (VNN) and viral encephalopathy and retinopathy (VER), which primarily affect the central nervous system of fish34. It also covers prevention and control measures, including good husbandry, biosecurity, and the potential use of vaccines. The document emphasizes the importance of working with fish health professionals for diagnosis and management. First published Dec. 2010.

Many viruses exploit specific arms of the endomembrane system. The unique composition of each arm prompts the development of remarkably specific interactions between viruses and sub-organelles. This review focuses on the viral–host interactions occurring on the endocytic recycling compartment (ERC), and mediated by its regulatory Ras-related in brain (Rab) GTPase Rab11. This protein regulates trafficking from the ERC and the trans-Golgi network to the plasma membrane. Such transport comprises intricate networks of proteins/lipids operating sequentially from the membrane of origin up to the cell surface. Rab11 is also emerging as a critical factor in an increasing number of infections by major animal viruses, including pathogens that provoke human disease. Understanding the interplay between the ERC and viruses is a milestone in human health. Rab11 has been associated with several steps of the viral lifecycles by unclear processes that use sophisticated diversified host machinery. For this reason, we first explore the state-of-the-art on processes regulating membrane composition and trafficking. Subsequently, this review outlines viral interactions with the ERC, highlighting current knowledge on viral-host binding partners. Finally, using examples from the few mechanistic studies available we emphasize how ERC functions are adjusted during infection to remodel cytoskeleton dynamics, innate immunity and membrane composition.

We investigated the virucidal effects in solution of a new type of disinfectant, calcium bicarbonate mesoscopic crystals, designated CAC-717, against various types of virus. CAC-717 in solution is alkaline (pH 12.4) and has a self-electromotive force that generates pulsed electrical fields. Upon application to human skin, the pH of the solution becomes 8.4. CAC-717 contains no harmful chemicals and is thus non-irritating and harmless to humans and animals. Its virucidal effects were tested against six types of animal virus: enveloped double-strand (ds)-DNA viruses, non-enveloped ds-DNA viruses, non-enveloped single strand (ss)-DNA viruses, enveloped ss-RNA viruses, non-enveloped ss-RNA viruses, and non-enveloped ds-RNA viruses. The treatment resulted in a reduction in viral titer of at least 3.00 log10 to 6.38 log10. Fetal bovine serum was added as a representative organic substance. When its concentration was ≥20%, the virucidal effect of CAC-717 was reduced. Real-time PCR revealed that CAC-717 did not reduce the quantity of genomic DNA of most of the DNA viruses, but it greatly reduced that of the genomic RNA of most of the RNA viruses. CAC-717 may therefore be a useful biosafe disinfectant for use against a broad range of viruses. [ABSTRACT FROM AUTHOR]

With their categorical requirement for host ribosomes to translate mRNA, viruses provide a wealth of genetically tractable models to investigate how gene expression is remodeled post-transcriptionally by infection-triggered biological stress. By co-opting and subverting cellular pathways that control mRNA decay, modification, and translation, the global landscape of post-transcriptional processes is swiftly reshaped by virus-encoded factors. Concurrent host cell-intrinsic countermeasures likewise conscript post-transcriptional strategies to mobilize critical innate immune defenses. Here we review strategies and mechanisms that control mRNA decay, modification, and translation in animal virus-infected cells. Besides settling infection outcomes, post-transcriptional gene regulation in virus-infected cells epitomizes fundamental physiological stress responses in health and disease., (© 2022 Burgess et al.; Published by Cold Spring Harbor Laboratory Press.)

Conventional plaque assays rely on the use of overlays to restrict viral infection allowing the formation of distinct foci that grow in time as the replication cycle continues leading to countable plaques that are visualized with standard techniques such as crystal violet, neutral red, or immunolabeling. This classical approach takes several days until large enough plaques can be visualized and counted with some variation due to subjectivity in plaque recognition. Since plaques are clonal lesions produced by virus-induced cytopathic effect, we applied DNA fluorescent dyes with differential cell permeability to visualize them by live-cell imaging. We could observe different stages of that cytopathic effect corresponding to an early wave of cells with chromatin-condensation followed by a wave of dead cells with membrane permeabilization within plaques generated by different animal viruses. This approach enables an automated plaque identification using image analysis to increase single plaque resolution compared to crystal violet counterstaining and allows its application to plaque tracking and plaque reduction assays to test compounds for both antiviral and cytotoxic activities. This fluorescent real-time plaque assay sums to those next-generation technologies by combining this robust classical method with modern fluorescence microscopy and image analysis approaches for future applications in virology. [ABSTRACT FROM AUTHOR]