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Journal of Molecular Biology Aug 2016The host innate immune system serves as the first line of defense against viral infections. Germline-encoded pattern recognition receptors detect molecular patterns... (Review)
Review
The host innate immune system serves as the first line of defense against viral infections. Germline-encoded pattern recognition receptors detect molecular patterns associated with pathogens and activate innate immune responses. Of particular relevance to viral infections are those pattern recognition receptors that activate type I interferon responses, which establish an antiviral state. The order Mononegavirales is composed of viruses that possess single-stranded, non-segmented negative-sense (NNS) RNA genomes and are important human pathogens that consistently antagonize signaling related to type I interferon responses. NNS viruses have limited encoding capacity compared to many DNA viruses, and as a likely consequence, most open reading frames encode multifunctional viral proteins that interact with host factors in order to evade host cell defenses while promoting viral replication. In this review, we will discuss the molecular mechanisms of innate immune evasion by select NNS viruses. A greater understanding of these interactions will be critical in facilitating the development of effective therapeutics and viral countermeasures.
Topics: Animals; Host-Pathogen Interactions; Humans; Immune Evasion; Immune Tolerance; Immunity, Innate; Models, Biological; Models, Molecular; Mononegavirales
PubMed: 27487481
DOI: 10.1016/j.jmb.2016.07.017 -
Archives of Virology Jul 2019In February 2019, following the annual taxon ratification vote, the order Mononegavirales was amended by the addition of four new subfamilies and 12 new genera and the...
In February 2019, following the annual taxon ratification vote, the order Mononegavirales was amended by the addition of four new subfamilies and 12 new genera and the creation of 28 novel species. This article presents the updated taxonomy of the order Mononegavirales as now accepted by the International Committee on Taxonomy of Viruses (ICTV).
Topics: Genome, Viral; Mononegavirales; RNA, Viral
PubMed: 31089958
DOI: 10.1007/s00705-019-04247-4 -
Frontiers in Bioscience (Landmark... Jan 2013Matrix proteins are essential components of most negative-sense RNA, enveloped viruses. They serve a wide range of duties ranging from self-driven membrane budding and... (Review)
Review
Matrix proteins are essential components of most negative-sense RNA, enveloped viruses. They serve a wide range of duties ranging from self-driven membrane budding and coordination of other viral components to modulation of viral transcription. The functional similarity between these proteins is striking, despite major differences in their structures. Whereas biochemical and structural studies have partly been hindered by the inherent aggregation properties of these proteins, their cellular functions are beginning to be understood. In this review we summarize the current knowledge on negative-sense RNA virus matrix proteins and their interactions with other viral and cellular proteins. We also discuss the similarities and differences in matrix protein functions between the different families within the negative-sense RNA viruses.
Topics: Arenaviridae; Borna disease virus; Bunyaviridae; Filoviridae; Models, Molecular; Orthomyxoviridae; Paramyxoviridae; Rhabdoviridae; Viral Matrix Proteins; Virion
PubMed: 23276954
DOI: 10.2741/4132 -
The Journal of General Virology Dec 2019The family consists of large enveloped RNA viruses infecting mammals, birds, reptiles and fish. Many paramyxoviruses are host-specific and several, such as measles...
The family consists of large enveloped RNA viruses infecting mammals, birds, reptiles and fish. Many paramyxoviruses are host-specific and several, such as measles virus, mumps virus, Nipah virus, Hendra virus and several parainfluenza viruses, are pathogenic for humans. The transmission of paramyxoviruses is horizontal, mainly through airborne routes; no vectors are known. This is a summary of the current International Committee on Taxonomy of Viruses (ICTV) Report on the family . which is available at ictv.global/report/paramyxoviridae.
Topics: DNA Barcoding, Taxonomic; Databases, Factual; Humans; Paramyxoviridae; Web Browser
PubMed: 31609197
DOI: 10.1099/jgv.0.001328 -
The Journal of General Virology Feb 2024is a family of negative-sense RNA viruses with genomes of about 13.1-20.9 kb that infect fish, mammals and reptiles. The filovirid genome is a linear, non-segmented...
is a family of negative-sense RNA viruses with genomes of about 13.1-20.9 kb that infect fish, mammals and reptiles. The filovirid genome is a linear, non-segmented RNA with five canonical open reading frames (ORFs) that encode a nucleoprotein (NP), a polymerase cofactor (VP35), a glycoprotein (GP), a transcriptional activator (VP30) and a large protein (L) containing an RNA-directed RNA polymerase (RdRP) domain. All filovirid genomes encode additional proteins that vary among genera. Several filovirids (e.g., Ebola virus, Marburg virus) are pathogenic for humans and highly virulent. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family , which is available at www.ictv.global/report/filoviridae.
Topics: Animals; Humans; Ebolavirus; Rhabdoviridae; Phylogeny; Marburgvirus; Genome, Viral; Virus Replication; Mammals
PubMed: 38305775
DOI: 10.1099/jgv.0.001955 -
Autophagy Oct 2023Ebola virus (EBOV) and Marburg virus (MARV) are zoonotic, virulent pathogens that cause sporadic and global outbreaks of severe hemorrhagic fever. Reemergence of these...
Ebola virus (EBOV) and Marburg virus (MARV) are zoonotic, virulent pathogens that cause sporadic and global outbreaks of severe hemorrhagic fever. Reemergence of these filoviruses remains a global public health threat, highlighting the need for novel countermeasures to control and treat future disease outbreaks. The EBOV VP40 matrix protein drives virion assembly and egress. We recently reported that BAG3 and HSPA/HSP70, two central components of chaperone-assisted selective autophagy (CASA), target VP40 for autophagic sequestration and degradation, thereby inhibiting virus egress and spread. In addition, we found that expression of the EBOV glycoprotein (GP) activates MTORC1, the gateway regulator of autophagy. Notably, pharmacological suppression of MTORC1 signaling by rapamycin activates autophagy and blocks filovirus egress. These findings highlight the MTORC1-CASA axis as a regulator of filovirus egress and suggest new opportunities for antiviral development and intervention.
Topics: Autophagy; Ebolavirus; Marburgvirus
PubMed: 36763514
DOI: 10.1080/15548627.2023.2178781 -
The Journal of Biological Chemistry Feb 2020Research in the last decade has uncovered many new paramyxoviruses, airborne agents that cause epidemic diseases in animals including humans. Most paramyxoviruses enter... (Review)
Review
Research in the last decade has uncovered many new paramyxoviruses, airborne agents that cause epidemic diseases in animals including humans. Most paramyxoviruses enter epithelial cells of the airway using sialic acid as a receptor and cause only mild disease. However, others cross the epithelial barrier and cause more severe disease. For some of these viruses, the host receptors have been identified, and the mechanisms of cell entry have been elucidated. The tetrameric attachment proteins of paramyxoviruses have vastly different binding affinities for their cognate receptors, which they contact through different binding surfaces. Nevertheless, all input signals are converted to the same output: conformational changes that trigger refolding of trimeric fusion proteins and membrane fusion. Experiments with selectively receptor-blinded viruses inoculated into their natural hosts have provided insights into tropism, identifying the cells and tissues that support growth and revealing the mechanisms of pathogenesis. These analyses also shed light on diabolically elegant mechanisms used by morbilliviruses, including the measles virus, to promote massive amplification within the host, followed by efficient aerosolization and rapid spread through host populations. In another paradigm of receptor-facilitated severe disease, henipaviruses, including Nipah and Hendra viruses, use different members of one protein family to cause zoonoses. Specific properties of different paramyxoviruses, like neurotoxicity and immunosuppression, are now understood in the light of receptor specificity. We propose that research on the specific receptors for several newly identified members of the family that may not bind sialic acid is needed to anticipate their zoonotic potential and to generate effective vaccines and antiviral compounds.
Topics: Animals; Humans; Membrane Fusion; Paramyxoviridae; Receptors, Virus; Tropism; Virus Attachment; Virus Internalization; Zoonoses
PubMed: 31949044
DOI: 10.1074/jbc.REV119.009961 -
Philosophical Transactions of the Royal... Sep 2013Bornaviruses are the only animal RNA viruses that establish a persistent infection in their host cell nucleus. Studies of bornaviruses have provided unique information... (Review)
Review
Bornaviruses are the only animal RNA viruses that establish a persistent infection in their host cell nucleus. Studies of bornaviruses have provided unique information about viral replication strategies and virus-host interactions. Although bornaviruses do not integrate into the host genome during their replication cycle, we and others have recently reported that there are DNA sequences derived from the mRNAs of ancient bornaviruses in the genomes of vertebrates, including humans, and these have been designated endogenous borna-like (EBL) elements. Therefore, bornaviruses have been interacting with their hosts as driving forces in the evolution of host genomes in a previously unexpected way. Studies of EBL elements have provided new models for virology, evolutionary biology and general cell biology. In this review, we summarize the data on EBL elements including what we have newly identified in eukaryotes genomes, and discuss the biological significance of EBL elements, with a focus on EBL nucleoprotein elements in mammalian genomes. Surprisingly, EBL elements were detected in the genomes of invertebrates, suggesting that the host range of bornaviruses may be much wider than previously thought. We also review our new data on non-retroviral integration of Borna disease virus.
Topics: Animals; Biological Evolution; Bornaviridae; Eukaryota; Genome; Humans; Mononegavirales Infections; Nucleoproteins; Virus Replication
PubMed: 23938751
DOI: 10.1098/rstb.2012.0499 -
Archives of Virology Dec 2020In March 2020, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was...
In March 2020, following the annual International Committee on Taxonomy of Viruses (ICTV) ratification vote on newly proposed taxa, the phylum Negarnaviricota was amended and emended. At the genus rank, 20 new genera were added, two were deleted, one was moved, and three were renamed. At the species rank, 160 species were added, four were deleted, ten were moved and renamed, and 30 species were renamed. This article presents the updated taxonomy of Negarnaviricota as now accepted by the ICTV.
Topics: Mononegavirales; Terminology as Topic
PubMed: 32888050
DOI: 10.1007/s00705-020-04731-2 -
Viruses Sep 2022The viral genus includes two highly virulent zoonotic viruses of serious public health concern. and outbreaks are restricted to Australia and Southeast Asia,...
The viral genus includes two highly virulent zoonotic viruses of serious public health concern. and outbreaks are restricted to Australia and Southeast Asia, respectively. The Henipavirus genus comprises mostly bat-borne viruses, but exceptions have already been described as novel viruses with rodents and shrews as reservoir animals. In the Americas, scarce evidence supports the circulation of these viruses. In this communication, we report a novel henipa-like virus from opossums () from a forest fragment area in the Peixe-Boi municipality, Brazil, after which the virus was named the Peixe-Boi virus (PBV). The application of next-generation sequencing and metagenomic approach led us to discover the original evidence of a henipa-like virus genome in Brazil and South America and the original description of a henipa-like virus in marsupial species. These findings emphasize the importance of further studies to characterize PBV and clarify its ecology, impact on public health, and its relationship with didelphid marsupials and henipaviruses.
Topics: Animals; Henipavirus Infections; Brazil; Hendra Virus; Nipah Virus; Genomics; Chiroptera
PubMed: 36298723
DOI: 10.3390/v14102167