Faculty Opinions recommendation of Membrane anchors of the structural flavivirus proteins and their role in virus assembly.

2016 ◽  
Author(s):  
Anne Moscona ◽  
Laura M Palermo
Keyword(s):  
Virus Assembly

Involvement of GER in Friend leukemia virus assembly in high-pressure frozen cells

1990 ◽  
Vol 48 (3) ◽  
pp. 590-591
Author(s):  
W. Djaczenko ◽  
M. Müller ◽  
A. Benedetto ◽  
G. Carbone
Keyword(s):  
High Pressure ◽  
Virus Assembly ◽  
Leukemia Virus ◽  
Leukemia Cells ◽  
Serial Sections ◽  
Myeloma Cells ◽  
Virus Particles ◽  
Friend Leukemia ◽  
Carbon Coated ◽  
Friend Leukemia Virus

A thickening of ER membranes in murine myeloma cells was attributed by de Harven to the assembly of intracisternal virus particles. We observed similar thickening of GER membranes in Friend leukemia cells (FLC) apparently associated with Friend leukemia virus (FLV) assembly. We reinvestigated the problem of GER involvement in FLV assembly using high pressure cryofixed FLC.FLC (745A clone growing in suspension and FF clone growing in monolayer) were immersed in Hexadecene (Fluka, Switzerland) and rapidly frozen in Balzers HPM 010 freezing machine working at 2200 bar. All cells were freeze substituted at -90°C in 2% OsO4 in absolute acetone. Serial sections cut to avoid misinterpretations due to the geometry of sections, were collected on carbon coated 100 mesh grids.

scholarly journals Flavivirus NS1 and Its Potential in Vaccine Development

Vaccines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 622
Author(s):  
Kassandra L. Carpio ◽  
Alan D. T. Barrett
Keyword(s):  
Vaccine Development ◽  
Virus Assembly ◽  
Ns1 Protein ◽  
Human Pathogens ◽  
Unusual Structure ◽  
Replication Complex ◽  
Virus Challenge ◽  
Humoral Immune ◽  
Tick Borne Encephalitis ◽  
Flavivirus Infection

The Flavivirus genus contains many important human pathogens, including dengue, Japanese encephalitis (JE), tick-borne encephalitis (TBE), West Nile (WN), yellow fever (YF) and Zika (ZIK) viruses. While there are effective vaccines for a few flavivirus diseases (JE, TBE and YF), the majority do not have vaccines, including WN and ZIK. The flavivirus nonstructural 1 (NS1) protein has an unusual structure–function because it is glycosylated and forms different structures to facilitate different roles intracellularly and extracellularly, including roles in the replication complex, assisting in virus assembly, and complement antagonism. It also plays a role in protective immunity through antibody-mediated cellular cytotoxicity, and anti-NS1 antibodies elicit passive protection in animal models against a virus challenge. Historically, NS1 has been used as a diagnostic marker for the flavivirus infection due to its complement fixing properties and specificity. Its role in disease pathogenesis, and the strong humoral immune response resulting from infection, makes NS1 an excellent target for inclusion in candidate flavivirus vaccines.

scholarly journals Aptamer Applications in Emerging Viral Diseases

2021 ◽  
Vol 14 (7) ◽  
pp. 622
Author(s):  
Arne Krüger ◽  
Ana Paula de Jesus Santos ◽  
Vanessa de Sá ◽  
Henning Ulrich ◽  
Carsten Wrenger
Keyword(s):  
Virus Assembly ◽  
Viral Diseases ◽  
Tissue Penetration ◽  
Rna Molecules ◽  
Viral Particles ◽  
Pharmacokinetic Properties ◽  
Oligonucleotide Library ◽  
In Vivo Diagnosis ◽  
Emerging Viral Diseases

Aptamers are single-stranded DNA or RNA molecules which are submitted to a process denominated SELEX. SELEX uses reiterative screening of a random oligonucleotide library to identify high-affinity binders to a chosen target, which may be a peptide, protein, or entire cells or viral particles. Aptamers can rival antibodies in target recognition, and benefit from their non-proteic nature, ease of modification, increased stability, and pharmacokinetic properties. This turns them into ideal candidates for diagnostic as well as therapeutic applications. Here, we review the recent accomplishments in the development of aptamers targeting emerging viral diseases, with emphasis on recent findings of aptamers binding to coronaviruses. We focus on aptamer development for diagnosis, including biosensors, in addition to aptamer modifications for stabilization in body fluids and tissue penetration. Such aptamers are aimed at in vivo diagnosis and treatment, such as quantification of viral load and blocking host cell invasion, virus assembly, or replication, respectively. Although there are currently no in vivo applications of aptamers in combating viral diseases, such strategies are promising for therapy development in the future.

scholarly journals Norwalk Virus Assembly and Stability Monitored by Mass Spectrometry

2010 ◽  
Vol 9 (8) ◽  
pp. 1742-1751 ◽  
Author(s):  
Glen K. Shoemaker ◽  
Esther van Duijn ◽  
Sue E. Crawford ◽  
Charlotte Uetrecht ◽  
Marian Baclayon ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Virus Assembly ◽  
Norwalk Virus

scholarly journals Specific Recognition of a Stem-Loop RNA Structure by the Alphavirus Capsid Protein

Viruses ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1517
Author(s):  
Rebecca S. Brown ◽  
Lisa Kim ◽  
Margaret Kielian
Keyword(s):  
Capsid Protein ◽  
Rna Structure ◽  
Semliki Forest Virus ◽  
Virus Assembly ◽  
Specific Binding ◽  
Genomic Rna ◽  
Stem Loop ◽  
Stem Loop Structure ◽  
Labeled Rna

Alphaviruses are small enveloped viruses with positive-sense RNA genomes. During infection, the alphavirus capsid protein (Cp) selectively packages and assembles with the viral genomic RNA to form the nucleocapsid core, a process critical to the production of infectious virus. Prior studies of the alphavirus Semliki Forest virus (SFV) showed that packaging and assembly are promoted by Cp binding to multiple high affinity sites on the genomic RNA. Here, we developed an in vitro Cp binding assay based on fluorescently labeled RNA oligos. We used this assay to explore the RNA sequence and structure requirements for Cp binding to site #1, the top binding site identified on the genomic RNA during all stages of virus assembly. Our results identify a stem-loop structure that promotes specific binding of the SFV Cp to site #1 RNA. This structure is also recognized by the Cps of the related alphaviruses chikungunya virus and Ross River virus.

scholarly journals Cellular Determinants of Hepatitis C Virus Assembly, Maturation, Degradation, and Secretion

2007 ◽  
Vol 82 (5) ◽  
pp. 2120-2129 ◽  
Author(s):  
Pablo Gastaminza ◽  
Guofeng Cheng ◽  
Stefan Wieland ◽  
Jin Zhong ◽  
Wei Liao ◽  
...  
Keyword(s):  
Hepatitis C Virus ◽  
Hepatitis C ◽  
Virus Assembly ◽  
Buoyant Density ◽  
Infectious Hepatitis ◽  
Low Density ◽  
Very Low Density Lipoproteins ◽  
Independent Manner ◽  
Viral Egress ◽  
Vldl Assembly

ABSTRACT Intracellular infectious hepatitis C virus (HCV) particles display a distinctly higher buoyant density than do secreted virus particles, suggesting that the characteristic low density of extracellular HCV particles is acquired during viral egress. We took advantage of this difference to examine the determinants of assembly, maturation, degradation, and egress of infectious HCV particles. The results demonstrate that HCV assembly and maturation occur in the endoplasmic reticulum (ER) and post-ER compartments, respectively, and that both depend on microsomal transfer protein and apolipoprotein B, in a manner that parallels the formation of very-low-density lipoproteins (VLDL). In addition, they illustrate that only low-density particles are efficiently secreted and that immature particles are actively degraded, in a proteasome-independent manner, in a post-ER compartment of the cell. These results suggest that by coopting the VLDL assembly, maturation, degradation, and secretory machinery of the cell, HCV acquires its hepatocyte tropism and, by mimicry, its tendency to persist.

scholarly journals Mutation of Dileucine-Like Motifs in the Human Immunodeficiency Virus Type 1 Capsid Disrupts Virus Assembly, Gag-Gag Interactions, Gag-Membrane Binding, and Virion Maturation

2006 ◽  
Vol 80 (16) ◽  
pp. 7939-7951 ◽  
Author(s):  
Anjali Joshi ◽  
Kunio Nagashima ◽  
Eric O. Freed
Keyword(s):  
Human Immunodeficiency Virus ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
Particle Production ◽  
Virus Assembly ◽  
Membrane Binding ◽  
Single Amino Acid ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT The human immunodeficiency virus type 1 (HIV-1) Gag precursor protein Pr55Gag drives the assembly and release of virus-like particles in the infected cell. The capsid (CA) domain of Gag plays an important role in these processes by promoting Gag-Gag interactions during assembly. The C-terminal domain (CTD) of CA contains two dileucine-like motifs (L189/L190 and I201/L202) implicated in regulating the localization of Gag to multivesicular bodies (MVBs). These dileucine-like motifs are located in the vicinity of the CTD dimer interface, a region of CA critical for Gag-Gag interactions during virus assembly and CA-CA interactions during core formation. To study the importance of the CA dileucine-like motifs in various aspects of HIV-1 replication, we introduced a series of mutations into these motifs in the context of a full-length, infectious HIV-1 molecular clone. CA mutants LL189,190AA and IL201,202AA were both severely impaired in virus particle production because of a variety of defects in the binding of Gag to membrane, Gag multimerization, and CA folding. In contrast to the model suggesting that the CA dileucine-like motifs regulate MVB targeting, the IL201,202AA mutation did not alter Gag localization to the MVB in either HeLa cells or macrophages. Revertants of single-amino-acid substitution mutants were obtained that no longer contained dileucine-like motifs but were nevertheless fully replication competent. The varied phenotypes of the mutants reported here provide novel insights into the interplay among Gag multimerization, membrane binding, virus assembly, CA dimerization, particle maturation, and virion infectivity.

Sign in / Sign up

Export Citation Format

Share Document