Document text
Principal Investigator: Z Hong ZHOU
Organization: UNIVERSITY OF CALIFORNIA LOS ANGELES
Fiscal Year: 2023
Award: $31,788
Funding agency: National Institute of Allergy and Infectious Diseases
PROJECT SUMMARY/ABSTRACT
Double-stranded RNA (dsRNA) viruses comprise a large group of non-enveloped viruses characterized by
their ability to transcribe their RNA within an intact capsid (i.e., endogenous RNA transcription), thus evading
cellular antiviral responses to dsRNA. Among them, members of the Reoviridae family of dsRNA viruses are of
significance in both public health and basic science, exemplified respectively by the gastroenteritis-causing
rotavirus which is responsible for approximately half a million child deaths annually worldwide and the insect-
killing cytoplasmic polyhedrosis virus (CPV) which was used historically as a model in the discovery of RNA
capping. We have studied non-enveloped dsRNA viruses with single-layered (CPV), double-layered
[mammalian reovirus (MRV) and aquareovirus (ARV)], and triple-layered [rhesus rotavirus (RRV), Bluetongue
virus (BTV)] capsid. These viruses could also be classified based on the presence (such as CPV and
reoviruses) or absence (such as BTV and RRV) of an mRNA-capping turret on the icosahedral vertices of their
innermost shell. Results from the prior funding cycles have uncovered that BTV and CPV both use surface
trimers bearing similarities to fusion proteins of enveloped viruses (e.g., flu, AIDS and COVID-19 viruses) for
cell entry. We have also captured the asymmetrically attached transcriptional enzyme complex (TEC) at the
quiescent, initiation and transcribing stages of CPV, BTV and RRV; and identified both conserved and diverse
features among their structures and organizations of TEC and RNA capping. Our studies showed that, upon
cell entry, these viruses sense different environmental cues for internal transcription activation; and in the case
of CPV, sensing of SAM and ATP by the RNA-capping turret triggers a cascade of events: opening of the turret
iris, detachment of the trimeric spike, and initiation of endogenous transcription.
The need to conserve endogenous RNA transcription and the structural diversities uncovered in our prior
studies have led to our overall hypothesis: genomes of dsRNA viruses have diverged substantially to allow
incorporation of RNA segments encoding the distinct proteins required to interact with different host cells,
giving rise to different genome and TEC organizations and variations to both RNA unwinding during
transcription and RNA capping during release. The goal of this renewal application is to test this hypothesis
with state-of-the-art cryogenic electron microscopy (cryoEM) and tomography (cryoET) by determining
representative dsRNA viruses’ genome organizations during quiescence, unwinding and capping during
transcription, and genome packing during assembly. We will model the genomes inside CPV, BTV, as well as
dsRNA viruses with one and two dsRNA segments for comparison (Aim 1). Capping and cap-snatching during
RNA transcription will then be investigated (Aim 2). Finally, we will visualize how different genomic RNA and
capsid proteins assemble to form infectious virion particles (Aim 3). As demonstrated in our prior work, these
studies will be complemented by structure-based mutagenesis for functional verification.
Terms: <0-11 years old><2019 novel corona virus><2019 novel coronavirus><2019-nCoV><5' Capped RNA><5' mRNA Cap Structure><AIDS Virus><Academia><Acquired Immune Deficiency Syndrome Virus><Acquired Immunodeficiency Syndrome Virus><Airway infections><Animals><Anti-Viral Response><Antiviral Response><Antiviral Therapy><Aqua reovirus><Aquareoviruses><Aquatic Reovirus><Area><Award><Bacteria><Baculovirus Expression System><Basic Research><Basic Science><Binding Proteins><Blue Tongue Virus><Bluetongue virus><COVID-19 virus><COVID19 virus><Capsid><Capsid Proteins><Cell Body><Cells><Cessation of life><Child><Child Youth><Children (0-21)><Chimera Protein><Chimeric Proteins><Classification><Clinical Trials><CoV-2><CoV2><Coat Proteins><Complement><Complement Proteins><Cryo-electron Microscopy><Cryoelectron Microscopy><Cues><Cytoplasmic Polyhedrosis Viruses><Death><Detection><Development><Diarrhea><Double Stranded RNA Virus><Double-Stranded RNA><Drug Delivery><Drug Delivery Systems><Economics><Electron Cryomicroscopy><Electrons><Engineering><Event><Family><Farm Animal><Fellowship><Flu virus><Funding><Fusion Protein><Future><Gastroenteritis><Gene Transcription><Genetic Transcription><Genetics-Mutagenesis><Genome><Goals><HIV><Health Sciences><Human><Human Immunodeficiency Viruses><Insecta><Insects><Insects Invertebrates><Intestinal><Intestines><Investigation><Investigators><Ions><Iris><LAV-HTLV-III><Life><Ligand Binding Protein><Ligand Binding Protein Gene><Livestock><Lymphadenopathy-Associated Virus><Modeling><Modern Man><Multienzyme Complexes><Mutagenesis><Mutagenesis Molecular Biology><Negative Beta Particle><Negatrons><Non-Polyadenylated RNA><Oncolytic><Outcome><Ovine Catarrhal Fever Virus><Pathogenicity><Pathway interactions><Phase><Plants><Position><Positioning Attribute><Postdoc><Postdoctoral Fellow><Principal Investigator><Protein Binding><Proteins><Public Health><RNA><RNA Caps><RNA Expression><RNA Gene Products><Recombinants><Reoviridae><Reovirus><Reovirus 3><Reovirus Type 1><Reovirus Type 3><Research><Research Associate><Research Personnel><Researchers><Resolution><Respiratory Enteric Orphan Viruses><Respiratory Infections><Respiratory Tract Infections><Rhesus><Ribonucleic Acid><Rotavirus><Rotavirus Vaccines><SARS corona virus 2><SARS-CO-V2><SARS-COVID-2><SARS-CoV-2><SARS-CoV2><SARS-associated corona virus 2><SARS-associated coronavirus 2><SARS-coronavirus-2><SARS-related corona virus 2><SARS-related coronavirus 2><SARSCoV2><Science><Severe Acute Respiratory Coronavirus 2><Severe Acute Respiratory Distress Syndrome CoV 2><Severe Acute Respiratory Distress Syndrome Corona Virus 2><Severe Acute Respiratory Distress Syndrome Coronavirus 2><Severe Acute Respiratory Syndrome CoV 2><Severe Acute Respiratory Syndrome-associated coronavirus 2><Severe Acute Respiratory Syndrome-related coronavirus 2><Severe acute respiratory syndrome associated corona virus 2><Severe acute respiratory syndrome coronavirus 2><Severe acute respiratory syndrome related corona virus 2><Structure><Study models><Surface><Systematics><Technology><Testing><Transcription><Transcription Activation><Transcriptional Activation><Vaccines><Variant><Variation><Viral Coat Proteins><Viral Gene Products><Viral Gene Proteins><Viral Genome><Viral Outer Coat Protein><Viral Proteins><Virion><Virus><Virus Assembly><Virus Particle><Virus-HIV><Virus-like particle><Visualization><Work><Wuhan coronavirus><anti-viral development><anti-viral drug development><anti-viral therapeutic development><anti-viral therapy><anti-viral therapy development><antiviral development><antiviral drug development><antiviral therapeutic development><antiviral therapy development><bound protein><bowel><career><coronavirus disease 2019 virus><coronavirus disease-19 virus><cryo-EM><cryoEM><cryogenic electron microscopy><cytoplasmic polyhedrosis virus><deliver vaccines><develop a vaccine><develop vaccines><developing anti-viral agent><developing anti-viral drug><developing anti-viral therapeutic><developing anti-viral therapy><developing antiviral agent><developing antiviral drug><developing antiviral therapeutic><developing antiviral therapy><development of a vaccine><developmental><dsRNA><dsRNA Virus><echovirus 10><economic><electron tomography><enteral infection><enteric infection><enteric pathogen infection><enteropathogen infection><enteropathogenic infection><enzyme complex><fungus><genomic RNA><hCoV19><human pathogen><immunogenic><improved><infected with enteropathogen><insight><intestinal infection><intestine infection><kids><mRNA capping><member><nCoV2><nano particle delivery><nanocarrier><nanoparticle delivered><nanoparticle delivery><nanovessel><parent grant><particle><pathogen><pathway><post-doc><post-doctoral><post-doctoral trainee><pre-doc><pre-doctoral><predoctoral><receptor binding><receptor bound><reovirus 1><research associates><resolutions><self assembly><social><structural biology><vaccine delivery><vaccine development><viral assembly><viral infectious disease treatment><virus genome><virus protein><virus-like nanoparticles><viruslike particle><youngster>