Related Experiment Video
Updated: Jun 15, 2026
10:55
Vaccinia Virus Infection & Temporal Analysis of Virus Gene Expression: Part 2
Published on: April 10, 2009
The varicella-zoster virus genome
1Laboratory of Clinical Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA. jcohen@niaid.nih.gov
Current Topics in Microbiology and Immunology
|March 13, 2010
Summary
Varicella-zoster virus (VZV) gene knockouts reveal essential genes for in vitro growth. Recombinant VZV shows potential for developing new vaccines and serving as a vaccine vector.
Area of Science:
- Virology
- Molecular Biology
- Vaccinology
Background:
- The varicella-zoster virus (VZV) genome comprises over 70 genes, with most having homologs in herpes simplex virus (HSV).
- Understanding VZV gene function is crucial for vaccine development and therapeutic strategies.
Purpose of the Study:
- To identify essential VZV genes required for viral replication in vitro.
- To explore the potential of VZV as a vector for developing novel vaccines against VZV and other viral pathogens.
Main Methods:
- Utilized cosmids and BACs to generate gene knockouts for 34 VZV genes from parental and vaccine Oka strains.
- Constructed recombinant VZV expressing various reporter genes (e.g., beta-galactosidase, GFP, luciferase) and foreign viral genes.
Main Results:
- Identified seven VZV genes (ORF4, 5, 9, 21, 29, 62, and 68) essential for in vitro viral growth.
- Successfully created recombinant VZV expressing multiple markers and genes from diverse viruses, including HSV, EBV, HBV, mumps, HIV, and SIV.
Conclusions:
- Further investigation of the VZV genome using recombinant viruses can lead to safer and more effective VZV vaccines.
- VZV holds promise as a versatile vaccine vector for inducing immunity against VZV and other infectious agents.
Related Concept Videos
01:20Chickenpox
Chickenpox is an acute, highly contagious disease caused by the varicella-zoster virus (VZV), a double-stranded DNA virus belonging to the Herpesviridae family. Its transmission occurs primarily through the inhalation of respiratory droplets or direct contact with vesicular fluid from skin lesions. The incubation period typically ranges from 10 to 21 days, during which the virus replicates and disseminates through sequential phases within the host. Although generally self-limiting in children,...
01:26Size and Structure of Viral Genomes
Viral genomes exhibit remarkable diversity in size, structure, and composition, influencing their replication strategies and interactions with host cells. These genomes consist of either DNA or RNA and may be linear or circular. Additionally, they can be single-stranded or double-stranded, with each configuration affecting how the virus propagates within a host. RNA viruses, for instance, generally have smaller genomes than DNA viruses, a factor that contributes to their high mutation rates and...
00:56Viral Structure
Viruses are extraordinarily diverse in shape and size, but they all have several structural features in common. All viruses have a core that contains a DNA- or RNA-based genome. The core is surrounded by a protective coat of proteins called the capsid. The capsid is composed of subunits called capsomeres. The capsid and genome-containing core are together known as the nucleocapsid.
02:33Retroviruses
Retroviruses and retrotransposons both insert copies of their genetic elements into the genome of the host cell. Thus, the viral genes are passed on when the host genome is replicated or translated. A typical retroviral DNA sequence contains 3-4 genes that encode the different proteins required for its structural assembly and function as a molecular parasite. This DNA is transcribed into a single mRNA, which is very similar in structure to conventional mRNAs, i.e., it is capped at the 5’...
01:03Rous Sarcoma Virus (RSV) and Cancer
Rous Sarcoma virus or RSV was discovered by F. Peyton Rous in the year 1911 as a filterable transmissible agent that could cause tumors in chickens. He won a Nobel Prize for this discovery in 1966. His experiments clearly demonstrated that some cancers could be caused by infectious agents and led to the discovery of many more cancer-causing viruses in animals as well as humans.
RSV is a retrovirus that contains two copies of a plus-strand RNA genome. Its genome consists of four main open...
RSV is a retrovirus that contains two copies of a plus-strand RNA genome. Its genome consists of four main open...
01:29Viruses with RNA Genomes
RNA viruses are categorized into positive-strand, negative-strand, or double-stranded groups based on their genomic structure and replication mechanisms. This classification dictates how they exploit host cellular machinery for protein synthesis and replication. Some RNA viruses also utilize reverse transcription as part of their life cycle, further diversifying their replication strategies.Positive-Strand RNA VirusesPositive-strand RNA viruses have genomes that function directly as messenger...