Related Experiment Video

Updated: Aug 25, 2026

Preparation of rAAV9 to Overexpress or Knockdown Genes in Mouse Hearts
11:11

Preparation of rAAV9 to Overexpress or Knockdown Genes in Mouse Hearts

Published on: December 17, 2016

Role of viral vectors and virion shells in cellular gene expression

Jackie L Stilwell1, Richard Jude Samulski

  • 1Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7352, USA.

Molecular Therapy : the Journal of the American Society of Gene Therapy
|March 10, 2004
PubMed

Insights

Viral capsids significantly influence gene expression and host toxicity. Understanding capsid effects independent of the genome is crucial for safe gene therapy development using viral vectors.

Area of Science:

  • Virology
  • Molecular Biology
  • Gene Therapy

Background:

  • The role of viral shells (capsids) in disease is not well understood.
  • Viral vectors are used in gene therapy, necessitating knowledge of capsid-host interactions.

Purpose of the Study:

  • To investigate how viral capsids from pathogenic adenovirus and nonpathogenic adeno-associated virus affect cellular gene expression.
  • To compare the responses to intact viruses, recombinant vectors, and empty viral particles.

Main Methods:

  • Utilized DNA microarrays to identify gene expression changes during viral infections.
  • Compared cellular responses to wild-type viruses, engineered vectors, and empty capsids.

Main Results:

  • Adeno-associated virus capsids induced a nonpathogenic gene expression profile, including antiproliferative genes.
  • Adenovirus capsids triggered a broader response, with immune and stress-response genes linked to pathogenicity.
  • Empty capsids from both viruses elicited distinct gene expression patterns.

Conclusions:

  • Viral capsids independently impact cellular gene expression and can cause host toxicity.
  • Capsid-mediated effects must be assessed separately from the vector genome for safe clinical gene transfer.

More Related Videos

Transgene Expression in Cultured Cells Using Unpurified Recombinant Adeno-Associated Viral Vectors06:41

Transgene Expression in Cultured Cells Using Unpurified Recombinant Adeno-Associated Viral Vectors

Published on: October 20, 2023

Related Concept Videos

Introduction to Virus01:28

Introduction to Virus

Viruses are unique biological entities that blur the boundary between living and non-living systems. Although they lack cellular structure and metabolic processes, they can exhibit characteristics of life when infecting a host. Their defining feature is a nucleic acid core, composed of either DNA or RNA, encapsulated within a protein coat called a capsid. This simple structure allows them to invade host cells and use their machinery for replication efficiently.Viral Structure and...
Viral Structure00:56

Viral 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.
Viruses with RNA Genomes01:29

Viruses 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...
Retroviruses02:33

Retroviruses

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’...
Retrovirus Life Cycles01:10

Retrovirus Life Cycles

Retroviruses have a single-stranded RNA genome that undergoes a special form of replication. Once the retrovirus has entered the host cell, an enzyme called reverse transcriptase synthesizes double-stranded DNA from the retroviral RNA genome. This DNA copy of the genome is then integrated into the host’s genome inside the nucleus via an enzyme called integrase. Consequently, the retroviral genome is transcribed into RNA whenever the host’s genome is transcribed, allowing the retrovirus to...
Size and Structure of Viral Genomes01:26

Size 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...