University of Zurich researchers have revealed in a new study that viruses can travel around cells they infect through a microscopic transport system.
Cells are exposed to foreign DNA and RNA and it is understood that some of this genetic material can be integrated into the host genome.
Using modern microscopic techniques, scientists have been able to see how virus DNA is transported in the cell.
"We have been using human adenoviruses (Ads) to investigate transport processes of foreign DNA in the cytoplasm of human cells," said Professor Dr Urs Greber from the University of Zurich.
"Adenoviruses are a diverse family of agents that replicate their DNA genome in the cell nucleus. We wanted to find out how the virus gets to the nucleus to replicate. To do this we have been using live cell fluorescence microscopy, which means we can literally watch the virus travelling inside the cell," Greber said.
Human adenoviruses can cause respiratory, urinary and digestive infections. They occasionally cause epidemic conjunctivitis, and can be fatal in immunocompromised patients.
Adenoviruses can aggravate asthmatic conditions, and are associated with deadly gastroenteritis in babies. This research improves our knowledge of how the virus replicates in host cells.
"Virus DNA is transported from the edge of the cell to the nucleus in the middle by attaching to microtubules. These are microscopic tubes that form part of the cytoskeleton, keeping the cell in shape and carrying molecules around in the cytoplasm," said Professor Dr Greber.
"We found an unexpected new link between microtubule-based transport in the cytoplasm of the cell and the import of virus DNA to the nucleus," Dr. Greber added.