Caenorhabditis elegans is a free-living nematode (a roundworm), about 1 mm in length, which lives in a temperate soil environment. Researchers (Shou-Wei Ding, Morris Maduro and others) at the UC Riverside have discovered that this simple worm makes an excellent experimental host for studying some of the most virulent viruses that infect humans:):). The research is published in the journal Nature this month.

Caenorhabditis elegans (Courtesy: UC Riverside)For years researchers throughout the world have studied C. elegans because many aspects of its biology, such as genetics, development and the workings of neurons, mirror the biology of humans. However, no viruses were known to infect the millimeter-long roundworm so it was not used as a model for studying viral infections. The researchers have developed a strain of the worm, in which an animal virus could replicate, allowing them to map the delicate dance of action and reaction between virus and host:).
When a virus infects a living cell, it produces viral RNA, which allows the virus to replicate inside the host cell. When a virus infects the modified elegans worm however, the worm's DNA triggers an antiviral response known as RNA interference (RNAi). RNAi specifically breaks down the virus’ RNA:D. The virus responds by producing a protein acting as a suppressor of RNAi to shut down the host’s antiviral response:-SS. When the researchers introduced a mutation in the elegans genome that shuts down this virus protein generation, the worm did not get infected!!
By studying this interaction between the virus and the worm RNA/DNA, researchers are able to understand how the virus infection works:), as this process of infection has exact parallel in us humans! Viruses like Influenza and HIV are known to produce RNAi suppressors, and so by using the elegans to generate mutated genes, we might be one day able to conquer these days.
On a side-note, we are able to do all this, as we share a lot of our genome with even the lowliest of worms. Another hurrah for evolutionary theory:):).