Scientists have modified an influenza virus so that it can infect fruit flies, enabling them to identify over 100 new ways to fight flu in future.
Writing in this weeks Nature, Howard Hughes Medical Institute researcher Paul Ahlquist and his colleagues describe how, by replacing the outer coat of the flu virus with proteins from a different virus that can infect fly cells, they were able to produce a form of fly flu. The team infected fly cells with this viral variant and then used a technique called RNA interference to selectively switch off each of the fly cells' 13,000 genes, one at a time, to identify those which are essential for the virus to grow. The analysis flushed out over 100 cellular genes, which have direct equivalents in mammalian cells like our own, that the virus depends upon for growth.
To confirm that the results would be relevant to normal strains of flu the team then tested the ability of natural strains to infect mammalian cells lacking three of the genes uncovered by the fly cell tests. They found that suppressing the function of any of the three genes, known as ATP6V0D1, COX6A1 and NXF1, prevented flu viruses, including the pandemic contender H5N1, from replicating, suggesting that the 100 genes they've identified are likely to highlight many novel therapeutic strategies for swatting the flu in future.