A research team in America may have come up with a potential treatment for Infectious salmon anaemia virus (ISAV) more commonly known as fish flu.
The team from the National Institute of Standards and Technology (NIST) have identified a genetic structure which may be responsible for triggering replication in the virus. At present the only way of treating the virus is by vaccination which is both tricky and economically impractical. If a method of disabling the virus reproduction is found, it will mean an end to the disease which currently claims mortality rates of up to 90% in fish farms.
Robert Brinson a NIST scientist together with his colleagues Andrea Szakal and John Marino identified a sequence of nucleotides known as a 'panhandle' structure in the ISAV RNA using high resolution nuclear magnetic resonance (NMR) spectroscopy. Previous studies have shown that similar structures in flu viruses interact with proteins involved in copying and replicating the viruses and it is thought that in the ISAV virus this ‘panhandle motif’ may act as a 'green light' for replication.
Brinson said: "The next step is to investigate the relevant proteins and how they interface with the RNA. What molecular features drive the protein to recognise the RNA? How is it binding, and how is it interacting with the RNA?"
The team hope that not only will their work help prevent the effects of the ISAV virus in salmon aquaculture but that it may also be used to understand human and other related influenza viruses.
The ISAV virus is highly contagious and found in Canada, Norway, Scotland and Chile and may lead to mortality rates of nearing 100% in some areas. Until recently the virus had only been reported in Atlantic salmon but in the last month Canadian scientists have reported a non-lethal strain in Pacific salmon which they fear will mutate and spread along the west coast.
For more information see: R. G. Brinson, A. L. Szakal, J. P. Marino. Structural Characterization of the Viral and Complementary RNA Panhandle Motifs from the Infectious Salmon Anemia Virus. Journal of Virology, 2011; DOI: 10.1128/JVI.06250-11
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