Researchers at The Pirbright Institute and the University of Glasgow have identified structures in the foot-and-mouth disease virus (FMDV) genome that are involved in packaging the genome into the viral capsid.
In picornaviruses, such as FMDV and poliovirus, the viral genetic code is contained in a long molecule of RNA packaged within a protein shell called a capsid. The capsid protects the RNA and allows the virus to spread between cells and be transmitted between hosts. The process for how the RNA molecule is correctly packaged into the capsid has been a mystery for many years. The identification of sequences required for this process is the first step in understanding how packaging works, and may lead to novel approaches to virus prevention.
Dr Grace Logan at Pirbright used genetic sequencing to identify regions in packaged FMDV RNA different to those in unpackaged RNA and therefore might be involved in its packaging into the capsid shell. Using bioinformatics analysis, they discovered these regions in the packaged RNA had the ability to form lollipop shaped structures to promote packaging. Dr Joseph Newman then demonstrated by disrupting these structures prevented the growth of FMDV in cell cultures and its ability to assemble new viruses efficiently. The research, published in The Journal of Virology, suggests such structures are important for the packaging of RNA into the capsid.
FMD has a huge social and economic impact worldwide. In developing countries livestock provide food security, transport and power for cultivating land and FMD prevents economic development in rural communities. In FMD free countries, an outbreak can cause significant losses such as the 2001 outbreak which cost the UK economy £8 billion.
This study was funded by the Biotechnology and Biological Sciences Research Council (BBSRC) (Grant numbers BBS/E/I/00001756, BB/L004828/1, and BB/K003801/1).