Mengovirus, also known as Columbia SK virus, mouse Elberfield virus and Encephalomyocarditisvirus (EMCV), belongs to the genus Cardiovirus

Cardiovirus

Cardiovirus is a genus within the family Picornaviridae. The genus comprises two species: Encephalomyocarditis virus and Theilovirus...

 which is a member of the Picornaviridae. Its genome is a single stranded positive-sense RNA

RNA

Ribonucleic acid , or RNA, is one of the three major macromolecules that are essential for all known forms of life....

 molecule, making the Mengoviruses a class IV virus

Virus classification

Virus classification is the process of naming viruses and placing them into a taxonomic system. Similar to the classification systems used for cellular organisms, virus classification is the subject of ongoing debate and proposals. This is mainly due to the pseudo-living nature of viruses, which...

 under the Baltimore classification

Baltimore classification

The Baltimore classification, developed by David Baltimore, is a virus classification system that groups viruses into families, depending on their type of genome and their method of replication....

 system. The genome is approximately 8400nt in length, and has 5’ VG protein (Virus genome protein) and a 3’ polyadenine tail.

Structure

The Mengovirus is a non-enveloped virus which has a nucleocapsid made up of 12 subunits. The virion is 30 nm in diameter and displays icosohedral symmetry.

Gene Expression and Genome Replication

Once inside a host cell, the Mengovirus genome acts as a piece of mRNA, and is directly translated by host ribosomes in the cytoplasm. There is a large un-translated region at the 5’ end of the RNA that has a ribosome binding site, removing the need of a cap. A single polypeptide is made, and is cleaved into individual proteins by viral proteases. The genome is divided into three parts: P1, P2 and P3. P1 encodes the virus capsid proteins, P2 and P3 encode genes required for genome replication to occur. For replication to occur an intermediate double stranded RNA molecule is made to be used as a template for the production of positive sense genomes.

Infection

Mengovirus is infectious to vertebrate animals, and has been isolated from mice and other rodents. It can also cause acute fever in humans. There is no specific treatment for a Mengovirus infection; although Persantine has been shown to inhibit its replication. The illness is not severe enough to require vaccination. The Mengovirus is able to suppress the host’s immune response by reducing the expression of Nuclear Factor kappa B using the 5’ un-translated region.

Further reading

• Rueckert RR (1990) Picornavirus and their multiplication. In: Fields BN, Knipe DM (eds) Virology, 2nd edn. Raven Press, New York, pp 507–548.
• Encephalomyocarditisvirus ICTVdB Index of Viruses, Version 28, June, 2002. Retrieved on 2007-07-15.
• Zoll et al., 2002, “The Mengovirus Leader Protein Suppresses Alpha/Beta Interferon Production by Inhibition of the Iron/Ferritin-Mediated Activation of NF- B”, Journal of Virology, 76, 19, 9664-9672.
• http://jvi.asm.org/cgi/content/full/79/17/11062?view=long&pmid=16103157 (this is the reference that is not working; please fix the problem if you can)