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Mengovirus, also known as Columbia SK virus, mouse Elberfield virus and Encephalomyocarditisvirus (EMCV), belongs to the genus Cardiovirus which is a member of the Picornaviridae. Its genome is a single stranded positive-sense RNA molecule, making the Mengoviruses a class IV virus under the Baltimore classification 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 an IRES (internal ribosome entry site) where the ribosome binds, removing the need of a cap. Rather than having a cap, the Mengovirus has a VPg protein bound to the 5' end of its positive strand RNA which acts as a primer for transcription as well as a subsitute for the 5' cap during initiation of translation. 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 mosquitoes and mice as well as other rodents. The virus infects its host using a fecal-oral route of infection. It can cause an 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.

Mengovirus Extraction
When using the Mengovirus for scientific research, such as to generate viral-specific proteins, Ehrlich ascites may be used as the host for the viral infection. Chromatography of Freon 113-extracted infected cells that had been concentrated with polyethyleneglycol from an aqueous phase on to a controlled pore glass (CPG) coated with protein can be used to extract Mengovirus. To purify the Mengovirus and concentrate it, an isopycnic density gradient can be used by centrifuging in either in a  CsCl solution or in a solution of iodinated benzoic acid  derived salts. This meathod is thought to be an exceptionally efficient way to extract large quantities of Mengovirus over a short period of time. Extraction kits may also be purchased. Once manufacturer of these is CEERAM which is distributed by Life Technologies. These kits include virus-specific primers and probes as well as the Mengovirus itself. The extraction kits use a recombinant strain of the virus, MC0. This strain is a non-enveloped, single-stranded RNA, non-pathogenic, culturable virus with similar properties to the hepatitis A virus. This strain does not naturally occur in the matrices used in the experiment because it acts in a distinctly resistant way when in the presence of target viruses.