Mardivirus

Mardivirus is a recently established genus within the Alphaherpesvirinae subfamily. It is made up of the Marek's disease virus (MDV), which causes a lymphoproliferative disease in chickens, and two other closely related viruses including gallid herpesvirus 3 (GaHV-3 also known as MDV-2) and the herpesvirus of turkeys (HVT). MDV is the only one of these viruses known to be pathogenic and due to the antigenic similarity between the three viruses the other two have been used to vaccinate against Marek’s disease. These viruses have double stranded DNA genomes with no RNA intermediate.

Replication
The stages of replication are similar to other viruses in this subfamily, but there are a few differences. After the virus has entered the cell the nucleocapsids make their way to a nuclear pore where the virus genome is released and translocates into the nucleus. The virus genome replicates and is packaged up within the nucleus, this new nucleocapsid then buds from the inner nuclear membrane and so gains its primary envelope. The nucleocapsid is now in the perinuclear space in the endoplasmic reticulum, from here the nucleocapsid buds from the outer nuclear membrane and by an unknown mechanism loses its primary envelope leaving the nucleocapsid naked in the cytoplasm. The nucleocapsids finally gain their secondary envelopes by budding into cytoplasmic vesicles within the cell.