Protein Domain : Chicken anaemia virus VP-3 protein IPR006858

Type	Family
Description	Chicken anaemia virus (CAV) is a circovirus which can cause severe depletion of some cell types, such as lymphocytes, by the induction of apoptosis [ ]. Studies indicate that expression of the viral VP3 protein, also known as apoptin, is sufficient to induce apoptosis in susceptible cells and to produce the doughnut-shaped apoptosis body formations observed in cells during CAV infections. This protein induces apoptosis in tumor cells and transformed cells, but is incapable of inducing apoptosis in normal cells unless tranforming signals are supplied which induce its phosphorylation. Cell death occurs in a p53- and Bcl-2-independent manner []. Apoptin contains putative nuclear localisation and nuclear export domains, and has a positively charged C terminus which is thought to allow direct interaction with nucleic acids. Localisation to the nucleus appears to be necessary for apoptosis, but is not sufficient on its own. The biologically active form of the protein appears to be large complexes of 30-40 molecules which form distinct superstructures upon DNA binding. A number of cellular factors including Nmi, and several death domain superfamily proteins, have been shown to interact apoptin. It has been suggested that in the nucleus, it this binding of phosphorylated apoptin to DNA and other factors which starts the apoptotic machinery, triggering cell death.
Short Name	CAV_VP3