ICP8, theherpes simplex virus type-1 single-strand DNA-binding protein, is one of sevenproteins encoded in theviralgenome ofHSV-1 that is required for HSV-1DNA replication.[1] It is able to anneal to single-stranded DNA (ssDNA) as well asmelt small fragments of double-stranded DNA (dsDNA);[1] its role is to destabilize duplex DNA during initiation of replication. It differs fromhelicases because it isATP- andMg2+-independent.[1] In cells infected with HSV-1, the DNA in those cells become colocalized with ICP8.
ICP8 is required in late genetranscription, and has found to be associated with cellularRNA polymerase II holoenzyme.[2]