Identification and characterization of the simian varicella virus uracil DNA glycosylase

Simian varicella virus (SVV) infection of non-human primates is used as a m odel to study the pathogenesis and latency of varicella-zoster virus (VZV), the etiological agent of chickenpox and shingles. Uracil DNA glycosylase ( UDG) is a DNA repair enzyme responsible for excision of uracil residues mis incorporated into DNA. UDG is conserved throughout the herpesvirus family a nd may play an important role in viral pathogenesis. This study identified a 300 amino acid SVV UDG that shares 53.9% amino acid identity with the VZV UDG. The SVV UDG is expressed in infected Vero cells as determined by reve rse transcriptase polymerase chain reaction (RT-PCR) and Northern blot anal ysis. The SVV UDG is encoded on a 2.0 kb transcript which also appears to e ncode the SVV glycoprotein L (gL) and the VZV gene 58 homolog. The SVV UDG is enzymatically active as determined by the ability of a SVV UDG-maltose b inding protein fusion construct to remove [H-3]-uracil incorporated into DN A.