Identification and characterization of the duck enteritis virus UL51 gene

Compared to the UL51 gene of other alphaherpesviruses, the duck enteritis virus (DEV) UL51 gene contains ten conserved motifs and has a close evolutionary relationship with members of the genus Mardivirus. The DEV UL51 gene product was identified using a rabbit polyclonal antiserum raised against a 6-His-UL51 fusion protein expressed in Escherichia coli as a 34-kDa protein. Western blotting and RT-(real time) PCR analysis of DEV-infected cells showed that the protein was produced at the late stage of infection and that its production was highly dependent on viral DNA synthesis, suggesting that the gene should be classified as gamma2 class. Analysis of extracellular virions revealed that the protein was a component of extracellular mature DEV virions. Indirect immunofluorescence studies localized most of the protein to the juxtanuclear region. These results will provide a basis for further functional analysis of the gene.