Structural organization of a conserved gene cluster of Tupaia herpesvirus encoding the DNA polymerase, glycoprotein B, a probable processing and transport protein, and the major DNA binding protein

The Tupaia herpesviruses (THVs) have been isolated from malignant lymphoma tissue cultures and from degenerating lung and spleen cell cultures of tree shrews (Tupaia spy.). Recently we succeeded in the localization of the gen e locus of the THV DNA polymerase (DPOL) gene within the viral genome. Base d on these results the highly conserved gene cluster of herpesviruses encod ing the DPOL, the glycoprotein B (gB), a probable processing and transport protein (PRTP), and the major DNA binding protein (DNBI) was characterized in the genome of THV strain 2 (THV-2) in its entirety. The complete nucleot ide sequence of the gene cluster was determined and it was discovered that the THV-2 gene products are most closely related to the corresponding prote ins of mammalian cytomegaloviruses. The transcriptional activity of the fou r genes was confirmed by amplification of a part of the corresponding mRNAs obtained from infected cell RNA by RT-PCR. The homology values and the ove rall structure of the gene cluster, that shows specific colinearity with th e corresponding clusters of the mammalian cytomegaloviruses, is further evi dence that THV-2 is a member of the subfamily Betaherpesvirinae. (C) 1999 E lsevier Science B.V. All rights reserved.