Novel simian homologues of Epstein-Barr virus

Abstract

Thirty different lymphocryptoviruses (LCV), 26 of them novel, were detected in primates by a panherpesvirus PCR assay. Nineteen LCV from chimpanzees, bonobos, gorillas, and other Old World primates were closely related to Epstein-Barr virus (EBV), the type species of the genus lymphocryptovirus. Seven LCV originating from New World primates were related to callitrichine herpesvirus 3 (CalHV-3), the first recognized New World LCV. Importantly, a second LCV from gorillas and three LCV from orangutans and gibbons were only distantly related to EBV and CalHV-3. They were tentatively assigned to a novel genogroup of Old World primate LCV. The work described in the paper may also help identify an as yet unknown human LCV.

FIG. 1.

Schematic diagram of the PCR strategy. (a) Initial panherpesvirus nested PCR with degenerate and deoxyinosine-substituted primers, used for amplification of novel herpesvirus DPOL gene sequences. (b) Subsequent heminested PCR with the degenerate sense primer DFA and two virus-specific antisense primers. (c and d) Alternative heminested PCR approaches with a pan-LCV sense primer (1743s or 1828s) and two virus-specific antisense primers. The partial DPOL gene of EBV is shown at the top for demonstration of the primer binding regions. The positions bp 1226 and 2489 refer to the 5′ ends of the binding regions of the primers 1828s and KG1, respectively. Solid arrowheads, degenerate primers; open arrowheads, specific primers. The virus-specific antisense primers have slightly different positions in each individual DPOL gene sequence, but they are always located between primers TGV and IYG.

FIG. 2.

Phylogenetic analysis of novel LCV. A maximum-likelihood tree was constructed for the novel DPOL gene sequences listed in Table 1 and DPOL gene sequences of LCV available in GenBank (accession numbers are given in the text). Primate rhadinoviruses (RHV) were also included (PtroRHV, Pan troglodytes RHV; accession no. AF250879; GgorRHV, Gorilla gorilla RHV; accession no. Af250886). Sequences of 435 bp were aligned with ClustalW. The multiple alignment (with gaps removed) was analyzed with the TREE-PUZZLE, version 5.0, program. A rooted phylogram is shown, with HHV-8 as the outgroup. Support values >50% are indicated at the nodes of the tree. RHV, Old World primate LCV (genogroups I and II), and New World primate LCV are indicated. LCV virus abbreviations are defined in Table 1.