Genetic and ultrastructural characterization of a European isolate of the fatal endotheliotropic elephant herpesvirus

Abstract

A male Asian elephant (Elephas maximus) died at the Berlin zoological gardens in August 1998 of systemic infection with the novel endotheliotropic elephant herpesvirus (ElHV-1). This virus causes a fatal haemorrhagic disease in Asian elephants, the so-called endothelial inclusion body disease, as reported from North American zoological gardens. In the present work, ElHV-1 was visualized ultrastructurally in affected organ material. Furthermore, a gene block comprising the complete glycoprotein B (gB) and DNA polymerase (DPOL) genes as well as two partial genes was amplified by PCR-based genome walking and sequenced. The gene content and arrangement were similar to those of members of the Betaherpesvirinae. However, phylogenetic analysis with gB and DPOL consistently revealed a very distant relationship to the betaherpesviruses. Therefore, ElHV-1 may be a member of a new genus or even a new herpesvirus subfamily. The sequence information generated was used to set up a nested-PCR assay for diagnosis of suspected cases of endothelial inclusion body disease. Furthermore, it will aid in the development of antibody-based detection methods and of vaccination strategies against this fatal herpesvirus infection in the endangered Asian elephant.

Association of Two Newly Recognized Herpesviruses with Interstitial Pneumonia in Donkeys (Equus Asinus)

“…6), as has been demonstrated by others using similar phylogenetic methodologies. 13,14,23,37,43 Inclusion of AHV4-, AHV5-, and AHV5a-deduced amino acid sequences in this phylogenetic analysis demonstrated that these viruses are members of the Gammaherpesvirinae subfamily and that AHV4, AHV5, and AHV5a are distinct from, but most closely related to, other gammaherpesviruses of equids. * Represents the mean of identity values from AHV4-1, -2, -3.…”

“…Recently, others have used PCR amplification of the highly conserved DNA polymerase gene as a means of detecting novel members of the Herpesviridae family in diseased tissue. 8,[12][13][14]21,22,31,34,37 The ability to perform PCR amplification of pathogens from formalin-fixed, paraffin-embedded tissues 10,17,18,26,42 has provided the opportunity to retrospectively examine samples from cases with similar lesions. In the present study, DNA was extracted and herpesvirus DNA was successfully amplified from formalin-fixed, paraffin-embedded tissue blocks that had been held under ambient conditions for up to 6 years.…”

Characterization of the Betaherpesviral pUL69 Protein Family Reveals Binding of the Cellular mRNA Export Factor UAP56 as a Prerequisite for Stimulation of Nuclear mRNA Export and for Efficient Viral Replication

“…The sequences of all primers are listed in Table 1. Expression constructs for betaherpesviral pUL69 homologs CCMV pC69 (GenBank accession number AF480884; gi 19881028) (13), RhCMV pRh69 (GenBank accession number AY186194; gi 31377878) (21), MCMV pM69 (GenBank accession number U68299; gi 1688100) (37), HHV6A pU42 (GenBank accession number X92436; gi 1044869) (18), and ElHV1 pU42 (GenBank accession number AF322977; gi 109639413) (16) were generated by either a two-step nested PCR followed by a specific PCR (CCMV pC69 and ElHV1 pU42) or by direct amplification of the respective open reading frame (ORF) from genomic DNA (RhCMV pRh69, MCMV pM69, and HHV6A pU42). The respective amplicons were digested with adequate restriction enzymes followed by ligation into a pcDNA3.1-derived vector that facilitates expression in fusion with either a FLAG (pHM971) or a Myc (pHM1580) epitope (23).…”

Commentary: Trunkloads of Viruses

“…With very few exceptions, the amino acid sequence of a small conserved segment of the viral DNA polymerase (ϳ150 amino acids) is sufficient to not only reliably identify a virus as belonging to the evolutionary lineage represented by the Herpesviridae, but also their subfamily, and in most cases a recognized genus. Early analyses of such sequences from EEHV1 showed that sequences of its DNA polymerase and other highly conserved herpesvirus core genes branched near the base of the betaherpesvirus branch of the herpesvirus tree, leading to the suggestions that the virus might represent a new herpesvirus subfamily (13,14). EEHV1 is currently formally recognized as the species Elephantid herpesvirus 1, the type species in the Proboscivirus genus within the Betaherpesvirinae.…”