Genome of Bovine Herpesvirus 5

Abstract

Here we present the complete genomic sequence of bovine herpesvirus 5 (BHV-5), an alphaherpesvirus responsible for fatal meningoencephalitis in cattle. The 138,390-bp genome encodes 70 putative proteins and resembles the ␣2 subgroup of herpesviruses in genomic organization and gene content. BHV-5 is very similar to BHV-1, the etiological agent of infectious bovine rhinotracheitis, as reflected by the high level of amino acid identity in their protein repertoires (average, 82%). The highest similarity to BHV-1 products (>95% amino acid identity) is found in proteins involved in viral DNA replication and processing (UL5, UL15, UL29, and UL39) and in virion proteins (UL14, UL19, UL48, and US6). Among the least conserved (<75%) are the homologues of immediate-early (IE) proteins BICP0, BICP4, and BICP22, the three proteins being longer in BHV-5 than in BHV-1. The structure of the BHV-5 latency-related (LR) region departs markedly from that of BHV-1 in both coding and transcriptional regulatory regions. Given the potential significance of IE genes and the LR region in virus-neuron interactions, it is likely these differences contribute to BHV-5 neuropathogenicity.

Ruminant alphaherpesviruses related to bovine herpesvirus 1

“…The genomes of BoHV-1 and BoHV-5 have been sequenced [26,79,112]. The BoHV-5 genome is 138 390 bp long (72% G+C content), with 2 518 bp more than BoHV-1 (75% G+C content).…”

“…The BoHV-5 genome is 138 390 bp long (72% G+C content), with 2 518 bp more than BoHV-1 (75% G+C content). It includes 72 genes, of which 68 are present as single copies within the unique regions and two are completely located within the repeat region (BICP4 and BICP22) [26]. The BoHV-1 genome comprises 67 unique genes and two genes, both duplicated, in the inverted repeats [112].…”

“…The highest BoHV-5 similarity to BoHV-1 products (95% amino acid identity) is found in proteins involved in viral DNA replication and processing (UL5, UL15, UL29 and UL39) and in virion proteins (UL14, UL19, UL48 and US6). Among the least conserved (≤ 75%) are the homologues of immediate-early proteins BICP0, BICP4 and BICP22, these proteins being longer in BoHV-5 than in BoHV-1 [26]. It can be hypothesised that the same range of homology is shared by the other related ruminant alphaherpesviruses.…”

“…Based on the complete gB gene sequence, which is the most conserved between herpesviruses [48], the percentages of nucleotide sequence identity with BoHV-1 gB are 78.5% for CpHV-1, 84% for CvHV-2, 85.8% for CvHV-1, 87.4% for BoHV-5 and 87.7% for BuHV-1 [107]. The gC 2 and gD gene sequences are fully known for each ruminant alphaherpesviruses, except for BuHV-1 [26,29,64,112]. On this basis, the percentages of amino acid sequence identity between BoHV-1 and ElkHV-1 are 71.7% (gC) or 72.9% (gD) [29].…”

Bovine herpesvirus 1 infection and infectious bovine rhinotracheitis

“…In contrast, one gene is specific to BoHV-1 (UL0.5), whereas some others (e.g. circ gene) are peculiar to the Varicelloviruses [33]. The BoHV-1 genome encloses ten genes encoding glycoproteins (Fig.…”