Genomic diversity among bovine herpesvirus 4 field isolates

Abstract

Twenty-eight Belgian field isolates of bovine herpesvirus 4 (BHV-4) coming from a variety of clinical diseases have been studied by restriction analysis and Southern blot hybridization. The unique central part of the genome was very well conserved among strains; only one variation in a restriction site was detected in 3 isolates which contain an additional EcoRI site also present in the LVR 140 strain; three regions in the unique part of the genome varied in size, one of these was highly variable. The polyrepetitive fragments (prDNAs) situated in tandem at both genomic ends were also variable in size; most of the isolates exhibited prDNA units of one size (major prDNA) and some of them also contained prDNA units having a different size and present in a lower amount (minor prDNA) than the major prDNA. Other isolates possessed two major prDNAs of different sizes which were both present in the same genome. The left junction fragment between the unique and the repeated sequences was also highly variable. No relationship could be established between the restriction pattern and the origin of the isolates; patterns of isolates coming from the same herd were similar except in one case. This study provides a view of the genome variability existing between BHV-4 field isolates.

Analysis of bovine herpesvirus 4 genomic regions located outside the conserved gammaherpesvirus gene blocks

“…Direct nucleotide sequence repeats were found in the B and E regions. These regions, without ORFs, have been shown to vary in size between BHV-4 isolates (Bublot et al, , 1991. A variable number of repeats is probably responsible for this size variation as is the case with many other herpesviruses Kinoshita et al, 1988;Simon et al, 1989).…”

“…The BHV-4 virion contains a dsDNA of 144_+6 kb (Ehlers et al, 1985). Molecular data have shown a clear relationship between BHV-4 and the members of the subfamily gammaherpesvirinae (Honess, 1984;Bublot et al, 1990Bublot et al, , 1991Bublot et al, , 1992van Santen, 1991 ;Thiry et al, 1992). Therefore, the Herpesvirus Study Group of the International Committee on Taxonomy of Viruses recently assigned BHV-4 to this subfamily (Roizman et al, 1992).…”

Antigenic and genomic identity between simian herpesvirus aotus type 2 and bovine herpesvirus type 4

“…The two additional BamHI sites present at the left end of HVA-2 L-DNA and the size variation of the corresponding BHV-4 (V. Test) BamHI fragment K have not previously been reported; all the other size variations detected in this study (HindlII fragment Q, BamHI fragment I, Jl and the prDNA fragment) have been observed in DNA from different BHV-4 strains (Ehlers et al, 1985;Bublot et al, 1990Bublot et al, , 1991. Furthermore, the presence of a variable amount of prDNA of one size in different DNA preparations, also observed for HVA-2 by Fuchs et al (1985), has been described for BHV-4 .…”

“…The size variation present at the left end of L-DNA could be localized to HindIII fragment Q (positions 0.063 to 0.082) (Fig. 1 a and 3); HindIII fragment U, which is known to vary in size between BHV-4 strains (Bublot et aL, , 1991, was the same size in the two strains analysed in this study (Fig. 1 a).…”

Characterization of two BHV-4 strains isolated in the Czech Republic

“…The unique central part of the genome is very well conserved among strains with a few variations due to the presence or absence of a restriction site and fragment length variation. A study of genomic diversity of field isolates in Belgium revealed some Movar-like isolates carrying an additional EcoRI site (Bublot et al, 1991b). The length variations occurred in the junction regions between repeated and unique sequences and two regions V1, V2 where the left junction and V1 regions are highly polymorphic (Bublot et al, , 1991a.…”