Assessment of the base sequence homology between the two subtypes of equine herpesvirus 1

Abstract

The magnitude of the genetic relatedness of the two antigenic subtypes of equine herpesvirus 1 (EHV-1) was determined by DNA-DNA reassociation kinetics. Denatured, labeled viral DNA from one EHV-1 subtype was allowed to reassociate in the presence or absence of the unlabeled heterologous viral DNA. The initial rate of reassociation of either labeled viral DNA was increased by the presence of the heterologous viral DNA to an extent indicating 10 to 20% homology between the two EHV-1 genomes. Similar estimates of the amount of homology between the genomes of the two EHV-1 subtypes were obtained by determining the maximum fraction of labeled viral DNA that could be made resistant to S1 nuclease by hybridization with a large molar excess of the unlabeled, heterologous viral DNA. Analysis of the thermal stability of the subtype 1-subtype 2 heteroduplex DNA indicated approximately 30%o base pair mismatching within the hybrid DNA molecules. Cross-hybridization of 2p_

The increased prevalence of neuropathogenic strains of EHV-1 in equine abortions

“…We hypothesize that the neuropathogenic strain of EHV-1 was associated with sporadic cases of equine herpesvirus abortion prior to the 1960's, and the proportion of EHV-1 abortion isolates which posses the neuropathogenic genotype has increased in recent years in comparison to previous decades in Central Kentucky. To test this hypothesis, a real-time Taq Carlsbad, CA), supplemented with 10% fetal bovine serum (10% FBS) and gentamicin reagent solution (50-µg/ml; Invitrogen) as previously described (Allen et al, 1977;Allen and Turtinen, 1982;Turtinen et al, 1981). In the present study, the KyED cells were used between passages 7 and 10.…”

Genomic termini of equine herpesvirus 1

“…Equine herpesvirus 1 (EHV-1) is a significant viral pathogen of horses. Virus strains grouped as EHV-1 by biological markers and molecular biological means are associated with abortion, respiratory tract infection, and neurological disease of horses (1,2,6,21,22,28). On the basis of molecular biological and serological properties, EHV-1 has also been found to be associated with disease conditions in bovine animals (8).…”

Animal cytomegaloviruses.

“…The detection of intranuclear inclusions in the salivary glands of guinea pigs (114,160) and the subsequent demonstration that the inclusions were the result of a viral infection (70) heralded the usefulness of the guinea pig as a model for studying CMV infections. The incidence of infection in guinea pigs ranges from 25 to 84% (8, 70, 147, 160) and appears to be dependent on breeding conditions (27,147) and sexual contact (6 During natural fGPCMV infection clinical symptoms and gross lesions are .psually not detected, and evidence for infection must be 6btained by microscopic examination, virus isolation, or detection of GPCMV-neutralizing antibody (72). Experimental intravenous, subcutaneous, intratracheal, or intraperitoneal inoculation with virus serially passaged from animal to animal as tissue homogenates or serially passaged in tissue culture resulted in the localization of the virus infection in the submaxillary glands of young guinea pigs (8,71,129,155,189,190,306).…”