RESUMO
In contrast to previous findings, the Ab4 isolate of equid herpesvirus-1 (EHV-1) was shown to share homology with the G9 isolate of equid herpesvirus-2 (EHV-2). Using Southern blotting and stringent hybridization conditions, a significant proportion of this cross-hybridization was identified by the immediate-early gene-3 (IE-3) probe from herpes simplex virus-1 (HSV-1). The HSV-1 UL48 gene probe (encoding the IE gene transactivating protein VmW65, which is also known as alpha-TIF or VP16) was used to identify and isolate its counterpart in EHV-1. The relevance of shared homology to transactivation is being investigated.
Assuntos
Citomegalovirus/genética , Herpesvirus Equídeo 1/genética , Simplexvirus/genética , Southern Blotting , Células Cultivadas , Clonagem Molecular , Sondas de DNA , DNA Viral/análise , DNA Viral/isolamento & purificação , Polimorfismo de Fragmento de Restrição , Mapeamento por RestriçãoRESUMO
Consensus cis-acting DNA sequences upstream of the immediate early (IE) gene of equid herpesvirus type 1 (EHV-1, strain Ab4) were identified. One copy of the conserved motif TAATGARATTC, which is the binding site for the host cellular factor Oct-1 and herpes simplex virus type 1 (HSV-1) virion protein, VmW65, complex, was identified at positions -630 to -620. Using transient transfections and chloramphenicol acetyltransferase assays the IE promoter of EHV-1 was shown to be trans-activated by VmW65 within the region -685 to +73. Ultraviolet light-inactivated EHV-1 was able to stimulate the expression of the IE gene of EHV-1 as well as HSV-1, indicating that EHV-1 possesses a protein equivalent to VmW65. The ubiquitous equid herpesvirus type 2 (EHV-2), which is not known to be a primary pathogen, was also able to trans-activate the EHV-1 and HSV-1 IE genes. Further work is being performed in order to identify the nature of the EHV-1 and EHV-2 trans-activating proteins.
