The Epstein-Barr virus BRLF1 immediate-early gene product transactivates the human immunodeficiency virus type 1 long terminal repeat by a mechanism which is enhancer independent.

The Epstein-Barr virus (EBV) immediate-early gene product, BRLF1, transactivates the human immunodeficiency virus type 1 (HIV-1) long terminal repeat. BRLF1-induced transactivation of HIV-1 promoter constructs is accompanied by an increase in plasmid mRNA and is reporter gene independent. Previously, BRLF1 transactivation of EBV promoters has been mapped to regions which function as enhancer elements. Deletional analysis demonstrates that BRLF1 transactivation of the HIV-1 promoter does not require the HIV-1 enhancer. Thus, the EBV BRLF1 gene product may transactivate by at least two different mechanisms, one mechanism involving certain enhancer elements and another mechanism which is enhancer independent