Use of U3 promotor from the LTR region of bovine leukemia virus for expressing genes for antiviral antisense RNAs in cell cultures

: The possibility was studied to use the U3 promoter from LTR region of bovine leukemia virus to control the expression of the antisense RNA genes directed against the BLV genome in cell cultures FLK-BLV, CC81, and HeLa. The genetic engineering constructions were obtained carrying the reporter beta-galactosidase gene and the genome of antisense RNA to R-U5 region of the viral genome under the control of the promoter. The functioning of the viral promoter was studied in three cell lines. Its specific activation and kinetics of inhibition of BLV virus reproduction in cell culture CC81 have been demonstrated. The maximal 75% level of the viral reproduction inhibition was achieved at threefold molar excess of the plasmid containing the antisense RNA gene over the pregenomic viral DNA.