CYTOCHEMICAL ANALYSIS OF HUMAN T-CELL LEUKEMIA-VIRUS I LTR-REGULATED BETA-GALACTOSIDASE GENE-EXPRESSION USING A NOVEL INTEGRATED CELL SYSTEM

To develop a reporter system to study the response of,an integrated re troviral LTR and cellular and viral events which influence transcripti on, the 5' LTR of HTLV-1 was coupled to the Escherichia coli beta-gala ctosidase gene (lacZ). This construct was assembled within a vector co ntaining the neomycin resistance gene controlled by the SV40 promoter, and introduced into HeLa cells. Expression from the LTR in one clone was upregulated by positive regulators of HTLV-1 expression, including 12-O-tetradecanoylphorbol-13-acetate (TPA) and the HTLV-1 transregula tory protein (tax), as has been previously reported using transient tr ansfection assays. This method proved to be a rapid and reproducible a ssay for the measurement of integrated viral LTR activation in a singl e cell system.