Trans-activation of the human immunodeficiency virus long terminal repeat sequences, expressed in an adenovirus vector, by the adenovirus E1A 13S protein.

The human immunodeficiency virus 1 (HIV-1) long terminal repeat (LTR) sequences were inserted into adenovirus in place of the E1 region. The HIV-1 LTR contained in this recombinant adenovirus responds to trans-activation by tatIII in a HeLa cell line constitutively expressing that HIV-1 gene product. In addition, the HIV-1 LTR is activated by the adenovirus E1A 13S, but not 12S or 9S, gene product when it is supplied in trans by a coinfecting wild-type adenovirus. The Rous sarcoma virus LTR, in a similar recombinant adenovirus, is insensitive to tatIII but is also trans-activated by the E1A 13S protein. The action of the 13S E1A and tatIII proteins are additive for the HIV-1 LTR in the context of adenovirus and they appear to act at the transcriptional level. As in HeLa cells, the adenovirus-borne HIV-1 LTR is inactive in the absence of a trans-activator in H9 and Jurkat cells, two human leukemic T-cell lines. This suggests that recombinant adenoviruses have diagnostic potential for the detection of trans-activators of the HIV-1 LTR that are present in circulating human lymphocytes.