TY - JOUR
T1 - Distinct DNA targets for trans-activation by HTLV-1 tax and adenovirus E1A
AU - Nicholas, John
AU - Nevins, Joseph R.
PY - 1991/5
Y1 - 1991/5
N2 - The HTLV-1 LTR is trans-activated by both the HTLV-1 tax(p40x) and adenovirus ElA gene products. Previous experiments have localized tax-responsive cis-elements to three 21-bp repeat units within the promoter, as well as a fourth region located between the middle and proximal repeats. A sequence TGACG, resembling the ATF/CREB recognition element, is located at the center of each of these repeat units. Mutation of this ATF/CREB site in the 21-bp repeats impairs both tax and E1A-dependent trans-activation. However, assays of a variety of promoter mutants demonstrate that sequences required for E1A and tax induction differ, suggesting that these two viral trans-activators target different factors. In addition, although the adenovirus E4 promoter also contains three ATF/CREB sites involved in E1A activation, tax does not activate this promoter. Finally, we also find that the TATAA element of the HTLV-1 LTR contributes to E1A-dependent activation but not tax activation. We conclude that although both trans-activators exhibit similarities in their activation properties, the targets for activation must differ.
AB - The HTLV-1 LTR is trans-activated by both the HTLV-1 tax(p40x) and adenovirus ElA gene products. Previous experiments have localized tax-responsive cis-elements to three 21-bp repeat units within the promoter, as well as a fourth region located between the middle and proximal repeats. A sequence TGACG, resembling the ATF/CREB recognition element, is located at the center of each of these repeat units. Mutation of this ATF/CREB site in the 21-bp repeats impairs both tax and E1A-dependent trans-activation. However, assays of a variety of promoter mutants demonstrate that sequences required for E1A and tax induction differ, suggesting that these two viral trans-activators target different factors. In addition, although the adenovirus E4 promoter also contains three ATF/CREB sites involved in E1A activation, tax does not activate this promoter. Finally, we also find that the TATAA element of the HTLV-1 LTR contributes to E1A-dependent activation but not tax activation. We conclude that although both trans-activators exhibit similarities in their activation properties, the targets for activation must differ.
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U2 - 10.1016/0042-6822(91)90659-Y
DO - 10.1016/0042-6822(91)90659-Y
M3 - Article
C2 - 1827222
AN - SCOPUS:0025847329
SN - 0042-6822
VL - 182
SP - 156
EP - 167
JO - Virology
JF - Virology
IS - 1
ER -