trans-activation of the HIV-1 LTR by the HIV-1 Tat and HTLV-I Tax proteins is mediated by different cis-acting sequences.
Human immunodeficiency virus type 1 (HIV-1) gene expression is regulated by viral and cellular factors interacting with cis-elements located in the retroviral long terminal repeat (LTR). In this report we analyzed HIV-1 LTR-specific regulatory sequences responsive to the HIV-1 Tat and HTLV-I Tax trans-activator proteins. Our results indicate that the Sp1 binding sites in the HIV-1 LTR are crucially involved in Tat-mediated gene expression in human Jurkat T-cells whereas they are dispensable for HTLV-I Tax-induced activation. In contrast, the NF-kB binding sites within the HIV-1 LTR are essential for Tax-mediated transcription but had only marginal effect on Tat-induced reporter gene expression.
Zimmermann
K
K
SANDOZ Research Institute Vienna, Austria.
Dobrovnik
M
M
Ballaun
C
C
Bevec
D
D
Hauber
J
J
Böhnlein
E
E
D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002522:Chlorocebus aethiops; D004252:DNA Mutational Analysis; D004279:DNA, Viral / Q000235:genetics; D015967:Gene Expression Regulation, Viral; D015696:Gene Products, tat / Q000502:physiology*; D016356:Gene Products, tax / Q000502:physiology*; D016325:HIV Long Terminal Repeat / Q000235:genetics*; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D066298:In Vitro Techniques; D008969:Molecular Sequence Data; D012045:Regulatory Sequences, Nucleic Acid; D054322:tat Gene Products, Human Immunodeficiency Virus
D004279:DNA, Viral; D015696:Gene Products, tat; D016356:Gene Products, tax; D054322:tat Gene Products, Human Immunodeficiency Virus