The NF-kappa B binding sites in the human immunodeficiency virus type 1 long terminal repeat are not required for virus infectivity

Abstract

Mutations were introduced into the regulatory sequences in the long terminal repeat of an infectious molecular clone of the human immunodeficiency virus. Viruses in which the NF-KB binding sites were deleted or ones in which one or two Spl binding sites were mutated still replicated efficiently in human T lymphocytes. A deletion of the two NF-KcB sites plus the three Spl sites or a mutation of the tat-responsive region rendered the virus replication incompetent. Thus, the NF-KcB sequences are not required for human immunodeficiency virus infectivity; however, a tat-responsive region is essential.

Cell‐to‐Cell Contact Activates the Long Terminal Repeat of Human Immunodeficiency Virus 1 Through its κB Motif

“…or three deleted forms were used. LTR-ZucZ (Cavard et al, 1990), LTRANF-~B-lucZ (Leonard et al, 1989), LTRANRE-lucZ and LTR~NRE-ANF-KB-~u~Z (Zider et al, 1993) chimeric genes have been previously described (Fig. 1A).…”

“…The LTR-ANRE-lacZ insert was obtained after digestion by ScaI (-140 relative to the transcription start of HIV-1) and PstI of the LTR-lac2 and was subcloned in pGEM-1 (Promega; Zider et al, 1993). The ~LTR-ANF-KB-~u~Z plasmid was obtained after inserting the mutant LTR [containing a 29-bp deletion that removes the two NF-KB sites upstream of the lac2 gene and the simian-virus-40 polyadenylation signal from pCHl10 (Pharmacia) in pGEM-11 (Leonard et al, 1989). The ~LTR-ANRE-ANF-KB-~~cZ plasmid was constructed in pGEM-1 after cleavage by ScaI of the LTR-ANF-KB-~ucZ insert keeping intact the Spl sites (Zider et al, 1993).…”

Transcriptional regulation of HIV-1 LTR during antigen-dependent activation of primary T cells by dendritic cells

“…1). These proviral DNA containing mutations/ deletions in 3Ј-LTR were constructed by oligonucleotide-directed, site-specific mutagenesis, essentially as described by Leonard et al [6]. For measuring the promoter activity of LTR, a HindIII-XhoI fragment containing 3Ј-LTR (U3-R region) was inserted into the HindIII and XhoI site of the luciferase expression plasmid pHIV/L-Ad5Ј (provided by Dr. Y. Takebe, AIDS Research Center, National Institute of Infectious Diseases, Tokyo, Japan).…”

“…The number of copies per 10 4 CD4 ϩ T cells based on this In the regulatory region of the HIV-1 U3 LTR, two NF-B sites and three Sp1 sites are known (boxed). Based on the 3Ј-LTR sequence of NL432 [34], either deletion (dashed line) or mutation (underlined) was introduced as described [6,8]. Other representative motifs of transcription factor binding sites in the U3 region are also depicted.…”

“…HIV has two NF-B motifs and three Sp1 motifs in the promoter/enhancer region of the LTR. In earlier studies, it was shown that neither NF-B nor Sp1 is required for viral growth in established T cell lines or phytohemagglutinin (PHA)stimulated peripheral blood leukocytes (PBLs) [6][7][8]. In these studies, mostly cloned virus produced by transfection followed by expansion in cocultured T cell lines was used.…”