Activation of the HIV type 1 long terminal repeat by X-irradiation involves two main Re1/NF-kappa B DNA-binding complexes.
Transcription of human immunodeficiency virus type 1 (HIV-1) is regulated by multiple cis-acting regulatory elements located in the viral long terminal repeats (LTRs). HIV-1 LTR enhancer is activated by a variety of heterologous viral, chemical, and physical agents. Studies have demonstrated that irradiation by X-rays induces transcription under the control of the HIV-1 LTR and that ionizing radiations activate DNA binding of the nuclear transcription factor NF-kappa B. Using various constructs expressing a reporter gene under the control of complete or deleted LTRs of HIV-1, we evidenced that a sequence located in the U3 region was involved in X-ray activation of the HIV-1 LTR in the human colonic carcinoma cell line HT29. The cis-acting element conferring X-ray responsiveness is indistinguishable from HIV NF-kappa B tandem repeat binding sites (HIV-1, kappa B). The present work has examined the effects of X-irradiation on the NF-kappa B transcription factor. Furthermore, we characterized the subunit composition of the two major nuclear NF-kappa B complexes that bind HIV-1 kappa B after X-ray irradiation.
Institut de Chimie Biologique, Université de Provence, Marscelle, France.
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Imbert
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Champion
D000975:Antioxidants / Q000494:pharmacology; D002467:Cell Nucleus / Q000378:metabolism; D003110:Colonic Neoplasms; D004307:Dose-Response Relationship, Radiation; D005786:Gene Expression Regulation; D016325:HIV Long Terminal Repeat / Q000235:genetics / Q000528:radiation effects*; D015497:HIV-1 / Q000528:radiation effects*; D006801:Humans; D016328:NF-kappa B / Q000378:metabolism / Q000528:radiation effects*; D011392:Proline / Q000031:analogs & derivatives / Q000494:pharmacology; D013859:Thiocarbamates / Q000494:pharmacology; D014162:Transfection; D014407:Tumor Cells, Cultured
D000975:Antioxidants; D016328:NF-kappa B; D013859:Thiocarbamates; C066229:prolinedithiocarbamate; D011392:Proline