Transcriptional suppression of in vitro-integrated human immunodeficiency virus type 1 does not correlate with proviral DNA methylation.
Persistence of human immunodeficiency virus type 1 (HIV-1) constitutes a major obstacle in the control of HIV-1 infection. Here we investigated whether the CpG methylation of the HIV-1 promoter can directly influence the expression of the HIV-1 genome and thereby contribute to the persistence and latency of HIV-1. The levels of CpG methylation in the promoter of HIV-1 were studied after bisulfite-induced modification of DNA in five Jurkat clonal cell lines transduced by an HIV-1 long terminal repeat (LTR)-driven retroviral vector and expressing enhanced green fluorescent protein (GFP) and in primary resting memory T cells challenged with HIV-1 or with an HIV-1-derived retroviral vector. Basal HIV-1 promoter activities were low or undetectable in three tested HIV-1 LTR-GFP clones, one of which encoded the Tat protein, and they reached medium or high levels in two other clones. The CpG dinucleotide that occurred in a latently infected clonal cell line 240 nucleotides upstream of the transcription start remained methylated after reactivation of HIV-1 transcription with 10 nM phorbol-12-myristate-13-acetate. In two clones showing a medium promoter activity and in resting memory T cells, the HIV-1 LTR was generally not methylated. Our results show that the methylation profiles of the HIV-1 LTR, including those present in latently infected cells, are low and do not correlate with the transcriptional activity. We suggest that, in a noncloned cellular population in which the HIV-1 proviruses are randomly integrated in the human genome, HIV-1 latency is imperfectly controlled by CpG methylation and is inherently accompanied by residual replication.
Pion
Marjorie
M
INSERM U372, Unité de Pathogénie des Infections à Lentivirus, Parc Scientifique et Technologique de Luminy, 13276 Marseille, France.
Jordan
Albert
A
Biancotto
Angelique
A
Dequiedt
Franck
F
Gondois-Rey
Françoise
F
Rondeau
Sophie
S
Vigne
Robert
R
Hejnar
Jiri
J
Verdin
Eric
E
Hirsch
Ivan
I
D001483:Base Sequence; D018899:CpG Islands; D019175:DNA Methylation; D004279:DNA, Viral / Q000235:genetics* / Q000378:metabolism*; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins; D016325:HIV Long Terminal Repeat; D015497:HIV-1 / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D007156:Immunologic Memory; D066298:In Vitro Techniques; D019169:Jurkat Cells; D008164:Luminescent Proteins / Q000235:genetics; D011401:Promoter Regions, Genetic; D011533:Proviruses / Q000235:genetics / Q000378:metabolism; D013489:Suppression, Genetic; D013601:T-Lymphocytes / Q000276:immunology; D014161:Transduction, Genetic; D014775:Virus Activation / Q000235:genetics; D016662:Virus Integration / Q000235:genetics
D004279:DNA, Viral; D008164:Luminescent Proteins; D049452:Green Fluorescent Proteins