Regional specificity of HTLV-I proviral integration in the human genome.
The location of HTLV-I (human T-cell leukemia virus type 1) proviral sequences in the genome of infected human cells was explored by hybridization of a viral probe with compositional fractions of host-cell DNAs. In the twelve cases examined, HTLV-I sequences were absent from the GC-poorest 40% of the host genome (namely, from isochores that are below 39% GC). Transcriptionally inactive proviral sequences were localized in GC-poor isochores (comprised between 39% and 42-44% GC) of the human genome, which are characterized by a constant and low gene concentration. In contrast, transcriptionally active proviral sequences were found in the GC-rich and very GC-rich isochores, which are gene rich, transcriptionally and recombinationally active, and endowed with an open chromatin structure. Since GC-rich isochores are present in R'-bands and very GC-rich isochores form T-bands, these results also provide information on the location of HTLV-I proviral sequences in human chromosomes. The results obtained with HTLV-I are in agreement with the non-random, compartmentalized integration of animal retroviral sequences that had been previously observed in other viral-host systems. They provide, however, much more detailed information on the regional location of proviral sequences in the host genome and on the correlation between their transcription and their location.
Zoubak
S
S
Laboratoire de Génétique Moléculaire, Institut Jacques Monod, Paris, France.
Richardson
J H
JH
Rynditch
A
A
Höllsberg
P
P
Hafler
D A
DA
Boeri
E
E
Lever
A M
AM
Bernardi
G
G
D002461:Cell Line, Transformed; D002499:Centrifugation, Density Gradient; D002999:Clone Cells; D004247:DNA / Q000737:chemistry; D004279:DNA, Viral / Q000032:analysis; D015894:Genome, Human; D015490:HTLV-I Infections / Q000382:microbiology; D015368:Human T-lymphotropic virus 1 / Q000235:genetics*; D006801:Humans; D009693:Nucleic Acid Hybridization; D011533:Proviruses / Q000235:genetics*; D014158:Transcription, Genetic; D016662:Virus Integration / Q000235:genetics*
D004279:DNA, Viral; D004247:DNA