Chicken ovalbumin upstream promoter transcription factor binds to a negative regulatory region in the human immunodeficiency virus type 1 long terminal repeat.
The human immunodeficiency virus type 1 (HIV-1) long terminal repeat (LTR) contains a negative regulatory element (NRE) which downregulates the rate of LTR-directed transcription and HIV-1 replication. Within the NRE is a GGTCA palindrome, which binds a possible member of the steroid/thyroid hormone receptor superfamily. Mutation of this site leads to an increase in LTR-directed transcriptional activity compared with the wild type, consistent with the element's being a functional part of the NRE. The palindrome contains significant identity to the chicken ovalbumin upstream promoter (COUP) element to which COUP transcription factors (COUP-TFs), members of the steroid/thyroid hormone receptor superfamily, bind. We demonstrate here that human COUP-TFs can bind specifically to this HIV-1 COUP-like element in a manner identical to binding to ovalbumin COUP. We show that the predominant COUP-TF family member synthesized in T cells is the 68-kDa form, which is likely to be responsible for any in vivo function of the HIV-1 COUP-like element in these cells. Finally, we have identified three HIV-1 variant strains that contain mutations in the HIV-1 COUP-like element which affect the binding affinity of COUP-TF for these variant COUP elements.
Cooney
A J
AJ
Department of Cell Biology, Baylor College of Medicine, Houston, Texas 77030.
Tsai
S Y
SY
O'Malley
B W
BW
Tsai
M J
MJ
D001483:Base Sequence; D001665:Binding Sites; D051838:COUP Transcription Factor I; D004268:DNA-Binding Proteins; D014644:Genetic Variation; D015497:HIV-1 / Q000235:genetics*; D006367:HeLa Cells / Q000382:microbiology; D006801:Humans; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D011988:Receptors, Thyroid Hormone / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid; D014157:Transcription Factors / Q000235:genetics*
D051838:COUP Transcription Factor I; D004268:DNA-Binding Proteins; C497589:NR2F1 protein, human; D011988:Receptors, Thyroid Hormone; D014157:Transcription Factors