Cytomegalovirus activates transcription directed by the long terminal repeat of human immunodeficiency virus type 1.
Proteins encoded by a variety of DNA viruses activate gene expression from the promoter within the long terminal repeat (LTR) of the human immunodeficiency virus type 1 (HIV-1). The mechanism by which immediate-early (IE) gene products of human cytomegalovirus (CMV) activate expression from the HIV-1 LTR was examined in transient expression assays in cultures of human cells by using plasmids containing the LTR linked to the bacterial chloramphenicol acetyltransferase (CAT) gene and a plasmid expressing the CMV IE gene. Analysis of clustered site mutations within the HIV-1 LTR revealed that sequences from nucleotides -6 to +20 (relative to the start site of transcription) are critical for responsiveness to transactivation by CMV IE gene products. This region partially overlaps the trans-acting response element (+19 to +42) required for function of the HIV-1 transactivator. The CMV IE gene was shown to increase the steady-state levels of both prematurely terminated and full-length transcripts initiated within the LTR. These results support a model in which CMV IE gene products act through a specific regulatory element in the HIV-1 LTR to increase viral transcription.
Barry
P A
PA
Department of Medical Pathology, University of California, Davis 95616.
Pratt-Lowe
E
E
Peterlin
B M
BM
Luciw
P A
PA
D001483:Base Sequence; D002460:Cell Line; D003587:Cytomegalovirus / Q000235:genetics*; D005809:Genes, Regulator; D005814:Genes, Viral; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D009154:Mutation; D009690:Nucleic Acid Conformation; D011401:Promoter Regions, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D015533:Transcriptional Activation; D014162:Transfection