Structural and functional analysis of the visna virus Rev-response element.
The distantly related lentiviruses human immunodeficiency virus type 1 (HIV-1) and visna virus each encode a posttranscriptional regulatory protein, termed Rev, that is critical for expression of the viral structural proteins. We genetically mapped the cis-acting target sequence for visna virus Rev, the visna virus Rev-response element or RRE-V, to a complex 176-nucleotide RNA stem-loop structure that coincides with sequences encoding the N terminus of the transmembrane component of envelope. The computer-predicted structure of the RRE-V was validated by in vitro analysis of structure-specific RNase cleavage patterns. The visna virus Rev protein was shown to interact specifically with the genetically defined RRE-V in vitro but was unable to bind the HIV-1 RRE. Similarly, HIV-1 Rev was also unable to bind the RRE-V specifically. We therefore conclude that the HIV-1 and visna virus Rev proteins, while functionally analogous, nevertheless display distinct RNA sequence specificities. These findings provide a biochemical explanation for the observation that these two viral regulatory proteins are functional only in the homologous viral system.
Tiley
L S
LS
Howard Hughes Medical Institute, Duke University Medical Center, Durham, North Carolina 27710.
Cullen
B R
BR
D001483:Base Sequence; D002874:Chromosome Mapping; D015694:Gene Products, rev / Q000378:metabolism*; D015757:Genes, rev / Q000235:genetics*; D015497:HIV-1 / Q000235:genetics; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D012260:Ribonucleases / Q000378:metabolism; D013379:Substrate Specificity; D014158:Transcription, Genetic; D014790:Visna-maedi virus / Q000235:genetics*; D054321:rev Gene Products, Human Immunodeficiency Virus
D015694:Gene Products, rev; D011993:Recombinant Fusion Proteins; D054321:rev Gene Products, Human Immunodeficiency Virus; D012260:Ribonucleases