Two dimerization domains in the trans-activation response RNA-binding protein (TRBP) individually reverse the protein kinase R inhibition of HIV-1 long terminal repeat expression
Autor: | Damian F. J. Purcell, Richard Benarous, Aïcha Daher, Anne Gatignol, Pier-Luigi Battisti, Florence Bois, Michèle Longuet, Dominique Dorin, Catherine Vaquero, Emmanuel Ségéral, Eliane F. Meurs, Sylvie Bannwarth |
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Rok vydání: | 2001 |
Předmět: |
viruses
RNA-binding protein Biology Transfection environment and public health Biochemistry eIF-2 Kinase Genes Reporter Two-Hybrid System Techniques Gene expression Humans Amino Acids Phosphorylation Luciferases Molecular Biology HIV Long Terminal Repeat chemistry.chemical_classification Binding Sites Models Genetic Wild type virus diseases RNA RNA-Binding Proteins Cell Biology biochemical phenomena metabolism and nutrition Protein kinase R Molecular biology Long terminal repeat Yeast Amino acid Protein Structure Tertiary enzymes and coenzymes (carbohydrates) chemistry Mutation Dimerization Gene Deletion HeLa Cells Plasmids Protein Binding |
Zdroj: | The Journal of biological chemistry. 276(36) |
ISSN: | 0021-9258 |
Popis: | Trans-activation response (TAR) RNA-binding protein (TRBP) is a cellular protein that binds to the human immunodeficiency virus-1 (HIV-1) TAR element RNA. It has two double-stranded RNA binding domains (dsRBDs), but only one is functional for TAR binding. TRBP interacts with the interferon-induced protein kinase R (PKR) and inhibits its activity. We used the yeast two-hybrid assay to map the interaction sites between the two proteins. We show that TRBP and PKR-N (178 first amino acids of PKR) interact with PKR wild type and inhibit the PKR-induced yeast growth defect in this assay. We characterized two independent PKR-binding sites in TRBP. These sites are located in each dsRBD in TRBP, indicating that PKR-TRBP interaction does not require the RNA binding activity present only in dsRBD2. TRBP and its fragments that interact with PKR reverse the PKR-induced suppression of HIV-1 long terminal repeat expression. In addition, TRBP activates the HIV-1 long terminal repeat expression to a larger extent than the addition of each domain. These data suggest that TRBP activates gene expression in PKR-dependent and PKR-independent manners. |
Databáze: | OpenAIRE |
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