20980522

not annotated - annotated - LINNAEUS only

RNA aptamers directed to human immunodeficiency virus type 1 Gag polyprotein bind to the matrix and nucleocapsid domains and inhibit virus production.

Gag orchestrates the assembly and release of human immunodeficiency virus type 1 (HIV-1) particles. We explored here the potential of anti-Gag RNA aptamers to inhibit HIV-1 replication. In vitro, RNA aptamers raised against an HIV-1 Gag protein, lacking the N-terminal myristate and the C-terminal p6 (DP6-Gag), could bind to matrix protein (MA), nucleocapsid protein (NC), or entire DP6-Gag protein. Upon cotransfection with pNL4-3.Luc molecular clone into 293T cells, six of the aptamers caused mild inhibition (2- to 3-fold) in the extracellular capsid levels, and one aptamer displayed 20-fold inhibition. The reduction was not due to a release defect but reflected Gag mRNA levels. We hypothesized that the aptamers influence genomic RNA levels via perturbation of specific Gag-genomic RNA interactions. Binding studies revealed that the "NC-binders" specifically compete with the packaging signal (psi) of HIV-1 for binding to DP6-Gag. Therefore, we tested the ability of two NC-binders to inhibit viruses containing psi-region deletions (DeltaSL1 or DeltaSL3) and found that the NC-binders were no longer able to inhibit Gag synthesis. The inability of these aptamers to inhibit psi-deleted viruses correlated with the absence of competition with the corresponding psi transcripts lacking SL1 or SL3 for binding DP6-Gag in vitro. These results indicate that the NC-binding aptamers disrupt Gag-genomic RNA interaction and negatively affect genomic RNA transcription, processing, or stability. Our results reveal an essential interaction between HIV-1 Gag and the psi-region that may be distinct from that which occurs during the encapsidation of genomic RNA. Thus, anti-Gag aptamers can be an effective tool to perturb Gag-genomic RNA interactions.



Ann file

T1	Species 25 60	human immunodeficiency virus type 1

N1 Reference T1 Taxonomy:11676

T2 Species 198 233 human immunodeficiency virus type 1

N2 Reference T2 Taxonomy:11676

T3 Species 235 240 HIV-1

N3 Reference T3 Taxonomy:11676

T4 Species 320 325 HIV-1

N4 Reference T4 Taxonomy:11676

T5 Species 380 385 HIV-1

N5 Reference T5 Taxonomy:11676

T6 Species 1075 1080 HIV-1

N6 Reference T6 Taxonomy:11676

T7 Species 1715 1720 HIV-1

N7 Reference T7 Taxonomy:11676