Selection by phage display of peptides targeting the HIV-1 TAR element.
As transcription regulatory element, the HIV-1 TAR RNA element is a promising target to inhibit viral replication; indeed, ligands of TAR RNA could prevent the transcription trans-activation process. Phage display in vitro selection was undertaken to select peptidic ligands of TAR RNA. In preliminary experiments, the selection was performed in a magnesium rich buffer (3 mM), but only phages targeted to plastic wells or streptavidin emerged; in addition, a "super-infectious" phage present in the New England Biolabs library (SVSVGMKPSPRP) selected by others with different targets was cloned, due to a high amplification potential. In contrast, the absence of magnesium or an increasing magnesium concentration (0 to 0.5 mM) led to phage selection with 57 amino acid peptides. K(D)s of 420-550 nM were measured by filter binding assays; a significant specificity was obtained when TAR target was compared with unrelated RNA targets. Surprisingly, the binding of selected peptides does not depend on the magnesium concentration.
Kolb
Gaëlle
G
INSERM U386, Université Victor Segalen Bordeaux 2, Bordeaux cedex, France.
Boiziau
Claudine
C
D002021:Buffers; D016325:HIV Long Terminal Repeat; D015497:HIV-1 / Q000235:genetics* / Q000502:physiology; D008274:Magnesium; D009690:Nucleic Acid Conformation; D019151:Peptide Library; D016601:RNA-Binding Proteins / Q000378:metabolism; D014779:Virus Replication
D002021:Buffers; D019151:Peptide Library; D016601:RNA-Binding Proteins; D008274:Magnesium