title: Structure-guided peptidomimetic design leads to nanomolar beta-hairpin inhibitors of the Tat-TAR interaction of bovine immunodeficiency virus.
abstract: The Tat protein of immunodeficiency viruses is the main activator of viral gene expression. By binding specifically to its cognate site, the transactivator response element (TAR), Tat mediates a strong induction of the production of all viral transcripts. In seeking a new chemical solution to inhibiting viral protein-RNA interactions, we recently identified inhibitors of the viral Tat protein from the bovine immunodeficiency virus (BIV) using conformationally constrained beta-hairpin peptidomimetics. We identified a micromolar ligand, called BIV2, and the structure of its complex with BIV TAR was determined by NMR. In this work, we demonstrate that this chemistry can rapidly yield highly potent and selective ligands. On the basis of the structure, we synthesized and assayed libraries of mutant peptidomimetics. Remarkably, we were able in just a few rounds of design and synthesis to discover nanomolar inhibitors of the Tat-TAR interaction in BIV that selectively bind the BIV TAR RNA compared to RNA structures as closely related as the HIV-1 TAR or RRE elements. The molecular recognition principles developed in this study have been exploited in discovering related peptidomimetic inhibitors of the Tat-TAR interaction in HIV-1.
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Zafiria
authors.initials: Z
authors.lastname: Athanassiou
authors.forename: Krystyna
authors.initials: K
authors.lastname: Patora
authors.forename: Ricardo L A
authors.initials: RL
authors.lastname: Dias
authors.forename: Kerstin
authors.initials: K
authors.lastname: Moehle
authors.forename: John A
authors.initials: JA
authors.lastname: Robinson
authors.forename: Gabriele
authors.initials: G
authors.lastname: Varani
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D015696:Gene Products, tat / Q000037:antagonists & inhibitors* / Q000737:chemistry; D016087:Immunodeficiency Virus, Bovine / Q000235:genetics*; D018716:Molecular Mimicry; D019906:Nuclear Magnetic Resonance, Biomolecular; D010456:Peptides, Cyclic / Q000138:chemical synthesis / Q000494:pharmacology*; D017434:Protein Structure, Tertiary; D012367:RNA, Viral / Q000737:chemistry*; D016601:RNA-Binding Proteins / Q000037:antagonists & inhibitors*; D000099253:Trans-Activation Responsive RNA-Binding Protein
chemical_list: D015696:Gene Products, tat; D010456:Peptides, Cyclic; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D000099253:Trans-Activation Responsive RNA-Binding Protein; C517549:cyclo(Pro-Pro-Arg-Val-Arg-Thr-Arg-Gly-Lys-Arg-Arg-Ile-Arg-Val)