title: Selection of TAR RNA-binding chameleon peptides by using a retroviral replication system.
abstract: The interaction between the arginine-rich motif (ARM) of the human immunodeficiency virus (HIV) Tat protein and TAR RNA is essential for Tat activation and viral replication. Two related lentiviruses, bovine immunodeficiency virus (BIV) and Jembrana disease virus (JDV), also require Tat ARM-TAR interactions to mediate activation, but the viruses have evolved different RNA-binding strategies. Interestingly, the JDV ARM can act as a "chameleon," adopting both the HIV and BIV TAR binding modes. To examine how RNA-protein interactions may evolve in a viral context and possibly to identify peptides that recognize HIV TAR in novel ways, we devised a retroviral system based on HIV replication to amplify and select for RNA binders. We constructed a combinatorial peptide library based on the BIV Tat ARM and identified peptides that, like the JDV Tat ARM, also function through HIV TAR, revealing unexpected sequence characteristics of an RNA-binding chameleon. The results suggest that a retroviral screening approach may help identify high-affinity TAR binders and may provide new insights into the evolution of RNA-protein interactions.
authors.affiliation: Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California 94143-2280, USA.
authors.forename: Baode
authors.initials: B
authors.lastname: Xie
authors.forename: Valerie
authors.initials: V
authors.lastname: Calabro
authors.forename: Mark A
authors.initials: MA
authors.lastname: Wainberg
authors.forename: Alan D
authors.initials: AD
authors.lastname: Frankel
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001120:Arginine / Q000737:chemistry; D002417:Cattle; D002460:Cell Line; D020650:Combinatorial Chemistry Techniques; D015696:Gene Products, tat / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016325:HIV Long Terminal Repeat / Q000235:genetics / Q000502:physiology*; D015497:HIV-1 / Q000235:genetics / Q000502:physiology; D006801:Humans; D016086:Lentivirus / Q000235:genetics / Q000502:physiology*; D051379:Mice; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D019151:Peptide Library; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000378:metabolism; D013329:Structure-Activity Relationship; D014779:Virus Replication; D054322:tat Gene Products, Human Immunodeficiency Virus; D000099253:Trans-Activation Responsive RNA-Binding Protein
chemical_list: D001120:Arginine; D015696:Gene Products, tat; D019151:Peptide Library; D010455:Peptides; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D054322:tat Gene Products, Human Immunodeficiency Virus; D000099253:Trans-Activation Responsive RNA-Binding Protein