TY - JOUR T1 - NMR structure of a biologically active peptide containing the RNA-binding domain of human immunodeficiency virus type 1 Tat. A1 - Mujeeb, A LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English LA - English YR - 1994 UL - http://buscaintegrada.pucsp.br/vufind/Record/pubmed-44583 AB - The Tat protein of human immunodeficiency virus type 1 enhances transcription by binding to a specific RNA element on nascent viral transcripts. Binding is mediated by a 10-amino acid basic domain that is rich in arginines and lysines. Here we report the three-dimensional peptide backbone structure of a biologically active 25-mer peptide that contains the human immunodeficiency virus type 1 Tat basic domain linked to the core regulatory domain of another lentiviral Tat--i.e., that from equine infectious anemia virus. Circular dichroism and two-dimensional proton NMR studies of this hybrid peptide indicate that the Tat basic domain forms a stable alpha-helix, whereas the adjacent regulatory sequence is mostly in extended form. These findings suggest that the tendency to form stable alpha-helices may be a common property of arginine- and lysine-rich RNA-binding domains. KW - Research Article ER -