title: Activity of core-modified 10-23 DNAzymes against HCV.
abstract: The highly conserved untranslated regions of the hepatitis C virus (HCV) play a fundamental role in viral translation and replication and are therefore attractive targets for drug development. A set of modified DNAzymes carrying (2'R)-, (2'S)-2'-deoxy-2'-C-methyl- and -2'-O-methylnucleosides at various positions of the catalytic core were assayed against the 5'-internal ribosome entry site element (5'-IRES) region of HCV. Intracellular stability studies showed that the highest stabilization effects were obtained when the DNAzymes' cores were jointly modified with 2'-C-methyl- and 2'-O-methylnucleosides, yielding an increase by up to fivefold in the total DNAzyme accumulation within the cell milieu within 48 h of transfection. Different regions of the HCV IRES were explored with unmodified 10-23 DNAzymes for accessibility. A subset of these positions was tested for DNAzyme activity using an HCV IRES-firefly luciferase translation-dependent RNA (IRES-FLuc) transcript, in the rabbit reticulocyte lysate system and in the Huh-7 human hepatocarcinoma cell line. Inhibition of IRES-dependent translation by up to 65 % was observed for DNAzymes targeting its 285 position, and it was also shown that the modified DNAzymes are as active as the unmodified one.
authors: INGEBI (CONICET), Vuelta de Obligado 2490-(1428), Buenos Aires (Argentina).
authors: Laura
authors: L
authors: Robaldo
authors: Alfredo
authors: A
authors: Berzal-Herranz
authors: Javier M
authors: JM
authors: Montserrat
authors: Adolfo M
authors: AM
authors: Iribarren
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000138:chemical synthesis* / Q000494:pharmacology*; D001483:Base Sequence; D045744:Cell Line, Tumor; D021881:DNA, Catalytic / Q000138:chemical synthesis* / Q000494:pharmacology*; D004277:DNA, Single-Stranded / Q000138:chemical synthesis* / Q000494:pharmacology*; D015967:Gene Expression Regulation, Viral / Q000187:drug effects; D016174:Hepacivirus / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D011817:Rabbits; D012156:Reticulocytes / Q000187:drug effects / Q000378:metabolism; D012270:Ribosomes / Q000187:drug effects; D020506:Untranslated Regions
chemical_list: D000998:Antiviral Agents; D021881:DNA, Catalytic; D004277:DNA, Single-Stranded; C402582:RNA-cleaving DNA 10-23; D020506:Untranslated Regions
keywords: 2′-methylnucleosides; DNAzymes; antiviral agents; hepatitis C virus; oligonucleotides