23
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Molecular Mechanisms of Antisense Oligonucleotides

      research-article
      Nucleic Acid Therapeutics
      Mary Ann Liebert, Inc.
      RNase H, oligonucleotide, antisense, mechanisms, RNA, DNA

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          In 1987, when I became interested in the notion of antisense technology, I returned to my roots in RNA biochemistry and began work to understand how oligonucleotides behave in biological systems. Since 1989, my research has focused primarily on this topic, although I have been involved in most areas of research in antisense technology. I believe that the art of excellent science is to frame large important questions that are perhaps not immediately answerable with existing knowledge and methods, and then conceive a long-term (multiyear) research strategy that begins by answering the most pressing answerable questions on the path to the long-term goals. Then, a step-by-step research pathway that will address the strategic questions posed must be implemented, adjusting the plan as new things are learned. This is the approach we have taken at Ionis. Obviously, to create antisense technology, we have had to address a wide array of strategic questions, for example, the medicinal chemistry of oligonucleotides, manufacturing and analytical methods, pharmacokinetics and toxicology, as well as questions about the molecular pharmacology of antisense oligonucleotides (ASOs). Each of these endeavors has consumed nearly three decades of scientific effort, is still very much a work-in-progress, and has resulted in hundreds of publications. As a recipient of the Lifetime Achievement Award 2016 granted by the Oligonucleotide Therapeutic Society, in this note, my goal is to summarize the contributions of my group to the efforts to understand the molecular mechanisms of ASOs.

          Related collections

          Most cited references62

          • Record: found
          • Abstract: found
          • Article: not found

          Efficient reduction of target RNAs by small interfering RNA and RNase H-dependent antisense agents. A comparative analysis.

          RNA interference can be considered as an antisense mechanism of action that utilizes a double-stranded RNase to promote hydrolysis of the target RNA. We have performed a comparative study of optimized antisense oligonucleotides designed to work by an RNA interference mechanism to oligonucleotides designed to work by an RNase H-dependent mechanism in human cells. The potency, maximal effectiveness, duration of action, and sequence specificity of optimized RNase H-dependent oligonucleotides and small interfering RNA (siRNA) oligonucleotide duplexes were evaluated and found to be comparable. Effects of base mismatches on activity were determined to be position-dependent for both siRNA oligonucleotides and RNase H-dependent oligonucleotides. In addition, we determined that the activity of both siRNA oligonucleotides and RNase H-dependent oligonucleotides is affected by the secondary structure of the target mRNA. To determine whether positions on target RNA identified as being susceptible for RNase H-mediated degradation would be coincident with siRNA target sites, we evaluated the effectiveness of siRNAs designed to bind the same position on the target mRNA as RNase H-dependent oligonucleotides. Examination of 80 siRNA oligonucleotide duplexes designed to bind to RNA from four distinct human genes revealed that, in general, activity correlated with the activity to RNase H-dependent oligonucleotides designed to the same site, although some exceptions were noted. The one major difference between the two strategies is that RNase H-dependent oligonucleotides were determined to be active when directed against targets in the pre-mRNA, whereas siRNAs were not. These results demonstrate that siRNA oligonucleotide- and RNase H-dependent antisense strategies are both valid strategies for evaluating function of genes in cell-based assays.
            Bookmark
            • Record: found
            • Abstract: not found
            • Article: not found

            Inhibition of Rous sarcoma virus replication and cell transformation by a specific oligodeoxynucleotide.

              Bookmark
              • Record: found
              • Abstract: found
              • Article: found
              Is Open Access

              Identification and characterization of intracellular proteins that bind oligonucleotides with phosphorothioate linkages

              Although the RNase H-dependent mechanism of inhibition of gene expression by chemically modified antisense oligonucleotides (ASOs) has been well characterized, little is known about the interactions between ASOs and intracellular proteins that may alter cellular localization and/or potency of ASOs. Here, we report the identification of 56 intracellular ASO-binding proteins using multi-step affinity selection approaches. Many of the tested proteins had no significant effect on ASO activity; however, some proteins, including La/SSB, NPM1, ANXA2, VARS and PC4, appeared to enhance ASO activities, likely through mechanisms related to subcellular distribution. VARS and ANXA2 co-localized with ASOs in endocytic organelles, and reduction in the level of VARS altered lysosome/ASO localization patterns, implying that these proteins may facilitate ASO release from the endocytic pathway. Depletion of La and NPM1 reduced nuclear ASO levels, suggesting potential roles in ASO nuclear accumulation. On the other hand, Ku70 and Ku80 proteins inhibited ASO activity, most likely by competition with RNase H1 for ASO/RNA duplex binding. Our results demonstrate that phosphorothioate-modified ASOs bind a set of cellular proteins that affect ASO activity via different mechanisms.
                Bookmark

                Author and article information

                Journal
                Nucleic Acid Ther
                Nucleic Acid Ther
                nat
                Nucleic Acid Therapeutics
                Mary Ann Liebert, Inc. (140 Huguenot Street, 3rd FloorNew Rochelle, NY 10801USA )
                2159-3337
                2159-3345
                01 April 2017
                01 April 2017
                01 April 2017
                : 27
                : 2
                : 70-77
                Affiliations
                [1]Department of Core Antisense Research, Ionis Pharmaceuticals, Inc. , Carlsbad, California.
                Author notes
                Address correspondence to: Stanley T. Crooke, MD, PhD, Department of Core Antisense Research, Ionis Pharmaceuticals, Inc. 2855 Gazelle Court, Carlsbad, CA 92010, E-mail: scrooke@ 123456ionisph.com
                Article
                10.1089/nat.2016.0656
                10.1089/nat.2016.0656
                5372764
                28080221
                a7119dd3-193f-44be-8387-0f8d825b7fd3
                © Stanley T. Crooke, 2017; Published by Mary Ann Liebert, Inc.

                This Open Access article is distributed under the terms of the Creative Commons Attribution Noncommercial License ( http://creativecommons.org/licenses/by-nc/4.0/) which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.

                History
                : 25 October 2016
                : 14 December 2016
                Page count
                Figures: 2, References: 54, Pages: 8
                Categories
                Issues in Development

                rnase h,oligonucleotide,antisense,mechanisms,rna,dna
                rnase h, oligonucleotide, antisense, mechanisms, rna, dna

                Comments

                Comment on this article