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Kim JE, Kang MJ, Choi JY, Park JJ, Lee MR, Song BR, Kim HR, Park JW, Choi HJ, Bae SJ, Hwang DY. Regulation of gastrointestinal hormones during laxative activity of gallotannin-enriched extract isolated from Galla Rhois in loperamide-induced constipation of SD rats. Lab Anim Res 2018; 34:223-231. [PMID: 30671109 PMCID: PMC6333618 DOI: 10.5625/lar.2018.34.4.223] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/03/2018] [Accepted: 12/04/2018] [Indexed: 11/22/2022] Open
Abstract
Regulation of gastrointestinal hormones have been reported in animal models for constipation undergoing laxative therapy when administered herbal products. We undertook to investigate whether the laxative activity of gallotannin-enriched extracts isolated from Galla Rhois (GEGR) affects the regulation of gastrointestinal hormones, by examining the concentration of four hormones and the activation of their receptors in the loperamide (Lop)-induced constipation model. Stool parameters, including number, weight and water content, were significantly recovered in the Lop+GEGR treated group, relative to the Lop+vehicle treated group; however, food intake and water consumption were maintained at a constant level. Also, a similar recovery was detected for thickness of mucosa, muscle and flat luminal surface in the Lop+GEGR treated group. Furthermore, concentration of the four gastrointestinal hormones evaluated, namely, cholecystokinin (CCK), gastrin (GAS), somatostatin (SS) and motilin (MTL), were lower in the Lop+vehicle treated group than the No treated group, but were remarkably enhanced in the Lop+GEGR treated group. Moreover, the downstream signaling pathway of MTL and SS receptors were recovered after GEGR administration. Results of the present study therefore indicate that the laxative effects of GEGR treatment may be tightly related with the regulation of gastrointestinal hormones in the Lop-induced constipation model.
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Affiliation(s)
- Ji Eun Kim
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Mi Ju Kang
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Jun Young Choi
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Jin Ju Park
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Mi Rim Lee
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Bo Ram Song
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Hye Ryeong Kim
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Ji Won Park
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Hyeon Jun Choi
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Su Ji Bae
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Dae Youn Hwang
- Department of Biomaterials Science, College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
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2
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Recanati MA, Du H, Kramer KJ, Hüttemann M, Welch RA. Antisense techniques provide robust decrease in GnRH receptor expression with minimal cytotoxicity in GT1-7 cells. Syst Biol Reprod Med 2018; 64:389-398. [PMID: 30136857 DOI: 10.1080/19396368.2018.1499153] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The episodic pattern of gonadotropin-releasing hormone (GnRH) secretion from the hypothalamus is driven by an integrated network of cells termed the GnRH pulse generator. Cultured and immortalized GnRH neurons also produce a pulsatile pattern of GnRH secretions when grown in the absence of other cell types, suggesting the presence of an intrinsic oscillator mediating GnRH secretion. The mechanisms underlying such pulsatility comprise one of the most tantalizing problems in contemporary neuroendocrinology. In order to study the mechanism by which GnRH is produced in a pulsatile fashion, the autocrine effect of GnRH on GnRH-producing neurons must be eliminated. This may be performed by downregulating the expression of the GnRH receptor. Treatment with three 21-mer exogenous phosphorothioates and transient transfections with an inducible plasmid containing an antisense construct to the GnRH receptor gene decreased GnRH receptor expression further. This resulted in less cytotoxicity compared to inhibition of RNA or protein synthesis with actinomycin D, α-amanitin, puromycin, and cycloheximide. This study shows methods and optimized conditions established for the generation of a stable GT1-7 cell line containing an inducible construct allowing the downregulation of GnRH receptor expression. ABBREVIATIONS ANOVA: analysis of the variance; DMEM: Dulbecco's modified Eagle's medium; GnRH: gonadotropin-releasing hormone; RXR: retinoid X receptor.
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Affiliation(s)
| | - Hongling Du
- a Department of Obstetrics and Gynecology , Wayne State University , Detroit , MI , USA
| | | | - Maik Hüttemann
- c Center for Molecular Medicine and Genetics , Wayne State University , Detroit , MI , USA
| | - Robert A Welch
- a Department of Obstetrics and Gynecology , Wayne State University , Detroit , MI , USA
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3
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Kim JF, Gaffney PRJ, Valtcheva IB, Williams G, Buswell AM, Anson MS, Livingston AG. Organic Solvent Nanofiltration (OSN): A New Technology Platform for Liquid-Phase Oligonucleotide Synthesis (LPOS). Org Process Res Dev 2016. [DOI: 10.1021/acs.oprd.6b00139] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jeong F. Kim
- Department
of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ United Kingdom
| | - Piers R. J. Gaffney
- Department
of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ United Kingdom
| | - Irina B. Valtcheva
- Department
of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ United Kingdom
| | - Glynn Williams
- GlaxoSmithKline
Medicines Research Centre, Gunnels
Wood Road, Stevenage, Herts, SG1 2NY, United Kingdom
| | - Andrew M. Buswell
- GlaxoSmithKline
Medicines Research Centre, Gunnels
Wood Road, Stevenage, Herts, SG1 2NY, United Kingdom
| | - Mike S. Anson
- GlaxoSmithKline
Medicines Research Centre, Gunnels
Wood Road, Stevenage, Herts, SG1 2NY, United Kingdom
| | - Andrew G. Livingston
- Department
of Chemical Engineering, Imperial College London, Exhibition Road, London, SW7 2AZ United Kingdom
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4
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Williams A, Staroseletz Y, Zenkova MA, Jeannin L, Aojula H, Bichenkova EV. Peptidyl-oligonucleotide conjugates demonstrate efficient cleavage of RNA in a sequence-specific manner. Bioconjug Chem 2015; 26:1129-43. [PMID: 25955796 DOI: 10.1021/acs.bioconjchem.5b00193] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Described here is a new class of peptidyl-oligonucleotide conjugates (POCs) which show efficient cleavage of a target RNA in a sequence-specific manner. Through phosphoramidate attachment of a 17-mer TΨC-targeting oligonucleotide to amphiphilic peptide sequences containing leucine, arginine, and glycine, zero-linker conjugates are created which exhibit targeted phosphodiester cleavage under physiological conditions. tRNA(Phe) from brewer's yeast was used as a model target sequence in order to probe different structural variants of POCs in terms of selective TΨC-arm directed cleavage. Almost quantitative (97-100%) sequence-specific tRNA cleavage is observed for several POCs over a 24 h period with a reaction half-life of less than 1 h. Nontargeted cleavage of tRNA(Phe) or HIV-1 RNA is absent. Structure-activity relationships reveal that removal of the peptide's central glycine residue significantly decreases tRNA cleavage activity; however, this can be entirely restored through replacement of the peptide's C-terminal carboxylic acid group with the carboxamide functionality. Truncation of the catalytic peptide also has a detrimental effect on POC activity. Based on the encouraging results presented, POCs could be further developed with the aim of creating useful tools for molecular biology or novel therapeutics targeting specific messenger, miRNA, and genomic viral RNA sequences.
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Affiliation(s)
- Aled Williams
- †Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, United Kingdom, M13 9PT
| | - Yaroslav Staroseletz
- ‡Institute of Chemical Biology and Fundamental Medicine SB RAS, 8 Laurentiev Avenue, 630090, Novosibirsk, Russia
| | - Marina A Zenkova
- ‡Institute of Chemical Biology and Fundamental Medicine SB RAS, 8 Laurentiev Avenue, 630090, Novosibirsk, Russia
| | - Laurent Jeannin
- §Peptisyntha S.A., 310 Rue de Ransbeek, 1120 Brussels, Belgium
| | - Harmesh Aojula
- †Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, United Kingdom, M13 9PT
| | - Elena V Bichenkova
- †Manchester Pharmacy School, University of Manchester, Oxford Road, Manchester, United Kingdom, M13 9PT
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5
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Kim S, Min IM, Ren S, Spector A, Jin MM, Lis JT. Development of temperature-sensitive mutants of the Drosophila melanogaster P-TEFb (Cyclin T/CDK9) heterodimer using yeast two-hybrid screening. Biochem Biophys Res Commun 2013; 433:243-8. [PMID: 23500466 DOI: 10.1016/j.bbrc.2013.02.091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 02/28/2013] [Indexed: 10/27/2022]
Abstract
P-TEFb complex, a heterodimer of the kinase CDK9 and Cyclin T, is a critical factor that stimulates the process of transcription elongation. Here, we explored a fast and large-scale screening method to induce a temperature-dependent conditional disruption of the CDK9/Cyclin T interaction and developed an assay to validate their mutant phenotypes in a biological context. First, we used the yeast two-hybrid system to screen Drosophila melanogaster Cyclin T mutants at a large scale for temperature or cold sensitive (TS or CS) CDK9 interaction phenotypes. The isolated P-TEFb TS mutants were then expressed in Drosophila cells and were investigated for their effects on Drosophila hsp70 transcriptional activity. Our results showed that these P-TEFb TS mutants had a reduced level of hsp70 transcription at restrictive temperatures. A model structure of the Cyclin T and CDK9 complex suggested that the key TS mutations were found within the α2- and α3-helices at the interface of the complex, which may disrupt the binding of Cyclin T to CDK9 directly or indirectly by affecting the conformation of Cyclin T. The yeast two-hybrid-based screening strategy described here for isolating TS or CS interaction phenotypes can be directly applicable to other complexes in higher organisms. The use of TS or CS mutants will enable a 'real-time and reversible perturbation' restricted to specific protein-protein interactions, providing a mechanistic insight into the biological process mediated by a target complex.
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Affiliation(s)
- Soyoun Kim
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA.
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6
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7
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Byrne D, Daly C, Nicamhlaoibh R, Howlett A, Scanlon K, Clynes M. Use of ribozymes and antisense oligodeoxynucleotides to investigate mechanisms of drug resistance. Cytotechnology 2012; 27:113-36. [PMID: 19002787 DOI: 10.1023/a:1008052401952] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Chemotherapy can cure a number of human cancers but resistance (either intrinsic or acquired) remains a significant problem in many patients and in many types of solid tumour. Combination chemotherapy (using drugs with different cellular targets/mechanisms) was introduced in order to kill cells which had developed resistance to a specific drug, and to allow delivery of a greater total dose of anti-cancer chemicals by combining drugs with different side-effects (Pratt et al., 1994). Nearly all anti-cancer drugs kill tumour cells by activating an endogenous bio-chemical pathway for cell suicide, known as programmed cell death or apoptosis.
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Affiliation(s)
- D Byrne
- National Cell and Tissue Culture Centre, Dublin City University, Glasnevin, Dublin 9, Ireland
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8
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Carey MF, Peterson CL, Smale ST. Confirming the functional importance of a protein-DNA interaction. Cold Spring Harb Protoc 2012; 2012:733-57. [PMID: 22753608 DOI: 10.1101/pdb.top070060] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Identifying DNA-binding proteins that interact with a control region of interest has become quite straightforward. However, the functional relevance of a given protein-DNA interaction is difficult to establish. The hypothesis that an interaction is relevant can be tested by several different experiments, 12 of which are outlined in this article. It must be remembered that none of these experiments by itself is conclusive. The information gained from each approach is described and explanations are given for why each yields useful but inconclusive results. The approaches vary widely with respect to the amount of effort required and the quality of information obtained.
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9
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Sullivan JM, Yau EH, Kolniak TA, Sheflin LG, Taggart RT, Abdelmaksoud HE. Variables and strategies in development of therapeutic post-transcriptional gene silencing agents. J Ophthalmol 2011; 2011:531380. [PMID: 21785698 PMCID: PMC3138052 DOI: 10.1155/2011/531380] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2010] [Revised: 02/17/2011] [Accepted: 02/28/2011] [Indexed: 11/24/2022] Open
Abstract
Post-transcriptional gene silencing (PTGS) agents such as ribozymes, RNAi and antisense have substantial potential for gene therapy of human retinal degenerations. These technologies are used to knockdown a specific target RNA and its cognate protein. The disease target mRNA may be a mutant mRNA causing an autosomal dominant retinal degeneration or a normal mRNA that is overexpressed in certain diseases. All PTGS technologies depend upon the initial critical annealing event of the PTGS ligand to the target RNA. This event requires that the PTGS agent is in a conformational state able to support hybridization and that the target have a large and accessible single-stranded platform to allow rapid annealing, although such platforms are rare. We address the biocomplexity that currently limits PTGS therapeutic development with particular emphasis on biophysical variables that influence cellular performance. We address the different strategies that can be used for development of PTGS agents intended for therapeutic translation. These issues apply generally to the development of PTGS agents for retinal, ocular, or systemic diseases. This review should assist the interested reader to rapidly appreciate critical variables in PTGS development and facilitate initial design and testing of such agents against new targets of clinical interest.
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Affiliation(s)
- Jack M. Sullivan
- Department of Ophthalmology, University at Buffalo SUNY, Buffalo, NY 14214, USA
- Department of Pharmacology and Toxicology, University at Buffalo SUNY, Buffalo, NY 14214, USA
- Department of Physiology and Biophysics, University at Buffalo SUNY, Buffalo, NY 14214, USA
- Neuroscience Program, University at Buffalo SUNY, Buffalo, NY 14214, USA
- Ross Eye Institute, University at Buffalo SUNY, Buffalo, NY 14209, USA
- Veterans Administration Western New York Healthcare System, Medical Research, Buffalo, NY 14215, USA
| | - Edwin H. Yau
- Department of Ophthalmology, University at Buffalo SUNY, Buffalo, NY 14214, USA
- Department of Pharmacology and Toxicology, University at Buffalo SUNY, Buffalo, NY 14214, USA
| | - Tiffany A. Kolniak
- Department of Ophthalmology, University at Buffalo SUNY, Buffalo, NY 14214, USA
- Neuroscience Program, University at Buffalo SUNY, Buffalo, NY 14214, USA
| | - Lowell G. Sheflin
- Department of Ophthalmology, University at Buffalo SUNY, Buffalo, NY 14214, USA
- Veterans Administration Western New York Healthcare System, Medical Research, Buffalo, NY 14215, USA
| | - R. Thomas Taggart
- Department of Ophthalmology, University at Buffalo SUNY, Buffalo, NY 14214, USA
| | - Heba E. Abdelmaksoud
- Department of Neuroscience and Physiology, Upstate Medical University, Syracuse, NY 13215, USA
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10
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Lalonde MS, Lobritz MA, Ratcliff A, Chamanian M, Athanassiou Z, Tyagi M, Wong J, Robinson JA, Karn J, Varani G, Arts EJ. Inhibition of both HIV-1 reverse transcription and gene expression by a cyclic peptide that binds the Tat-transactivating response element (TAR) RNA. PLoS Pathog 2011; 7:e1002038. [PMID: 21625572 PMCID: PMC3098202 DOI: 10.1371/journal.ppat.1002038] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Accepted: 03/04/2011] [Indexed: 11/18/2022] Open
Abstract
The RNA response element TAR plays a critical role in HIV replication by
providing a binding site for the recruitment of the viral transactivator protein
Tat. Using a structure-guided approach, we have developed a series of
conformationally-constrained cyclic peptides that act as structural mimics of
the Tat RNA binding region and block Tat-TAR interactions at nanomolar
concentrations in vitro. Here we show that these compounds
block Tat-dependent transcription in cell-free systems and in cell-based
reporter assays. The compounds are also cell permeable, have low toxicity, and
inhibit replication of diverse HIV-1 strains, including both CXCR4-tropic and
CCR5-tropic primary HIV-1 isolates of the divergent subtypes A, B, C, D and
CRF01_AE. In human peripheral blood mononuclear cells, the cyclic peptidomimetic
L50 exhibited an IC50 ∼250 nM. Surprisingly, inhibition of
LTR-driven HIV-1 transcription could not account for the full antiviral
activity. Timed drug-addition experiments revealed that L-50 has a bi-phasic
inhibition curve with the first phase occurring after HIV-1 entry into the host
cell and during the initiation of HIV-1 reverse transcription. The second phase
coincides with inhibition of HIV-1 transcription. Reconstituted reverse
transcription assays confirm that HIV-1 (−) strand strong stop DNA
synthesis is blocked by L50-TAR RNA interactions in-vitro.
These findings are consistent with genetic evidence that TAR plays critical
roles both during reverse transcription and during HIV gene expression. Our
results suggest that antiviral drugs targeting TAR RNA might be highly effective
due to a dual inhibitory mechanism. The HIV-1 transactivator protein (Tat), together with the elongation factor
P-TEFb binds to an HIV-1 RNA secondary structure in the 5′-UTRs of nascent
viral mRNAs (TAR) and promotes transcription elongation. This process has been
an attractive target for drug development but previous inhibitors that bind
either Tat or TAR have been plagued by poor inhibition of virus replication,
limited cell penetration, and off-target effects. In this article, we describe a
series of rationally designed cyclic peptides that block Tat-TAR interactions.
L50, the most potent of these compounds, inhibits a wide range of HIV-1 strains
from around the world. Remarkably, L50 inhibits two distinct steps in the HIV-1
lifecycle. As expected, L50 inhibits Tat-dependent HIV-1 transcription, but the
majority of its anti-HIV activity is due to a block in reverse transcription,
i.e. synthesis of the proviral DNA from the RNA genome. L50 inhibition of
reverse transcription reveals an important role for TAR RNA during reverse
transcription as well as providing one of first examples of a drug with a dual
mechanism of action.
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Affiliation(s)
- Matthew S. Lalonde
- Department of Biochemistry, Case Western
Reserve University, Cleveland, Ohio, United States of America
| | - Michael A. Lobritz
- Department of Molecular Biology and
Microbiology, Case Western Reserve University, Cleveland, Ohio, United States of
America
| | - Annette Ratcliff
- Department of Molecular Biology and
Microbiology, Case Western Reserve University, Cleveland, Ohio, United States of
America
| | - Mastooreh Chamanian
- Department of Molecular Biology and
Microbiology, Case Western Reserve University, Cleveland, Ohio, United States of
America
| | - Zafiria Athanassiou
- Department of Chemistry and Department of
Biochemistry, University of Washington, Seattle, Washington, United States of
America
| | - Mudit Tyagi
- Department of Molecular Biology and
Microbiology, Case Western Reserve University, Cleveland, Ohio, United States of
America
| | - Julian Wong
- Department of Molecular Biology and
Microbiology, Case Western Reserve University, Cleveland, Ohio, United States of
America
| | - John A. Robinson
- Department of Chemistry, University of Zurich,
Zurich, Switzerland
| | - Jonathan Karn
- Department of Molecular Biology and
Microbiology, Case Western Reserve University, Cleveland, Ohio, United States of
America
| | - Gabriele Varani
- Department of Chemistry and Department of
Biochemistry, University of Washington, Seattle, Washington, United States of
America
| | - Eric J. Arts
- Department of Molecular Biology and
Microbiology, Case Western Reserve University, Cleveland, Ohio, United States of
America
- Division of Infectious Diseases, Department of
Medicine, Case Western Reserve University, Cleveland, Ohio, United States of
America
- * E-mail:
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11
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Xu J, Wang K, Zhang X, Qiu Y, Huang D, Li W, Xiao X, Tian Y. HSP70: a promising target for laryngeal carcinoma radiaotherapy by inhibiting cleavage and degradation of nucleolin. J Exp Clin Cancer Res 2010; 29:106. [PMID: 20691082 PMCID: PMC2928197 DOI: 10.1186/1756-9966-29-106] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Accepted: 08/06/2010] [Indexed: 12/12/2022] Open
Abstract
Previous studies have shown that heat shock proteins (HSPs) were upregulated in various types of tumors and were associated with histological grade, recurrence and metastasis of malignant tumors. In this study, we investigated whether heat shock protein 70 kDa (HSP70) was associated with histological grade of laryngeal squamous cell carcinomas (LSCC). We also determine the role of HSP70 in LSCC radiation resistance using a laryngeal carcinoma xenograft model by antisense HSP70 RNA technique. Immunohistochemistry data showed that HSP70 was detected in 96% of LSCC tissues (48 out of 50). The expression level of HSP70 was significantly lower in early stage of LSCC than that in late stage (P = 0.015). Radiation treatment result showed that the volumes and weights of implantation tumors in the group injected with antisense HSP70 oligos were significantly reduced comparing to the group injected with random oligos(p < 0.05). In addition, cleavage and degradation of tumor nucleolin in antisense HSP70 oligos injection group was significantly higher than that in random oligos injection group. Our result suggested that HSP70 may play a role in LSCC radiotherapy resistance by inhibiting cleavage and degradation of nucleolin.
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Affiliation(s)
- Jing Xu
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, PR China
| | - Kangkai Wang
- Department of Pathophysiology, Xiangya Hospital, Central South University, Changsha, PR China
| | - Xin Zhang
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, PR China
| | - Yuanzheng Qiu
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, PR China
| | - Donghai Huang
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, PR China
| | - Wei Li
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, PR China
| | - Xianzhong Xiao
- Department of Pathophysiology, Xiangya Hospital, Central South University, Changsha, PR China
| | - Yongquan Tian
- Department of Otolaryngology, Xiangya Hospital, Central South University, Changsha, PR China
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12
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Sipes TB, Freier SM. Prediction of antisense oligonucleotide efficacy using aggregate motifs. J Bioinform Comput Biol 2009; 6:919-32. [PMID: 18942159 DOI: 10.1142/s0219720008003795] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Revised: 10/13/2007] [Accepted: 02/11/2008] [Indexed: 11/18/2022]
Abstract
Antisense oligonucleotide technology allows the targeted reduction of mRNA expression through the in vitro application of short (approximately 20 nt) DNA molecules. Oligonucleotides are valuable both in the study of gene regulation and for having potential therapeutic effects. In theory, a base sequence complementary to a region of the transcript would hybridize to its mRNA target. Nevertheless, in practice some complementary antisense oligonucleotides are more active and more potent than others in suppressing specific gene expression. We present a novel computational approach to modeling oligonucleotide efficacy that uses aggregate motifs, which are flexible tetramotifs that expand the predictive ability of the data descriptors and the attribute space. We also demonstrate our findings on the largest dataset yet reported in the literature. It was shown that the prediction accuracy was significantly enhanced, offering more than eightfold improvement compared to the traditional methods.
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Affiliation(s)
- Tamara B Sipes
- SciberQuest, Inc., 777 South Highway 101, Suite 108, Solana Beach, CA 92075-2623, USA.
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13
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Paul A, Avci-Adali M, Neumann B, Guo K, Straub A, Dietz K, Ziemer G, Wendel HP. Aptamers influence the hemostatic system by activating the intrinsic coagulation pathway in an in vitro Chandler-Loop model. Clin Appl Thromb Hemost 2008; 16:161-9. [PMID: 19117958 DOI: 10.1177/1076029608329580] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
One class of oligonucleotides with a high potential for use in medical applications is short nucleic acids, widely known as aptamers. Although several aptamers are already being used clinically, there are very few studies dealing with the impact aptamers have on the hemostatic system. In this study, we have performed a comprehensive evaluation of the hemostatic system including coagulation, platelets, complement, and inflammatory activation by using different aptamer concentrations and fresh human whole blood in a well-established flow model. We found that single-stranded aptamers did not have a negative influence on platelets, complement, or inflammation but were able to activate factor XII, kallikrein, and prothrombin in a concentration-dependent manner. Consequently, the influence of aptamers on the coagulation system should be taken into consideration before the use of any aptamer-based drugs in patients.
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Affiliation(s)
- Angela Paul
- Department of Thoracic, Cardiac, and Vascular Surgery, University Hospital Tuebingen, Calwerstrasse 7/1, Tuebingen, Germany
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14
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Davis GL, Krawczynski K, Szabo G. Hepatitis C virus infection--pathobiology and implications for new therapeutic options. Dig Dis Sci 2007; 52:857-75. [PMID: 17333350 DOI: 10.1007/s10620-006-9484-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Accepted: 06/12/2006] [Indexed: 12/23/2022]
Abstract
Despite progress in therapeutic approaches for the elimination of hepatitis C, chronic hepatitis C virus infection remains an important cause of liver disease. Therapeutic intervention with the currently available interferon-based treatment regimens is quite successful, but treatment is difficult to tolerate and is contraindicated in many patients. A better understanding of the HCV biology, immunopathology, and liver disease will help to design better therapeutic strategies. The American Association for the Study of Liver Diseases sponsored a single-topic conference on hepatitis C virus infection on March 4 and 5, 2005, to enhance our current knowledge in the areas of basic and clinical research related to antiviral and immunomodulatory therapies in hepatitis C disease. The faculty consisted of 23 invited experts in the field of viral hepatitis. The program was divided into four sections including: (a) replicative mechanisms and models; (b) viral-host interactions; and (c) antiviral drug development and new strategies; and (d) back to the bedside-current issues. This report summarizes each of the presentations sections.
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Affiliation(s)
- Gary L Davis
- 4 Roberts, Hepatology, Baylor University Medical Center, 3500 Gaston Avenue, Dallas, TX 75246, USA.
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15
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Nadal A, Coll A, Cook N, Pla M. A molecular beacon-based real time NASBA assay for detection of Listeria monocytogenes in food products: role of target mRNA secondary structure on NASBA design. J Microbiol Methods 2007; 68:623-32. [PMID: 17258831 DOI: 10.1016/j.mimet.2006.11.011] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Revised: 11/06/2006] [Accepted: 11/20/2006] [Indexed: 11/20/2022]
Abstract
A molecular beacon-based real-time NASBA (QNASBA) assay for detection and identification of Listeria monocytogenes has been developed. A correlation between targeting highly accessible mRNA sequences and QNASBA efficiency and sensitivity was demonstrated. The assay targets a sequence from the mRNA transcript of the hly gene which is specific for this bacterium; and includes an internal amplification control to disclose failure of the reaction. It was fully selective and consistently detected down to 100 target molecules and 40 L. monocytogenes exponentially growing cells per reaction. In addition, it was capable of accurate quantification of target RNA molecules independently of the presence of DNA in the sample. In combination with a short RNase treatment prior to nucleic acids extraction our QNASBA specifically detected viable L. monocytogenes cells. It was successfully applied to rapid detection of this pathogen in meat and salmon products, and is therefore a useful tool for the study of L. monocytogenes in food samples. We finally discuss considerations of target secondary structure with regard to development of NASBA assays.
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Affiliation(s)
- Anna Nadal
- Institute of Food and Agricultural Technology, University of Girona, E-17071 Girona, Spain
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16
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Ueno Y, Ishihara S, Ito Y, Kitade Y. Synthesis and hybridization properties of oligonucleotides containing (2S,3R)-9-(2,3,4-trihydroxybutyl)adenine. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2006; 25:475-87. [PMID: 16838840 DOI: 10.1080/15257770600684175] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The synthesis and properties of oligonucleotides (ONs) containing 9-(2,3,4-trihydroxybutyl)adenine, A(C2) and A(C3), are described. The ON containing A(C2) involves the 3'-->4' and 3-->5' phosphodiester linkages in the strand, whereas that containing A(C3) possesses the 3'-->4' and 2'-->5' phosphodiester linkages. It was found that incorporation of the analogs, A(C2) or A(C3), into ONs significantly reduces the thermal and thermodynamic stabilities of the ON/DNA duplexes, but does not largely decrease the thermal and thermodynamic stabilities of the ON/RNA duplexes as compared with the case of the ON/DNA duplexes. It was revealed that the base recognition ability of A(C2) is greater than that of A(C3) in the ON/RNA duplexes.
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Affiliation(s)
- Yoshihito Ueno
- Department of Biomolecular Science, Faculty of Engineering, and Center for Emerging Infectious Diseases, Gifu University, Yanagido, Gifu, Japan
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17
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Glackin AJ, Gray SB, Johnston SR, Duggan BJ, Williamson KE. Antisense oligonucleotides in the treatment of bladder cancer. Expert Opin Biol Ther 2006; 5:67-77. [PMID: 15709910 DOI: 10.1517/14712598.5.1.67] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This review examines the role that antisense oligonucleotides play in the treatment of superficial and muscle-invasive bladder cancer. The unique environment of the urinary bladder allows intravesical instillation of antisense oligonucleotides, and researchers have already demonstrated uptake of antisense oligonucleotides in models of bladder cancer. Second, proof of principle has been established by demonstrating downregulation of the antisense target mRNA and protein. Third, and most importantly from a therapeutic perspective, synergy between chemotherapy and antisense oligonucleotides has been shown in bladder cancer models in vitro and in vivo. The collective evidence points to a role for antisense oligonucleotides in the treatment of superficial and muscle-invasive bladder cancer in combination with existing treatment modalities.
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Affiliation(s)
- Anthony J Glackin
- Queen's University Belfast, Uro-oncology Group, Institute of Pathology, Grosvenor Road, Belfast, BT12 6BN, Northern Ireland.
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18
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Affiliation(s)
- Paul D Berk
- The Division of Digestive Liver Diseases, Department of Medicine, Columbia University Medical Center, New York, NY
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19
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Nadal A, Eritja R, Esteve T, Pla M. "Parallel" and "antiparallel tail-clamps" increase the efficiency of triplex formation with structured DNA and RNA targets. Chembiochem 2005; 6:1034-42. [PMID: 15880676 DOI: 10.1002/cbic.200400358] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Sequence-specific triple-helix structures can be formed by parallel and antiparallel DNA clamps interacting with single-stranded DNA or RNA targets. Single-stranded nucleic acid molecules are known to adopt secondary structures that might interfere with intermolecular interactions. We demonstrate the correlation between a secondary structure involving the target--a stable stem predicted by in silico folding and experimentally confirmed by thermal stability and competition analyses--and an inhibitory effect on triplex formation. We overcame structural impediments by designing a new type of clamp: "tail-clamps". A combination of gel-shift, kinetic analysis, UV thermal melting and thermodynamic techniques was used to demonstrate that tail-clamps efficiently form triple helices with a structured target sequence. The performance of parallel and antiparallel tail-clamps was compared: antiparallel tail-clamps had higher binding efficiencies than parallel tail-clamps both with structured DNA and RNA targets. In addition, the reported triplex-stabilizing property of 8-aminopurine residues was confirmed for tail-clamps. Finally, we discuss the possible use of this improved triplex technology as a new tool for applications in molecular biology.
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Affiliation(s)
- Anna Nadal
- Departament de Genètica Molecular, Institut de Biologia Molecular de Barcelona, Consejo Superior de Investigaciones Científicas, Jordi Girona 18-26, 08034 Barcelona, Spain
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20
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Grammer M, Kuchay S, Chishti A, Baudry M. Lack of phenotype for LTP and fear conditioning learning in calpain 1 knock-out mice. Neurobiol Learn Mem 2005; 84:222-7. [PMID: 16150618 DOI: 10.1016/j.nlm.2005.07.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2005] [Revised: 07/23/2005] [Accepted: 07/28/2005] [Indexed: 10/25/2022]
Abstract
We previously proposed the hypothesis that calpain activation played an important role in long-term potentiation (LTP) of synaptic transmission in hippocampus. Two forms of calpain are predominant in brain tissues, calpain 1 (mu-calpain), activated by micromolar calcium concentration and calpain 2 (m-calpain), activated by millimolar calcium concentration in vitro. In the present study, we tested the role of calpain 1 in LTP and in learning and memory using calpain 1 knock-out mice. Changes in learning and memory were assessed using both context and tone fear conditioning. No differences in freezing responses were observed between the knock-out and the wild-type animals during the acquisition phase of the training, eliminating the possibility that the knock-out animals could be differentially affected by the foot shock. Likewise, no differences in freezing responses elicited by either the context or the tone were observed during the retention phase. No differences in short-term potentiation (STP) or LTP were observed in hippocampal slices from the knock-out and matched wild-type mice. Several interpretations might explain these negative results. First, it is conceivable that calpain 2 plays a more dominant role in neurons, and that calpain 1 makes a minor contribution as opposed to its suspected predominant role in the hematopoietic system. Alternatively, it is conceivable that some as yet unknown compensatory mechanisms take effect, and that calpain 2 or another calpain isoform substitutes for the missing calpain 1.
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Affiliation(s)
- Michael Grammer
- Neuroscience Program, University of Southern California, Los Angeles, CA 90089-2520, USA.
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21
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Vorobjev YN. Study of the Mechanism of Interaction of Oligonucleotides with the 3′-Terminal Region of tRNAPhe by Computer Modeling. Mol Biol 2005. [DOI: 10.1007/s11008-005-0093-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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22
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Famulok M, Mayer G. Intramers and aptamers: applications in protein-function analyses and potential for drug screening. Chembiochem 2005; 6:19-26. [PMID: 15637667 DOI: 10.1002/cbic.200400299] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Michael Famulok
- Rheinische Friedrich-Wilhelms Universität Bonn, Kekulé-Institut für Organische Chemie und Biochemie, Gerhard-Domagk-Strasse 1, 53121 Bonn, Germany.
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23
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Egger M, Porzig H, Niggli E, Schwaller B. Rapid turnover of the "functional" Na(+)-Ca2+ exchanger in cardiac myocytes revealed by an antisense oligodeoxynucleotide approach. Cell Calcium 2005; 37:233-43. [PMID: 15670870 DOI: 10.1016/j.ceca.2004.10.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2004] [Revised: 10/07/2004] [Accepted: 10/12/2004] [Indexed: 11/28/2022]
Abstract
Antisense oligodeoxynucleotides (AS-ODNs) were used in combination with transient functional expression of the cardiac Na(+)-Ca2+ exchanger (NCX1) to correlate suppression of the Na(+)-Ca2+ exchange function with down-regulation of NCX1 protein expression. In a de-novo expression system (Sf9 cells), a decrease in both, NCX1 mRNA and protein after AS-ODN application was paralleled by diminished NCX1 activity, a typical hallmark of a true "antisense effect". Although AS-ODN uptake was also efficient in rat neonatal cardiac myocytes, in whole-cell extracts of these cells treated with AS-ODNs, the amount of NCX1 protein determined in a quantitative binding assay remained almost unchanged, despite a prompt loss of NCX1 function. Immunocytochemical staining of myocytes revealed that most of the immunoreactivity was not localized in the plasma membrane, but in intracellular compartments and was barely affected by AS-ODN treatment. These results indicate that the "functional half-life" of the NCX1 protein in the plasma membrane of neonatal cardiac myocytes is surprisingly short, much shorter than reported half-lifes of about 30 h for other membrane proteins.
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Affiliation(s)
- Marcel Egger
- University of Bern, Department of Physiology, Bühlplatz 5, CH-3012 Bern, Switzerland.
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24
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Shen L, Zhang C, Ambrus JL, Wang JH. Silencing of human c-myc oncogene expression by poly-DNP-RNA. Oligonucleotides 2005; 15:23-35. [PMID: 15788898 DOI: 10.1089/oli.2005.15.23] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Deregulation of c-myc oncogene expression drives the progression of many different types of cancer. Recent experimental data suggest that even brief inhibition of c-myc expression may be sufficient to permanently stop tumor growth and induce regression of tumors. Previous efforts in developing an inhibitor to silence the c-myc gene were hampered by low efficacy and lack of sequence specificity. Here, we report the synthesis of an antisense RNA inhibitor based on a new 21-nt sequence on a poly- DNP-RNA platform that can specifically inhibit cancer cell growth by silencing c-myc gene expression. Both c-myc mRNA and protein levels were significantly decreased in MCF-7 cells following treatment with this antisense DNP-RNA inhibitor. The control compounds with sense or mismatched sequence were inactive. When c-myc transgenic mice were each treated with a single dose of the antisense RNA inhibitor, in vivo silencing of c-myc gene expression was observed for up to 72 hours by real-time RT-PCR. Similar treatment of c-myc transgenic mice with unmodified (native) homologous small interfering RNA (siRNA) had no effect on the mRNA concentration of the c-myc gene. Injection of this short antisense poly-DNP-RNA into mice did not induce the synthesis of DNP-binding immunoglobulins in the host. The observed in vivo gene silencing by this antisense RNA inhibitor suggests its possible use as a therapeutic agent for cancers involving the deregulation of c-myc gene expression.
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MESH Headings
- 2,4-Dinitrophenol/chemistry
- Animals
- Base Sequence
- Blotting, Western
- Cell Line, Tumor
- Cell Proliferation
- Codon, Initiator
- DNA/chemistry
- Dose-Response Relationship, Drug
- Enzyme-Linked Immunosorbent Assay
- Gene Expression Regulation
- Gene Silencing
- Genes, myc
- Genetic Therapy/methods
- Humans
- Immunoglobulin G/chemistry
- In Vitro Techniques
- Mice
- Mice, Inbred BALB C
- Mice, Transgenic
- Molecular Sequence Data
- Oligonucleotides, Antisense/chemistry
- Proto-Oncogene Proteins c-myc/genetics
- RNA/chemistry
- RNA, Messenger/chemistry
- RNA, Messenger/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
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Affiliation(s)
- Long Shen
- Bioenergetics Laboratory, Natural Sciences Complex, University at Buffalo, Buffalo, NY 14260, USA
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25
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Petyuk VA, Serikov RN, Vlassov VV, Zenkova MA. Hybridization of antisense oligonucleotides with alpha-sarcin loop region of Escherichia coli 23S rRNA. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2005; 23:895-906. [PMID: 15560079 DOI: 10.1081/ncn-200026038] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Binding of complementary oligonucleotides (ONs) with alpha-sarcin loop region (2638-2682) of Escherichia coli 23S rRNA was investigated. Four of the tested pentadecanucleotides efficiently bound to target sequences with association rate and equilibrium constants approximately 10(3) M(-1)s(-1) and 10(7) M(-1), respectively. ON S5 (CGAGAGGACCGGAGU) complementary to the sequence 2658-2672 displayed the highest affinity to the target. Activation energy for binding of ON S5 was measured to be 11 kcal/mol; this value corresponds to approximately 10% of the calculated enthalpy of the local RNA structure unfolding in the presence of this oligonucleotide. The activation energy value is evidence for the heteroduplex formation to occur via strand displacement pathway; the initiation of heteroduplex formation requires disruption of 1-2 base pairs in RNA hairpin.
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Affiliation(s)
- Vladislav A Petyuk
- Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
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26
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27
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Jason TLH, Koropatnick J, Berg RW. Toxicology of antisense therapeutics. Toxicol Appl Pharmacol 2004; 201:66-83. [PMID: 15519609 DOI: 10.1016/j.taap.2004.04.017] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2003] [Accepted: 04/28/2004] [Indexed: 12/24/2022]
Abstract
Targeting unique mRNA molecules using antisense approaches, based on sequence specificity of double-stranded nucleic acid interactions should, in theory, allow for design of drugs with high specificity for intended targets. Antisense-induced degradation or inhibition of translation of a target mRNA is potentially capable of inhibiting the expression of any target protein. In fact, a large number of proteins of widely varied character have been successfully downregulated using an assortment of antisense-based approaches. The most prevalent approach has been to use antisense oligonucleotides (ASOs), which have progressed through the preclinical development stages including pharmacokinetics and toxicological studies. A small number of ASOs are currently in human clinical trials. These trials have highlighted several toxicities that are attributable to the chemical structure of the ASOs, and not to the particular ASO or target mRNA sequence. These include mild thrombocytopenia and hyperglycemia, activation of the complement and coagulation cascades, and hypotension. Dose-limiting toxicities have been related to hepatocellular degeneration leading to decreased levels of albumin and cholesterol. Despite these toxicities, which are generally mild and readily treatable with available standard medications, the clinical trials have clearly shown that ASOs can be safely administered to patients. Alternative chemistries of ASOs are also being pursued by many investigators to improve specificity and antisense efficacy and to reduce toxicity. In the design of ASOs for anticancer therapeutics in particular, the goal is often to enhance the cytotoxicity of traditional drugs toward cancer cells or to reduce the toxicity to normal cells to improve the therapeutic index of existing clinically relevant cancer chemotherapy drugs. We predict that use of antisense ASOs in combination with small molecule therapeutics against the target protein encoded by the antisense-targeted mRNA, or an alternate target in the same or a connected biological pathway, will likely be the most beneficial application of this emerging class of therapeutic agent.
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Affiliation(s)
- Tracey L H Jason
- Cancer Research Laboratories, London Regional Cancer Centre, London, Ontario, Canada N6A 4L6
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28
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Adwan H, Bäuerle TJ, Berger MR. Downregulation of osteopontin and bone sialoprotein II is related to reduced colony formation and metastasis formation of MDA-MB-231 human breast cancer cells. Cancer Gene Ther 2004; 11:109-20. [PMID: 14647232 DOI: 10.1038/sj.cgt.7700659] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Osteopontin (OPN), bone sialoprotein (BSPII), and osteonectin (ON) belong to a family of glycoproteins, which have been linked to cancer metastasis and progression. Here, we report on the selection of antisense oligonucleotides (ASOs), which are effective in reducing their protein levels. In human MDA-MB-231 breast cancer cells, the maximum inhibition of protein expression ranged from 84% (OPN) to 75% (BSPII) and 70% (ON). Erucylphospho-NNN-trimethylpropanolamine (ErPC3) was used as positive control and combination partner. Exposure to ErPC3 inhibited colony formation of MDA-MB-231 cells by 11% (10 microM), 45% (14 microM) and 78% (20 microM). The clonogenicity of breast cancer cells was reduced by 15%, 11%, 8% (5 microM), 39%, 19%, 14% (10 microM) and 46%, 39%, 21% (20 microM) in response to ASO-OPN-04, ASO-BSPII-06 and ASO-ON-03, respectively. Combination of ErPC3 with the ASOs caused additive combination effects. Pre-exposure to the ASOs, but not to the NSO, inhibited formation of osteolytic metastasis in three of four (ASO-OPN-04, P<0.03) and two of four (ASO-BSPII-06) nude rats, and reduced metastasis lesions significantly (T/C%=4.3 and 9.1, P=0.05, respectively). We conclude that downregulation of OPN and BSPII reduces colony formation of MDA-MB-231 cells and formation of osteolytic metastasis in nude rats.
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Affiliation(s)
- Hassan Adwan
- Unit of Toxicology and Chemotherapy, Deutsches Krebsforschungszentrum Heidelberg, Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
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29
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Fuessel S, Kueppers B, Ning S, Kotzsch M, Kraemer K, Schmidt U, Meye A, Wirth MP. Systematic in vitro evaluation of survivin directed antisense oligodeoxynucleotides in bladder cancer cells. J Urol 2004; 171:2471-6. [PMID: 15126878 DOI: 10.1097/01.ju.0000116410.13874.b8] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
PURPOSE The rather poor responses to conventional treatment for bladder cancer (BCa) require novel, specific therapy approaches. The down-regulation of BCa associated genes may represent a new option to inhibit specifically BCa cell growth and induce cell death. Survivin, an apoptosis inhibitor that is up-regulated in the majority of malignancies, including BCa, provides an attractive target for molecular therapies, such as treatment with specific antisense oligode-oxynucleotides (AS-ODNs). MATERIALS AND METHODS We used mRNA secondary structure prediction to design survivin directed AS-ODNs. After lipid mediated transfection with 30 selected antisurvivin AS-ODN inhibitory effects on cell growth properties as well as on survivin expression were measured. RESULTS Three of 30 tested constructs reproducibly impaired the growth characteristics of 4 BCa cell lines. Detailed analysis of the cell line EJ28 treated with the constructs SVV261, SVV264 and SVV286 revealed a clear decrease in viability (down to 35%) and long-term proliferation (down to 14%), which were caused by cell cycle arrest and an increase in apoptosis (from 19.5% to 51.3% maximum). The inhibition of tumor cell growth was associated with up to 60% to 80% survivin expression down-regulation. Interestingly all 3 evolved AS-ODNs were directed against the putative single strand survivin mRNA motif between 274 to 285 nucleotides, identified by secondary structure prediction. The reported accessibility of this motif to other nucleic acid based inhibitors such as ribozymes and small interfering RNAs emphasizes the rationale of a systematic selection of mRNA target sites. CONCLUSIONS The survivin directed AS-ODNs shown to inhibit effectively the proliferation of BCa cells in the current study may provide suitable adjuvant therapeutic agents for the specific local treatment of BCa.
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Affiliation(s)
- Susanne Fuessel
- Department of Urology and Institute of Pathology, Technical University Dresden, Dresden, Germany.
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30
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Wang Q, Liu M, Kozasa T, Rothestein JD, Sternweis PC, Neubig RR. Ribozyme- and siRNA-Mediated Suppression of RGS-Containing RhoGEF Proteins. Methods Enzymol 2004; 389:244-65. [PMID: 15313570 DOI: 10.1016/s0076-6879(04)89015-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/21/2023]
Abstract
Given recent efforts to determine the sequence information on thousands of genes in the human genome, the current challenge is to identify the functions of these genes, including those encoding the regulator of G-protein signaling protein gene superfamily, and to establish their roles in particular signaling pathways in a native system. Increasingly, reverse genetic approaches are being used to address these questions. This article compares two powerful approaches [ribozyme and "short interfering" RNA (siRNA) techniques] under identical conditions for the first report on the suppression of endogenous RGS domain-containing RhoGEFs. The siRNA technique was found to be much more potent than ribozyme targeting at the same mRNA site of RGS-RhoGEFs. Also, the three siRNAs targeting LARG, PDZ-RhoGEF, and p115-RhoGEF are able to discriminate the closely related sequences within this RGS-RhoGEF gene family.
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Affiliation(s)
- Qin Wang
- Department of Pharmacology, University of Michigan, Ann Arbor 48109, USA
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31
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Abstract
It is well known that light resets the circadian clock only at specific times of day. The mechanisms mediating such gating of environmental input to the CNS are not well understood. We show that calbindinD28K (CalB)-containing cells of the suprachiasmatic nucleus (SCN), which are directly retinorecipient, gate photic entrainment of cellular circadian oscillators and thereby determine the timing of locomotor rhythmicity. Specifically, we demonstrate a circadian rhythm of subcellular localization of CalB: whereas the protein is detected at all times in the cytoplasm, it is low or absent in the nucleus during the night. Under normal circumstances, light-induced behavioral phase shifts and Period (Per) gene expression in the SCN occur only during the subjective night. Surprisingly, both behavioral phase shifts and light-induced Per are blocked during the subjective night and enhanced during the subjective day after administration of CalB antisense oligodeoxynucleotides. These results suggest a cellular basis for temporal gating of photic input to the circadian clock.
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32
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Michel T, Martinand-Mari C, Debart F, Lebleu B, Robbins I, Vasseur JJ. Cationic phosphoramidate alpha-oligonucleotides efficiently target single-stranded DNA and RNA and inhibit hepatitis C virus IRES-mediated translation. Nucleic Acids Res 2003; 31:5282-90. [PMID: 12954764 PMCID: PMC203318 DOI: 10.1093/nar/gkg733] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2003] [Revised: 07/24/2003] [Accepted: 07/24/2003] [Indexed: 12/29/2022] Open
Abstract
A potential means to improve the efficacy of steric-blocking antisense oligonucleotides (ON) is to increase their affinity for a target RNA. The grafting of cationic amino groups to the backbone of the ON is one way to achieve this, as it reduces the electrostatic repulsion between the ON and its target. We have examined the duplex stabilising effects of introducing cationic phosphoramidate internucleoside linkages into ON with a non-natural alpha-anomeric configuration. Cationic alpha-ON bound with high affinity to single-stranded DNA and RNA targets. Duplex stabilisation was proportional to the number of cationic modifications, with fully cationic ON having particularly high thermal stability. The average stabilisation was greatly increased at low ionic strength. The duplex formed between cationic alpha-ON and their RNA targets were not substrates for RNase H. The penalty in T(m) inflicted by a single mismatch, however, was high; suggesting that they are well suited as sequence-specific, steric-blocking, antisense agents. Using a well-described target sequence in the internal ribosome entry site of the human hepatitis C virus, we have confirmed this potential in a cell-free translation assay as well as in a whole cell assay. Interestingly, no vectorisation was necessary for the cationic alpha-ON in cell culture.
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Affiliation(s)
- Thibaut Michel
- Laboratoire de Chimie Organique Biomoléculaire de Synthèse, UMR 5625 CNRS-UMII, CC 008, Université Montpellier II, Place Eugène Bataillon, 34095 Montpellier Cedex 05, France
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33
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Collis SJ, Khater K, DeWeese TL. Novel therapeutic strategies in prostate cancer management using gene therapy in combination with radiation therapy. World J Urol 2003; 21:275-89. [PMID: 12920560 DOI: 10.1007/s00345-003-0363-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2003] [Accepted: 07/07/2003] [Indexed: 12/01/2022] Open
Affiliation(s)
- Spencer J Collis
- Department of Radiation Oncology and Molecular Radiation Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
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34
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Stone LS, Vulchanova L. The pain of antisense: in vivo application of antisense oligonucleotides for functional genomics in pain and analgesia. Adv Drug Deliv Rev 2003; 55:1081-112. [PMID: 12935946 DOI: 10.1016/s0169-409x(03)00105-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
As the genomic revolution continues to evolve, there is an increasing demand for efficient and reliable tools for functional characterization of individual gene products. Antisense oligonucleotide-mediated knockdown has been used successfully as a functional genomics tool in animal models of pain and analgesia yet skepticism regarding the validity and utility of antisense technology remains. Contributing to this uncertainty are the lack of systematic studies exploring antisense oligonucleotide use in vivo and the many technical and methodological challenges intrinsic to the method. This article reviews the contributions of antisense oligonucleotide-based studies to the field of pain and analgesia and the general principles of antisense technology. A special emphasis is placed on technical issues surrounding the successful application of antisense oligonucleotides in vivo, including sequence selection, antisense oligonucleotide chemistry, DNA controls, route of administration, uptake, dose-dependence, time-course and adequate evaluation of knockdown.
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Affiliation(s)
- Laura S Stone
- Department of Neuroscience, University of Minnesota, 6-125 Jackson Hall, 321 Church Street S.E., Minneapolis, MN 55455, USA.
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35
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Rizzo J, Gifford LK, Zhang X, Gewirtz AM, Lu P. Chimeric RNA-DNA molecular beacon assay for ribonuclease H activity. Mol Cell Probes 2003; 16:277-83. [PMID: 12270269 DOI: 10.1006/mcpr.2002.0423] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Current methods to detect and assay ribonuclease H (RNase H) activity are indirect and time-consuming. Here we introduce a direct and sensitive method, based on the fluorescence quenching mechanism of molecular beacons, to assay RNA cleavage in RNA:DNA hybrids. An RNA-DNA chimeric beacon assay for RNase H enzymatic activity was developed. The substrate is a single-stranded RNA-DNA chimeric oligonucleotide labeled with a 5'-fluorescein and a 3'-DABCYL. The fluorophore (fluorescein) of the probe is held in close proximity to the quencher (DABCYL) by the RNA:DNA stem-loop structure. When the RNA sequence of the RNA:DNA hybrid stem is cleaved, the fluorophore is separated from the quencher and fluorescence can be detected as a function of time. Chimeric beacons with different stem lengths and sequences have been surveyed for this assay with E. coli RNase H. We found that the beacon kinetic parameters are in qualitative agreement with previously reported values using more cumbersome assays. This method permits real-time detection of RNase H activity and a convenient approach to RNase H kinetic and mechanistic study.
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Affiliation(s)
- J Rizzo
- Department of Chemistry, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA, 19104, USA
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36
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Turowski P, Franckhauser C, Morris MC, Vaglio P, Fernandez A, Lamb NJC. Functional cdc25C dual-specificity phosphatase is required for S-phase entry in human cells. Mol Biol Cell 2003; 14:2984-98. [PMID: 12857880 PMCID: PMC165692 DOI: 10.1091/mbc.e02-08-0515] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
In view of the common regulatory mechanism that induces transcription of the mitotic phosphatase cdc25C and cyclin A at the beginning of S-phase, we investigated whether cdc25C was required for S-phase transit. Here, we show that in both nontransformed human fibroblasts and HeLa cells, cdc25C protein levels significantly increased concomitant with S-phase onset and cyclin A synthesis. Activity measurements on immunoprecipitates from synchronized HeLa cells revealed a sharp rise in cdc25C-associated phosphatase activity that coincided with S-phase. Microinjection of various antisense-cdc25C molecules led to inhibition of DNA synthesis in both HeLa cells and human fibroblasts. Furthermore, transfection of small interfering RNA directed against cdc25C specifically depleted cdc25C in HeLa cells without affecting cdc25A or cdc25B levels. Cdc25C RNA interference was also accompanied by S-phase inhibition. In cells depleted of cdc25C by antisense or siRNA, normal cell cycle progression could be re-established through microinjection of wild-type cdc25C protein but not inactive C377S mutant protein. Taken together, these results show that cdc25C not only plays a role at the G2/M transition but also in the modulation of DNA replication where its function is distinct from that of cdc25A.
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Affiliation(s)
- Patric Turowski
- Cell Biology Unit, Institut de Genetique Humaine, Centre National de la Recherche Scientifique Unité Mixte de Recherche 1142, F-34396 Montpellier, France
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37
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Abstract
The newly discovered phenomenon of RNA interference (RNAi) offers the dual facility of selective viral gene silencing coupled with ease of tailoring to meet genetic variation within the viral genome. Such promise identifies RNAi as an exciting new approach to treat viral-induced diseases, including viral-induced cancers (e.g. cervical carcinoma, hepatocellular carcinomas and haematopoietic and lymphoid malignancies). Cervical cancer is the second most common cancer in women worldwide and is caused by human papilloma virus (HPV). Silencing of HPV gene expression by RNAi induces apoptosis of cervical carcinoma cells in culture, and the effect is apparent within 3 days. The RNAi process is triggered by double-stranded RNA (dsRNA), and a single dose is sufficient to maintain RNAi for several days in vitro (cell culture) and in vivo (experimental animal models). Thus, the stage is set for the development of novel antiviral and anticancer therapies based upon selective gene silencing by RNA interference.
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Affiliation(s)
- Jo Milner
- Department of Biology, University of York, York, YO10 5DD, UK.
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Semizarov D, Frost L, Sarthy A, Kroeger P, Halbert DN, Fesik SW. Specificity of short interfering RNA determined through gene expression signatures. Proc Natl Acad Sci U S A 2003; 100:6347-52. [PMID: 12746500 PMCID: PMC164449 DOI: 10.1073/pnas.1131959100] [Citation(s) in RCA: 350] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2003] [Indexed: 11/18/2022] Open
Abstract
Short interfering RNA (siRNA) is widely used for studying gene function and holds great promise as a tool for validating drug targets and treating disease. A critical assumption in these applications is that the effect of siRNA on cells is specific, i.e., limited to the specific knockdown of the target gene. In this article, we characterize the specificity of siRNA by applying gene expression profiling. Several siRNAs were designed against different regions of the same target gene for three different targets. Their effects on cells were compared by using DNA microarrays to generate gene expression signatures. When the siRNA design and transfection conditions were optimized, the signatures for different siRNAs against the same target were shown to correlate very closely, whereas the signatures for different genes revealed no correlation. These results indicate that siRNA is a highly specific tool for targeted gene knockdown, establishing siRNA-mediated gene silencing as a reliable approach for large-scale screening of gene function and drug target validation.
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Affiliation(s)
- Dimitri Semizarov
- Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, IL 60064, USA.
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39
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Ito T, Ueno Y, Komatsu Y, Matsuda A. Synthesis, thermal stability and resistance to enzymatic hydrolysis of the oligonucleotides containing 5-(N-aminohexyl)carbamoyl-2'-O-methyluridines. Nucleic Acids Res 2003; 31:2514-23. [PMID: 12736300 PMCID: PMC156055 DOI: 10.1093/nar/gkg374] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The synthesis of oligonucleotides (ODNs) containing 5-(N-aminohexyl)carbamoyl-2'-O-methyluridine (D) is described, and thermal stability and resistance to enzymatic hydrolysis of the ODNs are compared with ODNs containing 5-(N-aminohexyl)carbamoyl-2'-deoxyuridine (H). The ODNs containing D and the complementary RNA demonstrated a duplex thermal stabilization of 0.4-3.9 degrees C per modification depending on the position and the number, while the ODNs containing H with the RNA showed slightly less effective thermal stabilization. Further more, the ODNs containing D were found to be more resistant to nucleolytic hydrolysis, not only by snake venom phosphodiesterase (SVPD; a 3'-exonuclease) but also by DNase I (an endonuclease). The half-life of the 17mer containing five molecules of D against nucleolytic hydrolysis by SVPD was 240 times greater than the unmodified 17mer ODN, which is 1.8 times greater than the ODN containing 5Hs in the same sequence. Against DNase I, the same ODN containing 5Ds was 24 times greater stable than the unmodified 17mer and 15 times more stable than the ODN containing 5Hs. We also examined whether the duplexes formed by the ODNs containing D and the complementary RNAs could be a substrate of Escherichia coli RNase H. It was revealed that a minimum of five contiguous unmodified 2'-deoxyribonucleosides between Ds was required to constitute a substrate of E.coli RNase H. Thus, the ODN with Ds and at least five contiguous unmodified 2'-deoxyribonucleosides between Ds was found to be a candidate for a novel antisense molecule.
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Affiliation(s)
- Takanori Ito
- Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812, Japan
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40
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Abstract
The base of knowledge concerning RNA structure and function has been expanding rapidly in recent years. Simultaneously, an increasing awareness of the pivotal role RNA plays in viral diseases has prompted many researchers to apply new technologies in high-throughput screening and molecular modelling to the design of antiviral drugs that target RNA. While the two RNA viruses with the greatest unmet medical need, HIV and HCV, have been most actively pursued, the approaches discussed in this review are relevant to all virus infections. Both traditional small-molecule and large-molecule therapeutics, such as antisense, ribozymes and interfering dsRNAs have been described, and several molecules are under development for commercialization. The purpose of this review is to summarize the current state of the art in this field and to postulate new directions in the future.
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MESH Headings
- Antiviral Agents/therapeutic use
- Base Sequence
- Drug Design
- Humans
- Models, Molecular
- Molecular Sequence Data
- Nucleic Acid Conformation
- Oligonucleotides, Antisense/genetics
- Oligonucleotides, Antisense/therapeutic use
- RNA, Antisense/genetics
- RNA, Antisense/therapeutic use
- RNA, Catalytic/genetics
- RNA, Catalytic/therapeutic use
- RNA, Viral/chemistry
- RNA, Viral/drug effects
- RNA, Viral/genetics
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Affiliation(s)
- Kevin L McKnight
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Ind., USA.
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41
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Rosas MF, Martínez-Salas E, Sobrino F. Stable expression of antisense RNAs targeted to the 5' non-coding region confers heterotypic inhibition to foot-and-mouth disease virus infection. J Gen Virol 2003; 84:393-402. [PMID: 12560572 DOI: 10.1099/vir.0.18668-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The antiviral potential of transcripts targeted to the non-coding regions (NCRs) of foot-and-mouth disease virus (FMDV) RNA have been studied during transient and constitutive expression in susceptible BHK-21 cells. Transient expression of antisense transcripts corresponding to the 5' and 3'NCRs, alone or in combination, confers specific inhibition of homologous (serotype C) virus infection in BHK-21 cells. Constitutive expression of antisense 5'NCR transcripts (5'AS) exerted higher levels of inhibition to homologous and heterologous (serotypes O, A, Asia, SAT 1, SAT 2 and SAT 3) FMDV infection, as estimated by a 10-fold reduction in virus titre in the supernatants from infected clones and by a plaque reduction assay. These inhibitions were also observed, albeit to a lesser extent, in clones stably expressing antisense 3'NCR transcripts. The antiviral response was specific for FMDV, as the picornavirus encephalomyocarditis virus was not inhibited in any of the transformed cell lines. In all cases, a correlation was found between the level of transcript expression and the extent of virus inhibition. The potential to efficiently inhibit FMDV, including isolates representing the seven serotypes, by expressing interfering 5'AS transcripts opens the possibility of developing transgenic animals with a reduced susceptibility to FMDV.
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Affiliation(s)
- M F Rosas
- Centro de Investigación en Sanidad Animal, INIA, Valdeolmos, 28130 Madrid, Spain
- Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Cantoblanco, 28049 Madrid, Spain
| | - E Martínez-Salas
- Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Cantoblanco, 28049 Madrid, Spain
| | - F Sobrino
- Centro de Investigación en Sanidad Animal, INIA, Valdeolmos, 28130 Madrid, Spain
- Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Cantoblanco, 28049 Madrid, Spain
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42
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Murphy D, Wells S. In vivo gene transfer studies on the regulation and function of the vasopressin and oxytocin genes. J Neuroendocrinol 2003; 15:109-25. [PMID: 12535153 DOI: 10.1046/j.1365-2826.2003.00964.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Novel genes can be introduced into the germline of rats and mice by microinjecting fertilized one-cell eggs with fragments of cloned DNA. A gene sequence can thus be studied within the physiological integrity of the resulting transgenic animals, without any prior knowledge of its regulation and function. These technologies have been used to elucidate the mechanisms by which the expression of the two genes in the locus that codes for the neuropeptides vasopressin and oxytocin is confined to, and regulated physiologically within, specific groups of neurones in the hypothalamus. A number of groups have described transgenes, derived from racine, murine and bovine sources, in both rat and mouse hosts, that mimic the appropriate expression of the endogenous vasopressin and genes in magnocellular neurones (MCNs) of the supraoptic and paraventricular nuclei. However, despite considerable effort, a full description of the cis-acting sequences mediating the regulation of the vasopressin-oxytocin locus remains elusive. Two general conclusions have nonetheless been reached. First, that the proximal promoters of both genes are unable to confer any cell-specific regulatory controls. Second, that sequences downstream of the promoter, within the structural gene and/or the intergenic region that separates the two genes, are crucial for appropriate expression. Despite these limitations, sufficient knowledge has been garnered to specifically direct the expression of reporter genes to vasopressin and oxytocin MCNs. Further, it has been shown that reporter proteins can be directed to the regulated secretory pathway, from where they are subject to appropriate physiological release. The use of MCN expression vectors will thus enable the study of the physiology of these neurones through the targeted expression of biologically active molecules. However, the germline transgenic approach has a number of limitations involving the interpretation of phenotypes, as well as the large cost, labour and time demands. High-throughput somatic gene transfer techniques, principally involving the stereotaxic injection of hypothalamic neuronal groups with replication-deficient adenoviral vectors, are now being developed that obviate these difficulties, and which enable the robust, long-lasting expression of biologically active proteins in vasopressin and oxytocin MCNs.
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Affiliation(s)
- D Murphy
- Molecular Neuroendocrinology Research Group, University of Bristol Research Centre for Neuroendocrinology, Bristol Royal Infirmary, Bristol, UK.
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43
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Ayre BG, Köhler U, Turgeon R, Haseloff J. Optimization of trans-splicing ribozyme efficiency and specificity by in vivo genetic selection. Nucleic Acids Res 2002; 30:e141. [PMID: 12490732 PMCID: PMC140090 DOI: 10.1093/nar/gnf141] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2002] [Revised: 10/09/2002] [Accepted: 10/20/2002] [Indexed: 11/14/2022] Open
Abstract
Trans-splicing ribozymes are RNA-based catalysts capable of splicing RNA sequences from one transcript specifically into a separate target transcript. In doing so, a chimeric mRNA can be produced, and new gene activities triggered in living cells dependent on the presence of the target mRNA. Based on this ability of trans-splicing ribozymes to deliver new gene activities, a simple and versatile plating assay was developed in Saccharomyces cerevisiae for assessing and optimizing constructs in vivo. Trans-splicing ribozymes were used to splice sequences encoding a GAL4-derived transcription activator into a target transcript from a prevalent viral pathogen. The transcription activator translated from this new mRNA in turn triggered the expression of genes under the regulatory control of GAL4 upstream-activating sequences. Two of the activated genes complemented metabolic deficiencies in the host strain, and allowed growth on selective media. A simple genetic assay based on phenotypic conversion from auxotrophy to prototrophy was established to select efficient and specific trans-splicing ribozymes from a ribozyme library. This simple assay may prove valuable for selecting optimal target sites for therapeutic agents such as ribozymes, antisense RNA and antisense oligodeoxyribonucleotides, and for optimizing the design of the therapeutic agents themselves, in higher eukaryotes.
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Affiliation(s)
- Brian G Ayre
- Plant Biology Department, Cornell University, Ithaca, NY 14853, USA and. Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.
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44
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Abstract
Non-natural, functional RNA molecules, such as short interfering (si) RNAs, aptazymes, maxizymes and intramers, allow modulation of gene function at the mRNA or protein level. This review discusses recent advances made in the expression and application of these functional RNAs and illustrates how engineered, intracellularly active RNAs can serve as promising tools for understanding the function of genes and their protein products or as potential therapeutic agents.
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Affiliation(s)
- Michael Famulok
- Institut für Biochemie, Rheinische Friedrich-Wilhelms-Universität Bonn, Gerhard-Domagk-Strasse 1, D-53121 Bonn, Germany.
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45
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Giddings MC, Shah AA, Freier S, Atkins JF, Gesteland RF, Matveeva OV. Artificial neural network prediction of antisense oligodeoxynucleotide activity. Nucleic Acids Res 2002; 30:4295-304. [PMID: 12364609 PMCID: PMC140555 DOI: 10.1093/nar/gkf557] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
An mRNA transcript contains many potential antisense oligodeoxynucleotide target sites. Identification of the most efficacious targets remains an important and challenging problem. Building on separate work that revealed a strong correlation between the inclusion of short sequence motifs and the activity level of an oligo, we have developed a predictive artificial neural network system for mapping tetranucleotide motif content to antisense oligo activity. Trained for high-specificity prediction, the system has been cross-validated against a database of 348 oligos from the literature and a larger proprietary database of 908 oligos. In cross- validation tests the system identified effective oligos (i.e. oligos capable of reducing target mRNA expression to <25% that of the control) with 53% accuracy, in contrast to the <10% success rates commonly reported for trial-and-error oligo selection, suggesting a possible 5-fold reduction in the in vivo screening required to find an active oligo. We have implemented a web interface to a trained neural network. Given an RNA transcript as input, the system identifies the most likely oligo targets and provides estimates of the probabilities that oligos targeted against these sites will be effective.
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Affiliation(s)
- Michael C Giddings
- Department of Human Genetics, University of Utah, SLC, UT 84112, USA and. Isis Pharmaceuticals, Carlsbad, CA 92008, USA.
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46
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Maclean N, Rahman MA, Sohm F, Hwang G, Iyengar A, Ayad H, Smith A, Farahmand H. Transgenic tilapia and the tilapia genome. Gene 2002; 295:265-77. [PMID: 12354662 DOI: 10.1016/s0378-1119(02)00735-7] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The tilapia fish (Oreochromis niloticus) has an important place in the aquaculture of the developing world. It is also a very useful laboratory animal, and readily lends itself to the transgenic technology. Through the use of reporter genes, a range of potential gene promoters have been tested in tilapia, both through transient and stable expression of the reporter construct. Using the transgenic technology, growth enhanced lines of tilapia have been produced. These fish have no abnormalities and offer a considerable growth advantage for future exploitation. It is however crucial that transgenic fish, to be exploited in aquaculture, be sterile, and various methods of achieving sterility are considered. These include triploidy, gene knock out of crucial hormone encoding genes via homologous recombination, and knock down of the function of the same genes via ribozyme or antisense technologies. Transgenic tilapia also offer the potential for exploitation as biofactories in the production of valuable pharmaceutical products, and this is also discussed.
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Affiliation(s)
- N Maclean
- Division of Cell Science, School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton SO16 7PX, UK.
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47
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McMahon BM, Stewart JA, Bitner MD, Fauq A, McCormick DJ, Richelson E. Peptide nucleic acids specifically cause antigene effects in vivo by systemic injection. Life Sci 2002; 71:325-37. [PMID: 12034350 DOI: 10.1016/s0024-3205(02)01647-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Peptide nucleic acids (PNAs) are uncharged DNA analogs that hybridize to complementary sequences with high affinity and stability. We previously showed that PNAs, after intraperitoneal injection into rats, are effective antisense compounds in vivo. The present study was designed to test whether PNAs also have antigene effects in vivo. The renin-angiotensin system is critical in the control of blood pressure. We designed and synthesized sense (antigene) PNAs to angiotensinogen, which is the precursor protein that leads to angiotensin I and II. Spontaneously hypertensive rats received intraperitoneal injections of either 20 mg/kg sense-angiotensinogen-PNA, mismatch-angiotensinogen PNA, or saline. Only the sense-angiotensinogen PNA treatment resulted in a significant decrease in plasma angiotensin I, systolic blood pressure, and liver and brain angiotensinogen mRNA levels. Thus, these results demonstrate on the molecular, protein, and physiological levels that antigene PNAs are effective in vivo upon systemic administration.
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Affiliation(s)
- Beth M McMahon
- Laboratory of Neuropsychopharmacology, Mayo Foundation for Medical and Educational Research, Jacksonville, FL 32224, USA.
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48
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Boye SM, Pradhan AAA, Grant RJ, Clarke PBS. Evidence for sequence-dependent and reversible nonspecific effects of PS-capped antisense treatment after intracerebral administration. ANTISENSE & NUCLEIC ACID DRUG DEVELOPMENT 2002; 12:95-102. [PMID: 12074369 DOI: 10.1089/108729002760070830] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Phosphorothioate (PS)-capped phosphodiester (PE) oligodeoxynucleotides (ODNs) were used to determine whether the dopamine-dependent locomotor-stimulant effect of nicotine is mediated via a4 subunit-containing nicotinic receptors. To this end, rats received direct intraventral tegmental area infusion of a4 antisense via osmotic minipump, and their locomotor response to nicotine (0.2 mg/kg, s.c.) was tested. Eight antisense ODNs were screened, but only one inhibited nicotine-induced locomotion. This inhibition was reversible and selective, insofar as basal (saline) activity was unaffected, and a mismatch ODN was without effect. However, antisense treatment also caused sequence-dependent toxic effects, including neuronal degeneration in the ventral tegmental area, dopaminergic denervation, and weight loss. We conclude that despite previous reports, PS-capped PE-ODNs can cause severe neurotoxicity on chronic infusion into brain tissue. Moreover, sequence dependence and temporal reversibility, two generally accepted criteria of antisense action, may sometimes reflect the occurrence of toxic effects and resultant functional compensation.
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Affiliation(s)
- Sandra M Boye
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada.
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49
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Papucci L, Schiavone N, Donnini M, Lapucci A, Luzi E, Tempestini A, Witort E, Capaccioli S. Phosphodiester oligonucleotides inhibit mitosis and trigger apoptosis by a non-antisense, p53-mediated mechanism. ANTISENSE & NUCLEIC ACID DRUG DEVELOPMENT 2002; 12:21-31. [PMID: 12022687 DOI: 10.1089/108729002753670238] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Oligodeoxyribonucleotides (ODNs) are currently employed to switch-off genes selectively routinely in the laboratory practice. The drawback of ODN application is that they have been often reported to elicit non-antisense effects by different mechanisms. Recently, it has been shown that double-stranded DNA oligonucleotides (30-mers) with protruding ends activate p53 in a cell-free system. In a previous work, we described that simple addition to the culture medium of heterogeneous DNA combined with cationic lipids culminated in inhibition of mitosis and induction of apoptosis. Here, we report that the same effects are achieved by lipotransfecting cultured cells with phosphorodiester ODNs (30-mers). Such effects of ODN were mediated by a non-antisense mechanism that required the wild-type form of the p53 oncosuppressor protein and was dependent on ODN concentration. Mitosis inhibition and apoptosis induction appeared to be determined by the 3' and 5' free ends of ODNs, which activated p53 independently from their sequence. Most probably, this mechanism is analogous to that evoked by genotoxic agent-induced DNA damage or by lipotransfecting cells with heterogeneous DNA.
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Affiliation(s)
- Laura Papucci
- Department of Experimental Pathology and Oncology, University of Florence, Italy.
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50
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Anselmet A, Mayat E, Wietek S, Layer PG, Payrastre B, Massoulié J. Non-antisense cellular responses to oligonucleotides. FEBS Lett 2002; 510:175-80. [PMID: 11801249 DOI: 10.1016/s0014-5793(01)03248-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Oligonucleotides induce various cellular responses which are not due to the blockade of protein synthesis by an antisense mechanism. Oligonucleotides presenting double-stranded or G-quartet structures (ribo- or deoxyribonucleotides, phosphodiester or phosphorothioated) induce retraction of neurites and aggregation of chicken retinal cells within 10-20 h. This effect is reversible, non-toxic; it appears to require internalization and can be mimicked by treatment of the cells with an RGDS peptide. The oligonucleotides appear to trigger a cascade of intracellular events, affecting the adhesive properties of integrins. In addition, a subset of oligonucleotides induced platelet aggregation, probably through their interaction with membrane receptors. Recognition of these effects is important for the design and interpretation of antisense experiments.
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Affiliation(s)
- Alain Anselmet
- CNRS UMR 8544, Laboratoire de Neurobiologie, Ecole Normale Supérieure, Paris, France.
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