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Webster GR, Teh AYH, Ma JKC. Synthetic gene design-The rationale for codon optimization and implications for molecular pharming in plants. Biotechnol Bioeng 2016; 114:492-502. [PMID: 27618314 DOI: 10.1002/bit.26183] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 08/10/2016] [Accepted: 09/05/2016] [Indexed: 12/14/2022]
Abstract
Degeneracy in the genetic code allows multiple codon sequences to encode the same protein. Codon usage bias in genes is the term given to the preferred use of particular synonymous codons. Synonymous codon substitutions had been regarded as "silent" as the primary structure of the protein was not affected; however, it is now accepted that synonymous substitutions can have a significant effect on heterologous protein expression. Codon optimization, the process of altering codons within the gene sequence to improve recombinant protein expression, has become widely practised. Multiple inter-linked factors affecting protein expression need to be taken into consideration when optimizing a gene sequence. Over the years, various computer programmes have been developed to aid in the gene sequence optimization process. However, as the rulebook for altering codon usage to affect protein expression is still not completely understood, it is difficult to predict which strategy, if any, will design the "optimal" gene sequence. In this review, codon usage bias and factors affecting codon selection will be discussed and the evidence for codon optimization impact will be reviewed for recombinant protein expression using plants as a case study. These developments will be relevant to all recombinant expression systems; however, molecular pharming in plants is an area which has consistently encountered difficulties with low levels of recombinant protein expression, and should benefit from an evidence based rational approach to synthetic gene design. Biotechnol. Bioeng. 2017;114: 492-502. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Gina R Webster
- Molecular Immunology Unit, Institute for Infection and Immunity, St. George's University of London, SW17 0RE, London, UK
| | - Audrey Y-H Teh
- Molecular Immunology Unit, Institute for Infection and Immunity, St. George's University of London, SW17 0RE, London, UK
| | - Julian K-C Ma
- Molecular Immunology Unit, Institute for Infection and Immunity, St. George's University of London, SW17 0RE, London, UK
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2
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RNase P-Mediated Sequence-Specific Cleavage of RNA by Engineered External Guide Sequences. Biomolecules 2015; 5:3029-50. [PMID: 26569326 PMCID: PMC4693268 DOI: 10.3390/biom5043029] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 10/16/2015] [Accepted: 10/29/2015] [Indexed: 01/06/2023] Open
Abstract
The RNA cleavage activity of RNase P can be employed to decrease the levels of specific RNAs and to study their function or even to eradicate pathogens. Two different technologies have been developed to use RNase P as a tool for RNA knockdown. In one of these, an external guide sequence, which mimics a tRNA precursor, a well-known natural RNase P substrate, is used to target an RNA molecule for cleavage by endogenous RNase P. Alternatively, a guide sequence can be attached to M1 RNA, the (catalytic) RNase P RNA subunit of Escherichia coli. The guide sequence is specific for an RNA target, which is subsequently cleaved by the bacterial M1 RNA moiety. These approaches are applicable in both bacteria and eukaryotes. In this review, we will discuss the two technologies in which RNase P is used to reduce RNA expression levels.
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3
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Sala CD, Soler-Bistué A, Bonomo R, Zorreguieta A, Tolmasky ME. External guide sequence technology: a path to development of novel antimicrobial therapeutics. Ann N Y Acad Sci 2015; 1354:98-110. [PMID: 25866265 PMCID: PMC4600001 DOI: 10.1111/nyas.12755] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Revised: 02/14/2015] [Accepted: 03/03/2015] [Indexed: 12/11/2022]
Abstract
RNase P is a ribozyme originally identified for its role in maturation of tRNAs by cleavage of precursor tRNAs (pre-tRNAs) at the 5'-end termini. RNase P is a ribonucleoprotein consisting of a catalytic RNA molecule and, depending on the organism, one or more cofactor proteins. The site of cleavage of a pre-tRNA is identified by its tertiary structure; and any RNA molecule can be cleaved by RNase P as long as the RNA forms a duplex that resembles the regional structure in the pre-tRNA. When the antisense sequence that forms the duplex with the strand that is subsequently cleaved by RNase P is in a separate molecule, it is called an external guide sequence (EGS). These fundamental observations are the basis for EGS technology, which consists of inhibiting gene expression by utilizing an EGS that elicits RNase P-mediated cleavage of a target mRNA molecule. EGS technology has been used to inhibit expression of a wide variety of genes, and may help development of novel treatments of diseases, including multidrug-resistant bacterial and viral infections.
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Affiliation(s)
- Carol Davies Sala
- Fundación Instituto Leloir, IIBBA-CONICET, and FCEyN, University of
Buenos Aires, Argentina
- Center for Applied Biotechnology Studies, College of Natural Sciences and
Mathematics, California State University Fullerton, Fullerton, California
| | - Alfonso Soler-Bistué
- Fundación Instituto Leloir, IIBBA-CONICET, and FCEyN, University of
Buenos Aires, Argentina
- Center for Applied Biotechnology Studies, College of Natural Sciences and
Mathematics, California State University Fullerton, Fullerton, California
| | - Robert Bonomo
- Department of Medicine, Case Western Reserve University School of Medicine,
Cleveland, Ohio
| | - Angeles Zorreguieta
- Fundación Instituto Leloir, IIBBA-CONICET, and FCEyN, University of
Buenos Aires, Argentina
| | - Marcelo E. Tolmasky
- Center for Applied Biotechnology Studies, College of Natural Sciences and
Mathematics, California State University Fullerton, Fullerton, California
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Yuan P, Ma R, Gao N, Garai M, Xu QH. Plasmon coupling-enhanced two-photon photoluminescence of Au@Ag core-shell nanoparticles and applications in the nuclease assay. NANOSCALE 2015; 7:10233-9. [PMID: 25990464 DOI: 10.1039/c5nr01409c] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Au and Ag nanoparticles (NPs) have been known to display significantly enhanced two-photon photoluminescence (2PPL) upon the formation of nanoparticle aggregates. The enhancement effect of the core-shell nanoparticles has not been explored so far. Here we have prepared Au@Ag bimetallic core-shell nanoparticles with different thicknesses (1.1, 2.1, 3.5, 4.5, and 5.5 nm) of silver coating on 19 nm Au NPs to investigate the composition effects on plasmon coupling-enhanced 2PPL. A maximum 2PPL enhancement factor (IcoupledNPs/IisolatedNPs) of up to 840-fold was obtained for Au@Ag NPs with ∼3.5 nm Ag nanoshells. These Au@Ag NPs were subsequently utilized in two-photon detection of S1 nuclease as a photoluminescence turn on probe. This method displayed high sensitivity with the limit of detection of 1.4 × 10(-6) U μL(-1) and an excellent selectivity.
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Affiliation(s)
- Peiyan Yuan
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543.
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Jiang XQ, Guo SM, Zhang M, Zhou M, Ye BC. DNA-hosted Hoechst dyes: application for label-free fluorescent monitoring of endonuclease activity and inhibition. Analyst 2014; 139:5682-5. [DOI: 10.1039/c4an01373e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lu L, Shiu-Hin Chan D, Kwong DWJ, He HZ, Leung CH, Ma DL. Detection of nicking endonuclease activity using a G-quadruplex-selective luminescent switch-on probe. Chem Sci 2014. [DOI: 10.1039/c4sc02032d] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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7
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A label-free DNA-templated silver nanocluster probe for fluorescence on–off detection of endonuclease activity and inhibition. Biosens Bioelectron 2014; 51:408-12. [DOI: 10.1016/j.bios.2013.07.060] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 07/21/2013] [Accepted: 07/23/2013] [Indexed: 01/03/2023]
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Xia C, Chen YC, Gong H, Zeng W, Vu GP, Trang P, Lu S, Wu J, Liu F. Inhibition of hepatitis B virus gene expression and replication by ribonuclease P. Mol Ther 2013; 21:995-1003. [PMID: 23481322 DOI: 10.1038/mt.2013.37] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Nucleic acid-based gene interfering approaches, such as those mediated by RNA interference and RNase P-associated external guide sequence (EGS), have emerged as promising antiviral strategies. The RNase P-based technology is unique, because a custom-designed EGS can bind to any complementary mRNA sequence and recruit intracellular RNase P for specific degradation of the target mRNA. In this study, a functional EGS was constructed to target hepatitis B virus (HBV) essential transcripts. Furthermore, an attenuated Salmonella strain was constructed and used for delivery of anti-HBV EGS in cells and in mice. Substantial reduction in the levels of HBV gene expression and viral DNA was detected in cells treated with the Salmonella vector carrying the functional EGS construct. Furthermore, oral inoculation of Salmonella carrying the EGS construct led to an inhibition of ~95% in the levels of HBV gene expression and a reduction of ~200,000-fold in viral DNA level in the livers and sera of the treated mice transfected with a HBV plasmid. Our results suggest that EGSs are effective in inhibiting HBV replication in cultured cells and mammalian livers, and demonstrate the use of Salmonella-mediated delivery of EGS as a promising therapeutic approach for human diseases including HBV infection.
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Affiliation(s)
- Chuan Xia
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, PR China
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Zhang Q, Kong DM. A general fluorescent sensor design strategy for “turn-on” activity detection of exonucleases and restriction endonucleases based on graphene oxide. Analyst 2013; 138:6437-44. [DOI: 10.1039/c3an01447a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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10
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Hongli L, Xukui L, Ting L, Wensheng L, Lusheng S, Jin Z. Transgenic tobacco expressed HPV16-L1 and LT-B combined immunization induces strong mucosal and systemic immune responses in mice. Hum Vaccin Immunother 2013; 9:83-9. [PMID: 23108357 PMCID: PMC3667950 DOI: 10.4161/hv.22292] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 09/09/2012] [Accepted: 09/19/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Although there are two HPV vaccines have been used to prevent cervical cancer, the cost limits their application in developing countries. The aim of this study was to evaluate the potential value of plant-based HPV16L1 and LTB proteins as a high-efficiency, low-cost and easy-to-use HPV16L1 oral vaccine. RESULTS Transgenic plant-derived HPV16L1 and LTB were identified, which display potent immunogenicity and biologic activity. Higher levels of specific IgG and IgA levels of HPV16L1 were induced when mice were immunized with L1 combined with LTB by the oral route. The stimulation index (SI) of spleen cells from the L1/LTB-immunized group was significantly higher than that in the L1-immunized group (p < 0.05). The percentage of IFN-γ (+) /IL-4 (+) CD4 (+) T cells from the L1/LTB group was clearly increased compared with that in the L1 and control groups (p < 0.05). METHODS Plant-expressed HPV16L1 and LTB proteins were extracted from transgenic tobacco leaves, and their biologic characteristics and activity were examined with electron microscopy and GM1-binding assays respectively. Mice were immunized orally with either HPV16L1 or LTB alone or in combination. Induced mucosal and systemic immune responses were detected by ELISA, Hemagglutination inhibition (HAI), lymphocyte proliferation assays and flow cytometry analysis. CONCLUSION Strong mucosal and systemic immune responses were induced by transgenic tobacco derived HPV16-L1 and LTB combined immunization. This study will lay the foundation for the development of a new type of vaccine to decrease HPV16 infections, which may lead to the prevention of cervical cancer.
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MESH Headings
- Adjuvants, Immunologic/administration & dosage
- Adjuvants, Immunologic/genetics
- Adjuvants, Immunologic/isolation & purification
- Administration, Oral
- Animals
- Antibodies, Viral/blood
- Bacterial Toxins/administration & dosage
- Bacterial Toxins/genetics
- Bacterial Toxins/isolation & purification
- Capsid Proteins/genetics
- Capsid Proteins/immunology
- Capsid Proteins/isolation & purification
- Cell Proliferation
- Enterotoxins/administration & dosage
- Enterotoxins/genetics
- Enterotoxins/isolation & purification
- Escherichia coli Proteins/administration & dosage
- Escherichia coli Proteins/genetics
- Escherichia coli Proteins/isolation & purification
- Female
- Flow Cytometry
- Immunity, Mucosal
- Immunoglobulin A/analysis
- Immunoglobulin G/analysis
- Immunoglobulin G/blood
- Interferon-gamma/metabolism
- Leukocytes, Mononuclear/immunology
- Mice
- Mice, Inbred BALB C
- Oncogene Proteins, Viral/genetics
- Oncogene Proteins, Viral/immunology
- Oncogene Proteins, Viral/isolation & purification
- Papillomavirus Vaccines/administration & dosage
- Papillomavirus Vaccines/genetics
- Papillomavirus Vaccines/immunology
- Papillomavirus Vaccines/isolation & purification
- Plants, Genetically Modified
- Recombinant Proteins/administration & dosage
- Recombinant Proteins/genetics
- Recombinant Proteins/immunology
- Recombinant Proteins/isolation & purification
- Spleen/immunology
- Nicotiana
- Vaccination/methods
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Affiliation(s)
- Liu Hongli
- First Affiliated Hospital of Medical College; Xi’an Jiaotong University; Xi’an, Shaanxi Province, P.R. China
| | - Li Xukui
- Stomatological Hospital of Medical College; Xi’an Jiaotong University; Xi’an, Shaanxi Province, P.R. China
| | - Lei Ting
- First Affiliated Hospital of Medical College; Xi’an Jiaotong University; Xi’an, Shaanxi Province, P.R. China
| | - Li Wensheng
- First Affiliated Hospital of Medical College; Xi’an Jiaotong University; Xi’an, Shaanxi Province, P.R. China
| | - Si Lusheng
- First Affiliated Hospital of Medical College; Xi’an Jiaotong University; Xi’an, Shaanxi Province, P.R. China
| | - Zheng Jin
- First Affiliated Hospital of Medical College; Xi’an Jiaotong University; Xi’an, Shaanxi Province, P.R. China
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11
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Jiang X, Chen YC, Gong H, Trang P, Lu S, Liu F. Ribonuclease P-mediated inhibition of human cytomegalovirus gene expression and replication induced by engineered external guide sequences. RNA Biol 2012; 9:1186-95. [PMID: 23018778 PMCID: PMC3579886 DOI: 10.4161/rna.21724] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
External guide sequences (EGSs) are RNA molecules that can bind to a target mRNA and direct ribonuclease P (RNase P), a tRNA processing enzyme, for specific cleavage of the target mRNA. Using an in vitro selection procedure, we have previously generated EGS variants that efficiently direct human RNase P to cleave a target mRNA in vitro. In this study, we constructed EGSs from a variant to target the overlapping region of the mRNAs coding for human cytomegalovirus (HCMV) capsid scaffolding protein (CSP) and assemblin, which are essential for viral capsid formation. The EGS variant was about 40-fold more active in directing human RNase P to cleave the mRNA in vitro than the EGS derived from a natural tRNA. Moreover, a reduction of about 98% and 75% in CSP/assemblin gene expression and a reduction of 7000- and 250-fold in viral growth were observed in HCMV-infected cells that expressed the variant and the tRNA-derived EGS, respectively. Our study shows that the EGS variant is more effective in blocking HCMV gene expression and growth than the tRNA-derived EGS. Moreover, these results demonstrate the utility of highly active EGS RNA variants in gene targeting applications including anti-HCMV therapy.
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Affiliation(s)
- Xiaohong Jiang
- School of Public Health; University of California; Berkeley, CA USA
- School of Life Sciences; Nanjing University; Nanjing, Jiangsu China
| | - Yuan-Chuan Chen
- Program in Comparative Biochemistry; University of California; Berkeley, CA USA
| | - Hao Gong
- School of Public Health; University of California; Berkeley, CA USA
| | - Phong Trang
- School of Public Health; University of California; Berkeley, CA USA
| | - Sangwei Lu
- School of Public Health; University of California; Berkeley, CA USA
- Program in Comparative Biochemistry; University of California; Berkeley, CA USA
| | - Fenyong Liu
- School of Public Health; University of California; Berkeley, CA USA
- Program in Comparative Biochemistry; University of California; Berkeley, CA USA
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Deng J, Jin Y, Wang L, Chen G, Zhang C. Sensitive detection of endonuclease activity and inhibition using gold nanorods. Biosens Bioelectron 2012; 34:144-50. [DOI: 10.1016/j.bios.2012.01.034] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 01/22/2012] [Accepted: 01/27/2012] [Indexed: 12/30/2022]
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Huang Y, Zhao S, Liang H, Chen ZF, Liu YM. Multiplex detection of endonucleases by using a multicolor gold nanobeacon. Chemistry 2011; 17:7313-9. [PMID: 21557352 DOI: 10.1002/chem.201003765] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2010] [Indexed: 12/21/2022]
Abstract
A highly sensitive and selective assay based on a novel enzyme-responsive multicolor gold nanobeacon has been developed for the multiplex detection of endonucleases, a group of very important nucleases. The nanobeacon takes advantage of the high specificity of DNA cleavage reactions combined with the unique fluorescence-quenching property of gold nanoparticles (AuNPs). To prepare the nanobeacon, three hairpin DNA reporters, each labeled at the 5' terminus with a fluorescent dye (i.e., fluorescein amidite (FAM), carboxy-X-rhodamine (ROX), cyanine dye (Cy5)), that respond to one of three different endonucleases are co-assembled at the surface of AuNPs (15 nm). This assembly brings the dyes into very close proximity with the AuNP, which leads to significant quenching of the fluorescence due to the nanosurface energy-transfer (NSET) effect. When the nanobeacon is exposed to the targeted endonucleases, specific DNA cleavage occurs and pieces of DNA fragments are released from the AuNP surface along with the fluorescent dye, which results in the fluorescence recovery that provides the basis for a quantitative measurement of endonuclease activity. Three endonucleases, namely HaeIII, EcoRI, and EcoRV, were studied as the proof-of-concept analytes. These endonucleases in homogeneous mixture solutions were simultaneously quantified by the proposed assay with high sensitivity and specificity. The limits of detection obtained were in the range of 5.0×10(-4) U mL(-1) to 1.0×10(-3) U mL(-1) of endonuclease; these limits are at least 100 times more sensitive than the previously reported endonuclease assays. Endonuclease inhibitors impair the DNA cleavage, so it is anticipated that the present method has great potential for screening inhibitors of endonucleases. To demonstrate this application, the inhibitory effects of certain anticancer drugs on HaeIII, EcoRI, and EcoRV activities were studied. The present protocol proved to be sensitive, reliable, and easy to carry out.
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Affiliation(s)
- Yong Huang
- Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources, College of Chemistry and Chemical Engineering, Guangxi Normal University, Guilin 541004, PR China
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14
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Liu PF, Nakatsuji T, Zhu W, Gallo RL, Huang CM. Passive immunoprotection targeting a secreted CAMP factor of Propionibacterium acnes as a novel immunotherapeutic for acne vulgaris. Vaccine 2011; 29:3230-8. [PMID: 21354482 DOI: 10.1016/j.vaccine.2011.02.036] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Revised: 01/31/2011] [Accepted: 02/12/2011] [Indexed: 02/07/2023]
Abstract
Propionibacterium acnes (P. acnes) bacteria play a key role in the pathogenesis of acne vulgaris. Although our previous studies have demonstrated that vaccines targeting a surface sialidase or bacterial particles exhibit a preventive effect against P. acnes, the lack of therapeutic activities and incapability of neutralizing secretory virulence factors motivate us to generate novel immunotherapeutics. In this study, we develop an immunotherapeutic antibody to secretory Christie-Atkins-Munch-Peterson (CAMP) factor of P. acnes. Via agroinfiltration, P. acnes CAMP factor was encapsulated into the leaves of radishes. ICR mice intranasally immunized with whole leaves expressing CAMP factor successfully produced neutralizing antibodies that efficiently attenuated P. acnes-induced ear swelling and production of macrophage-inflammatory protein-2. Passive neutralization of CAMP factor enhanced immunity to eradicate P. acnes at the infection site without influencing bacterial growth elsewhere. We propose that CAMP factor is a novel therapeutic target for the treatment of various P. acnes-associated diseases and highlight the concept of neutralizing P. acnes virulence without disturbing the bacterial commensalism in human microbiome.
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Affiliation(s)
- Pei-Feng Liu
- Department of Medicine, Division of Dermatology, University of California, San Diego, San Diego, CA 92121, USA
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Lu CH, Li J, Qi XJ, Song XR, Yang HH, Chen X, Chen GN. Multiplex detection of nucleases by a graphene-based platform. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm11121c] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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16
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Huang Y, Zhao S, Chen ZF, Liu YC, Liang H. Ultrasensitive endonuclease activity and inhibition detection using gold nanoparticle-enhanced fluorescence polarization. Chem Commun (Camb) 2011; 47:4763-5. [DOI: 10.1039/c1cc10325c] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Abstract
The ability to interfere with gene expression is of crucial importance to unravel the function of genes and is also a promising therapeutic strategy. Here we discuss methodologies for inhibition of target RNAs based on the cleavage activity of the essential enzyme, Ribonuclease P (RNase P). RNase P-mediated cleavage of target RNAs can be directed by external guide sequences (EGSs) or by the use of the catalytic M1 RNA from E. coli linked to a guide sequence (M1GSs). These are not only basic tools for functional genetic studies in prokaryotic and eukaryotic cells but also promising antibacterial, anticancer and antiviral agents.
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Affiliation(s)
- Eirik Wasmuth Lundblad
- Reference Centre for Detection of Antimicrobial Resistance, Department of Microbiology and Infection Control, University Hospital of North Norway, 9038 Tromsø, Norway.
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18
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Shan G. RNA interference as a gene knockdown technique. Int J Biochem Cell Biol 2009; 42:1243-51. [PMID: 19442757 DOI: 10.1016/j.biocel.2009.04.023] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2009] [Revised: 04/20/2009] [Accepted: 04/29/2009] [Indexed: 01/11/2023]
Abstract
Not many scientific breakthroughs bring significant advances simultaneously in both basic research and translational applications like the discovery of RNA interference. Along with the elucidation of the RNA interference pathway and the discovery of its participation in crucial biological events, a branch of science has grown to utilize the RNA interference pathway as a biotechnology for both basic and applied research. Small interference RNA, plasmid-, and virus-encoded short-hairpin RNA are now regular reagents in the tool box of biologists to knockdown the expression of specific genes posttranscriptionally. Efforts have also been made to develop RNA interference based therapeutics into reality. Many concerns about the RNA interference technique have now been answered through research and development, although hurdles are still present. In this review, the RNA interference/microRNA pathway is briefly introduced followed with a detailed summary about the design and application of the RNA interference experiments, along with examples of the utilization of the RNA interference technology in animal cells and model organisms. Recent progresses and current concerns are also highlighted. Two techniques, namely morpholino and external guide sequence, are discussed as complementary gene knockdown technology. RNA interference technology, along with several other alternative gene knockdown techniques, is now indispensable to modern biological and medical research.
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Affiliation(s)
- Ge Shan
- Department of Molecular, Cellular, and Developmental Biology, Yale University, P. O. Box 208103, New Haven, CT 06520, USA.
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Kim K, Liu F. Inhibition of gene expression in human cells using RNase P-derived ribozymes and external guide sequences. ACTA ACUST UNITED AC 2007; 1769:603-12. [PMID: 17976837 DOI: 10.1016/j.bbaexp.2007.09.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Revised: 09/13/2007] [Accepted: 09/14/2007] [Indexed: 11/19/2022]
Abstract
Ribonuclease P (RNase P) complexed with an external guide sequence (EGS) represents a novel nucleic acid-based gene interference approach to modulate gene expression. This enzyme is a ribonucleoprotein complex for tRNA processing. In Escherichia coli, RNase P contains a catalytic RNA subunit (M1 ribozyme) and a protein subunit (C5 cofactor). EGSs, which are RNAs derived from natural tRNAs, bind to a target mRNA and render the mRNA susceptible to hydrolysis by RNase P and M1 ribozyme. When covalently linked with a guide sequence, M1 can be engineered into a sequence-specific endonuclease, M1GS ribozyme, which cleaves any target RNAs that base pair with the guide sequence. Studies have demonstrated efficient cleavage of mRNAs by M1GS and RNase P complexed with EGSs in vitro. Moreover, highly active M1GS and EGSs were successfully engineered using in vitro selection procedures. EGSs and M1GS ribozymes are effective in blocking gene expression in both bacteria and human cells, and exhibit promising activity for antimicrobial, antiviral, and anticancer applications. In this review, we highlight some recent results using the RNase P-based technology, and offer new insights into the future of using EGS and M1GS RNA as tools for basic research and as gene-targeting agents for clinical applications.
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Affiliation(s)
- Kihoon Kim
- Program in Comparative Biochemistry, University of California, Berkeley, CA 94720, USA
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20
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Sabharwal N, Icoz I, Saxena D, Stotzky G. Release of the recombinant proteins, human serum albumin, beta-glucuronidase, glycoprotein B from human cytomegalovirus, and green fluorescent protein, in root exudates from transgenic tobacco and their effects on microbes and enzymatic activities in soil. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2007; 45:464-9. [PMID: 17467280 DOI: 10.1016/j.plaphy.2007.03.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2006] [Accepted: 03/08/2007] [Indexed: 05/15/2023]
Abstract
We determined the release in root exudates of human serum albumin (HSA), beta-glucuronidase (GUS), glycoprotein B (gB) from human cytomegalovirus, and green fluorescent protein (GFP) from genetically modified transgenic tobacco expressing the genes for these proteins in hydroponic culture and non-sterile soil. GUS, gB, and GFP were expressed in the plant but were not released in root exudates, whereas HSA was both expressed in the plant and released in root exudates, as shown by a 66.5-kDa band on SDS-PAGE and Western blot and confirmed by ELISA. Root exudates from GUS and gB plants showed no bands that could be attributed to these proteins on SDS-PAGE, and root exudates from GFP plants showed no fluorescence. The concentration of HSA in root exudates was estimated to be 0.021 ng ml(-1), whereas that in the plant biomass was estimated to be 0.087 ng ml(-1). The concentration of HSA in soil was estimated to be 0.049 ng g(-1). No significant differences in the number of microorganisms and the activity of selected enzymes were observed between rhizosphere soil of non-modified and HSA tobacco.
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Affiliation(s)
- N Sabharwal
- Laboratory of Microbial Ecology, Department of Biology, New York University, New York, NY 10003, USA
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21
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Lee MYT, Zhou Y, Lung RWM, Chye ML, Yip WK, Zee SY, Lam E. Expression of viral capsid protein antigen against Epstein-Barr virus in plastids of Nicotiana tabacum cv. SR1. Biotechnol Bioeng 2006; 94:1129-37. [PMID: 16586511 DOI: 10.1002/bit.20948] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Epstein-Barr virus (EBV) infects nearly 90% of adults worldwide and is the pathogenic source of a broad spectrum of malignancies originating from lymphoid and epithelial cells. Currently, no vaccine has been developed to immunologically inactivate this virus. In infected patients, anti-EBV viral capsid antigen (VCA) immunoglobins represent some of the useful diagnostic markers for carcinoma development. To demonstrate that the EBV VCA antigen can be produced in plants, the plastid genome of tobacco (Nicotiana tabacum cv. SR1) was transformed with a VCA-expressing cassette. The EBV VCA mRNA was actively transcribed in the transplastomic plants and antigen production was detected. This study indicates that plastid transformation could be a promising strategy in EBV VCA antigen production.
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Affiliation(s)
- Maggie Y T Lee
- Department of Botany, University of Hong Kong, Pokfulam Road, Hong Kong SAR, China
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22
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Nemchinov LG, Paape MJ, Sohn EJ, Bannerman DD, Zarlenga DS, Hammond RW. Bovine CD14 receptor produced in plants reduces severity of intramammary bacterial infection. FASEB J 2006; 20:1345-51. [PMID: 16816109 DOI: 10.1096/fj.05-5295com] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
CD14 is a high-affinity receptor protein for the complex of bacterial LPS (LPS) and LPS binding protein in animals. Binding of the soluble form of CD14 (sCD14) to LPS, found in the outer membrane of Escherichia coli and other Gram-negative bacteria, enhances host innate immune responses, reduces the severity of mastitis, and facilitates clearance and neutralization of LPS, thus protecting against an excessive immune response to LPS and development of endotoxic shock. A truncated form of sCD14, carrying a histidine residue affinity tag for purification, was incorporated into Potato virus X for transient expression in Nicotiana benthamiana plants. Western blots probed with CD14-specific antibodies demonstrated that crude plant extracts and affinity-purified samples contained immunoreactive sCD14. Biological activity of plant-derived recombinant bovine sCD14 (PrbosCD14) was demonstrated in vitro by LPS-induced apoptosis and interleukin (IL) -8 production in bovine endothelial cells, and in vivo by enhancement of LPS-induced neutrophil recruitment. Finally, in PrbosCD14-infused glands subsequently infected with E. coli, lower numbers of viable bacteria were recovered and there was an absence of clinical symptoms, demonstrating prophylactic efficacy of PrbosCD14. This is the first report of a functionally active animal receptor protein made in plants and the prophylactic use of a plant-derived protein to reduce the severity of bacterial infections in animals.
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Affiliation(s)
- Lev G Nemchinov
- USDA, ARS, Beltsville Agricultural Research Center, Beltsville, Maryland 20705, USA
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23
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Affiliation(s)
- Shengwu Ma
- Lawson Health Research Institute, Robarts Research Institute, Department of Biology, University of Western Ontario, London, ON, Canada N6A 5B8
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24
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Benimetskaya L, Stein CA. Antisense therapy: recent advances and relevance to prostate cancer. ACTA ACUST UNITED AC 2004; 1:20-30. [PMID: 15046709 DOI: 10.3816/cgc.2002.n.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Currently employed treatment options for patients with advanced and metastatic cancer such as surgery, radiation, hormone therapy, and chemotherapy are limited. In particular, the well known limitations of chemotherapy are at least in part due to a lack of specificity. The activation of dominant oncogenes and inactivation of tumor suppressor genes may represent novel targets for cancer therapy. Antisense therapy has been widely used to specifically and selectively inhibit the expression of selected genes at the messenger RNA level. Combinations of antisense oligonucleotides with chemotherapeutic agents may offer important advantages in cancer treatment. Several antisense drugs, especially oblimersen (G3139), have shown interesting results in experiments in animals, and have entered clinical trials. However, control oligonucleotides must be carefully chosen to separate antisense effects from the many potential nonspecific effects of oligonucleotides. This review summarizes the advantages and limitations of antisense therapy and its use in the treatment of androgen-independent prostate cancer.
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Affiliation(s)
- Luba Benimetskaya
- Department of Medicine, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA
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25
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Abstract
Plastids of higher plants are semi-autonomous organelles with a small, highly polyploid genome and their own transcription-translation machinery. This review provides an overview of the technology for the genetic modification of the plastid genome including: vectors, marker genes and gene design, the use of gene knockouts and over-expression to probe plastid function and the application of site-specific recombinases for excision of target DNA. Examples for applications in basic science include the study of plastid gene transcription, mRNA editing, photosynthesis and evolution. Examples for biotechnological applications are incorporation of transgenes in the plastid genome for containment and high-level expression of recombinant proteins for pharmaceutical and industrial applications. Plastid transformation is routine only in tobacco. Progress in implementing the technology in other crops is discussed.
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Affiliation(s)
- Pal Maliga
- Waksman Institute, Rutgers University, Piscataway, New Jersey 08854-8020, USA.
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26
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Abstract
Ribonuclease P (RNase P) is a ubiquitous ribonucleoprotein complex responsible for the biosynthesis of tRNA. This enzyme from Escherichia coli contains a catalytic RNA subunit (M1 ribozyme) and a protein subunit (C5 cofactor). M1 ribozyme cleaves an RNA helix that resembles the acceptor stem and T-stem structure of its natural tRNA substrate. When covalently linked with a guide sequence, M1 RNA can be engineered into a sequence-specific endonuclease, M1GS ribozyme, which can cleave any target RNA sequences that base pair with the guide sequence. Recent studies indicate that M1GS ribozymes efficiently cleave the mRNAs of herpes simplex virus 1, human cytomegalovirus, and cancer causing BCR-ABL proteins in vitro and effectively inhibit the expression of these mRNAs in cultured cells. Moreover, RNase P ribozyme variants that are more active than the wild type M1 RNA can be generated using in vitro selection procedures and the selected variants are also more effective in inhibiting gene expression in cultured cells. These results demonstrate that engineered RNase P ribozymes represent a novel class of promising gene-targeting agents for applications in both basic research and clinical therapy. This review discusses the principle underlying M1GS-mediated gene inactivation and methodologies involved in effective M1GS construction, expression in vivo and emerging prospects of this technology for gene therapy.
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Affiliation(s)
- Stephen M L Raj
- Division of Infectious Diseases, School of Public Health, University of California, Berkeley, CA 94720, USA
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27
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Kok-Jacon GA, Ji Q, Vincken JP, Visser RGF. Towards a more versatile alpha-glucan biosynthesis in plants. JOURNAL OF PLANT PHYSIOLOGY 2003; 160:765-777. [PMID: 12940545 DOI: 10.1078/0176-1617-01028] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Starch is an important storage polysaccharide in many plants. It is composed of densely packed alpha-glucans, consisting of 1,4- and 1,4,6-linked glucose residues. The starch polymers are used in many industrial applications. The biosynthetic machinery for assembling the granule has been manipulated in many different ways to gain insight into the process of starch biosynthesis and to engineer starches with improved functionalities. With respect to the latter, two generic technologies with great potential have been developed: (i) introduction of new linkage types in starch polymers (1,3- and 1,6-linkages), and (ii) engineering granule-boundness. The toolbox to engineer this new generation of starch polymers is discussed.
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28
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Tregoning JS, Nixon P, Kuroda H, Svab Z, Clare S, Bowe F, Fairweather N, Ytterberg J, van Wijk KJ, Dougan G, Maliga P. Expression of tetanus toxin Fragment C in tobacco chloroplasts. Nucleic Acids Res 2003; 31:1174-9. [PMID: 12582236 PMCID: PMC150239 DOI: 10.1093/nar/gkg221] [Citation(s) in RCA: 162] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2002] [Revised: 12/05/2002] [Accepted: 12/13/2002] [Indexed: 11/14/2022] Open
Abstract
Fragment C (TetC) is a non-toxic 47 kDa polypeptide fragment of tetanus toxin that can be used as a subunit vaccine against tetanus. Expression of TetC in Escherichia coli and yeast was dependent on the availability of synthetic genes that were required to improve translation efficiency and stabilize the mRNA. To explore the feasibility of producing TetC in tobacco leaves, we attempted expression of both the bacterial high-AT (72.3% AT) and the synthetic higher-GC genes (52.5% AT) in tobacco chloroplasts. We report here that the bacterial high-AT mRNA is stable in tobacco chloroplasts. Significant TetC accumulation was obtained from both genes, 25 and 10% of total soluble cellular protein, respectively, proving the versatility of plastids for expression of unmodified high-AT and high-GC genes. Mucosal immunization of mice with the plastid- produced TetC induced protective levels of TetC antibodies. Thus, expression of TetC in chloroplasts provides a potential route towards the development of a safe, plant-based tetanus vaccine for nasal and oral applications.
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Affiliation(s)
- John S Tregoning
- Waksman Institute, Rutgers University, 190 Frelinghuysen Road, Piscataway, NJ 08854-8020, USA
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29
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Awram P, Gardner RC, Forster RL, Bellamy AR. The potential of plant viral vectors and transgenic plants for subunit vaccine production. Adv Virus Res 2003; 58:81-124. [PMID: 12205784 DOI: 10.1016/s0065-3527(02)58003-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Peter Awram
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
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30
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Abstract
Tobacco chloroplasts are ready to be tested as a platform for the expression of recombinant proteins on a commercial scale. They hold the promise of reproducible yields of 5-25% of total soluble cellular protein in leaves and reliability has been achieved through refinement of an expression toolkit that includes vectors, recently developed expression cassettes and systems for marker gene removal. Implementation of plastid transformation technology in other crops, however, has met with difficulty and has delayed agronomic applications.
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Affiliation(s)
- Pal Maliga
- Waksman Institute, Rutgers, The State University of New Jersey, 190 Frelinghuysen Road, Piscataway, NJ 08854-8020, USA.
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31
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Abstract
The role of PKC isoforms in signal transduction pathways involved in regulation of the cell cycle, apoptosis, angiogenesis, differentiation, invasiveness, senescence and drug efflux are reviewed, along with the clinical results on the current crop of PKC inhibitors, including midostaurin (PKC-412, CGP 41251, N -benzoylstaurosporine), UCN-01 (7-hydroxystaurosporine), bryostatin 1, perifosine, ilmofosine, Ro 31-8220, Ro 32-0432, GO 6976, ISIS-3521 (CGP 64128A) and the macrocyclic bis (indolyl) maleimides (LY-333531, LY-379196, LY-317615). An appreciation of the complex, often contradictory roles of PKC isoforms in signal transduction pathways involved in cancer is important for interpreting the clinical results observed with PKC inhibitors of varying selectivity. An antisense oligonucleotide, ISIS-3521 and two orally available small molecule inhibitors, LY 333531 and midostaurin, have now advanced to latter stage development for cancer and/or other indications. These compounds have varying levels of selectivity for the PKC isoforms and for the kinase and initial safety and early clinical efficacy have been encouraging. At this stage, the potential of PKC inhibition for the treatment of cancer has not been fully realised. The concurrent inhibition of multiple PKC isoforms may yet provide an improved clinical outcome in treating cancers in view of the complex interrelated roles of the PKC isoforms.
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Affiliation(s)
- P G Goekjian
- Laboratoire Chimie Organique II/UMR 5622, Universite Claude Bernard Lyon 1; Bat. 308-CPE, 3 Rue Victor Grignard, 69622 Villeurbanne Cedex, France.
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32
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Chargelegue D, Obregon P, Drake PM. Transgenic plants for vaccine production: expectations and limitations. TRENDS IN PLANT SCIENCE 2001; 6:495-6. [PMID: 11701351 DOI: 10.1016/s1360-1385(01)02123-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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33
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Abstract
Transgenic plants are showing considerable potential for the economic production of proteins, with a few already being marketed. Recent clinical trials of pharmaceuticals produced from transgenic plants are encouraging, with plant glycans showing reassuringly poor immunogenicity. Our increasing understanding of protein targeting and accumulation should further improve the potential of this new technology.
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Affiliation(s)
- G Giddings
- Institute of Biological Sciences, Cledwyn Building, University of Wales Aberystwyth, Aberystwyth, SY23 3DD, Ceredigion, UK.
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34
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Abstract
Antisense oligonucleotides have been used for more than a decade to downregulate gene expression. Phosphodiester oligonucleotides are nuclease sensitive, and the more nuclease-resistant phosphorothioate oligonucleotides are now in common use in the laboratory and have entered clinical trials. However, these molecules are highly bioactive and may inhibit gene expression by more than one mechanism. Although some dramatic successes have been demonstrated, it can still be difficult to properly interpret experimental data derived from the use of this class of oligonucleotide. This review discusses some of these issues with particular reference to a major area of current interest--inhibition of bcl-2 expression in tumor cells.
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Affiliation(s)
- I Lebedeva
- College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA
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35
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Abstract
Antisense oligonucleotides have been the subject of intense interest as research tools to elucidate the functions of gene products and as therapeutic agents. Initially, their mode of action was poorly understood and the biological effects of oligonucleotides were often misinterpreted. However, research into these gene-based inhibitors of cellular action recently has succeeded in realising their exciting potential, particularly as novel therapeutic agents. An emerging application of this technology is in cutaneous therapy. The demand for more effective dermatological drugs will ensure further development of antisense strategies in skin, with key issues being drug delivery, therapeutic target selection, and clinical applicability.
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Affiliation(s)
- C J Wraight
- Centre for Hormone Research, Murdoch Childrens Research Institute, Flemington Road, Parkville, Victoria 3052, Australia.
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36
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Hilleman MR. Overview of the pathogenesis, prophylaxis and therapeusis of viral hepatitis B, with focus on reduction to practical applications. Vaccine 2001; 19:1837-48. [PMID: 11228353 DOI: 10.1016/s0264-410x(00)00364-9] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Hepatitis B is the most important of several hepatitis viruses of man because of the number of cases of the disease and the frequent occurrence of persistent infection that may lead to cirrhosis and cancer of the liver. The pathology of hepatitis B infection results mainly from the self-destructive cytotoxic T cell response of the host. This may be modulated by soluble pre-core e antigen of the virus that induces immune tolerance and by cytokines elaborated by cytotoxic T cells, which suppress viral replication in the infected cell. Pathogenesis of the disease is markedly influenced by viral mutations. Persistent hepatitis B virus infection may be controlled in a minority of patients by passive alpha-interferon therapy, and in a majority of patients by the nucleoside lamivudine until resistance develops. The best means to control the disease is by prevention through application of the highly effective vaccine prepared using surface antigen of the virus. It is anticipated that the gradually increasing application of the vaccine throughout the world may lead to elimination of hepatitis B as an important medical problem. This paper is intended to provide a cursory overview of the contemporary knowledge relating to pathogenesis, prophylaxis and therapeusis of human hepatitis B.
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37
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Galyam N, Grisaru D, Grifman M, Melamed-Book N, Eckstein F, Seidman S, Eldor A, Soreq H. Complex host cell responses to antisense suppression of ACHE gene expression. ANTISENSE & NUCLEIC ACID DRUG DEVELOPMENT 2001; 11:51-7. [PMID: 11258621 DOI: 10.1089/108729001750072128] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
3'-End-capped, 20-mer antisense oligodeoxynucleotides (AS-ODN) protected with 2'-O-methyl (Me) or phosphorothioate (PS) substitutions were targeted to acetylcholinesterase (AChE) mRNA and studied in PC12 cells. Me-modified AS-ODN suppressed AChE activity up to 50% at concentrations of 0.02-100 nM. PS-ODN was effective at 1-100 nM. Both AS-ODN displayed progressively decreased efficacy above 10 nM. In situ hybridization and confocal microscopy demonstrated dose-dependent decreases, then increases, in AChE mRNA. Moreover, labeling at nuclear foci suggested facilitated transcription or stabilization of AChE mRNA or both under AS-ODN. Intracellular concentrations of biotinylated oligonucleotide equaled those of target mRNA at extracellular concentrations of 0.02 nM yet increased only 6-fold at 1 microM ODN. Above 50 nM, sequence-independent swelling of cellular, but not nuclear, volume was observed. Our findings demonstrate suppressed AChE expression using extremely low concentrations of AS-ODN and attribute reduced efficacy at higher concentrations to complex host cell feedback responses.
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Affiliation(s)
- N Galyam
- Department of Biological Chemistry, The Institute of Life Sciences, The Hebrew University of Jerusalem, Israel
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38
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Trang P, Kilani A, Kim J, Liu F. A ribozyme derived from the catalytic subunit of RNase P from Escherichia coli is highly effective in inhibiting replication of herpes simplex virus 1. J Mol Biol 2000; 301:817-26. [PMID: 10966788 DOI: 10.1006/jmbi.2000.4022] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A sequence-specific ribozyme (M1GS RNA) derived from the catalytic RNA subunit of RNase P from Escherichia coli was used to target the mRNA encoding human herpes simplex virus 1 (HSV-1) major transcription activator, ICP4. A reduction of more than 80% in the expression level of ICP4 and a reduction of about 1000-fold in viral growth were observed in cells that stably expressed the ribozyme. In contrast, a reduction of less than 10 % in ICP4 expression and viral growth was observed in cells that either did not express the ribozyme or produced a catalytically inactive ribozyme mutant. Thus, M1GS ribozyme is highly effective in inhibiting HSV-1 growth and can be used as a general gene-targeting agent for anti-HSV applications.
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MESH Headings
- Animals
- Antiviral Agents/chemistry
- Antiviral Agents/metabolism
- Base Sequence
- Catalytic Domain
- Cell Line
- Endoribonucleases/chemistry
- Endoribonucleases/genetics
- Endoribonucleases/metabolism
- Escherichia coli/enzymology
- Escherichia coli/genetics
- Escherichia coli Proteins
- Gene Expression Regulation, Viral
- Gene Silencing
- Genes, Viral/genetics
- Herpesvirus 1, Human/growth & development
- Herpesvirus 1, Human/physiology
- Humans
- Immediate-Early Proteins/antagonists & inhibitors
- Immediate-Early Proteins/genetics
- Immediate-Early Proteins/metabolism
- RNA, Catalytic/chemistry
- RNA, Catalytic/genetics
- RNA, Catalytic/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Viral/genetics
- RNA, Viral/metabolism
- Ribonuclease P
- Substrate Specificity
- Transcription Factors/antagonists & inhibitors
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Transfection
- Virus Replication
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Affiliation(s)
- P Trang
- Program in Infectious Diseases and Immunity, Program in Comparative Biochemistry School of Public Health, University of California, 140 Warren Hall, Berkeley, CA 94720, USA
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