脱氧核酶在生物检测及基因治疗中的研究进展
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摘要
脱氧核酶(DNA zyme)是通过体外筛选技术获得的有酶活性的单链DNA分子.随着越来越多的脱氧核酶被筛选出来,科学家对其功能性质的研究也逐渐深入.其中,RNA切割作用作为脱氧核酶最重要的一种特性,是目前研究热点.而脱氧核酶发挥RNA切割作用需要辅因子(金属离子、中性分子、细菌等),因此,基于此特性,DNAzyme不仅被广泛用于金属离子和生物分子检测,而且被应用于特异性切割mRNA阻断蛋白的翻译,从而用于多类临床疾病的治疗.本文系统总结了DNAzyme在金属离子和生物分子检测以及在基因治疗方面的研究进展,并对其在动物体内对目标分子的高灵敏度、低浓度特异性检测及发挥切割活性进而达到疾病治疗做出了展望.
Catalytic DNA molecules(DNAzymes), produced through the systematic evolution of ligands by exponential enrichment(SELEX) process, are synthetic, single-stranded DNA molecules that either have catalytic abilities or can perform specific reactions. Among these DNAzymes, RNA-cleaving DNAzymes are the ones that can cleave RNAs at specific sites with the help of cofactors. The cofactors contains heavy metal ions(eg., Pb~(2+), Mg~(2+), Cu~(2+)), small molecules(eg., ATP, L-histidine, Vc), bacteria(eg., Escherichia coli) and so on. Based on the particular property, the RNA-cleaving DNAzymes are particularly promising for creating methods that can detect a wide variety of targets. For example, scientists have successfully found the Pb~(2+) DNAzyme, Cu~(2+) DNAzyme, UO_2~(2+) DNAzyme and some other specific metal ions.based DNAzymes. These DNAzymes have a high recognition specificity for the metal ions. Only when the specific metal ions existed, can the catalytic activity be performed. Besides, and the size of the catalytic activity is closely related to the concentration of metal ions. Therefore, these DNAzymes can be used to detect heavy metal ions. Similarly, the DNAzymes have been used to detect the ATP, L-histidine and Escherichia coli. What should be mentioned is that natural DNAzymes are generally D-type nucleic acids, which can be easily degraded by proteinase in physiological fluid. Therefore, in order to extend the applications of DNAzymes, emphasis has been placed on improving the selectivity and stability of DNAzymes. Based on the principle of enantiomer of nucleic acid, non-natural L-type nucleic acids have been used to prepare DNAzymes. L-type DNAzymes have similar thermal stability to D-DNAzymes, they also have better biostability and are ideal materials for constructing biosensors for complex system detection. Furthermore, based on the property of cleaving RNAs at specific sites, the DNAzymes can not only be used to detection, but also can be used to inactivate target cellular mRNA, which can be further applied in the treatment of multiple clinical disease. However, in fact, the gene therapy of DNAzymes in tumor and pathogenic microorganisms is only active in the scientific research stage, there is still a long way to realize the real clinical applications. The most prominent problem is the delivery problems, that is, how to choose a safe, efficient and specific guiding carrier to deliver DNAzyme to the target gene. In recent years, the rise of nanomedicine has brought new opportunities for gene therapy. The use of nano-sized materials to construct the drug delivery system can effectively deliver genetic drugs to tumor tissues. Nano drug carrier is an effective means to improve drug bioavailability, enhance drug stability and improve drug targeted therapy. In this review, we summarized the researches on DNAzyme-based metal ion sensors and gene treatment, and in the basis, we also outlook the possibility that whether the DNAzymes can be efficiently used to specifically detect the targets in vivo, as well as their applications of diseases therapy.
Catalytic DNA molecules(DNAzymes), produced through the systematic evolution of ligands by exponential enrichment(SELEX) process, are synthetic, single-stranded DNA molecules that either have catalytic abilities or can perform specific reactions. Among these DNAzymes, RNA-cleaving DNAzymes are the ones that can cleave RNAs at specific sites with the help of cofactors. The cofactors contains heavy metal ions(eg., Pb~(2+), Mg~(2+), Cu~(2+)), small molecules(eg., ATP, L-histidine, Vc), bacteria(eg., Escherichia coli) and so on. Based on the particular property, the RNA-cleaving DNAzymes are particularly promising for creating methods that can detect a wide variety of targets. For example, scientists have successfully found the Pb~(2+) DNAzyme, Cu~(2+) DNAzyme, UO_2~(2+) DNAzyme and some other specific metal ions.based DNAzymes. These DNAzymes have a high recognition specificity for the metal ions. Only when the specific metal ions existed, can the catalytic activity be performed. Besides, and the size of the catalytic activity is closely related to the concentration of metal ions. Therefore, these DNAzymes can be used to detect heavy metal ions. Similarly, the DNAzymes have been used to detect the ATP, L-histidine and Escherichia coli. What should be mentioned is that natural DNAzymes are generally D-type nucleic acids, which can be easily degraded by proteinase in physiological fluid. Therefore, in order to extend the applications of DNAzymes, emphasis has been placed on improving the selectivity and stability of DNAzymes. Based on the principle of enantiomer of nucleic acid, non-natural L-type nucleic acids have been used to prepare DNAzymes. L-type DNAzymes have similar thermal stability to D-DNAzymes, they also have better biostability and are ideal materials for constructing biosensors for complex system detection. Furthermore, based on the property of cleaving RNAs at specific sites, the DNAzymes can not only be used to detection, but also can be used to inactivate target cellular mRNA, which can be further applied in the treatment of multiple clinical disease. However, in fact, the gene therapy of DNAzymes in tumor and pathogenic microorganisms is only active in the scientific research stage, there is still a long way to realize the real clinical applications. The most prominent problem is the delivery problems, that is, how to choose a safe, efficient and specific guiding carrier to deliver DNAzyme to the target gene. In recent years, the rise of nanomedicine has brought new opportunities for gene therapy. The use of nano-sized materials to construct the drug delivery system can effectively deliver genetic drugs to tumor tissues. Nano drug carrier is an effective means to improve drug bioavailability, enhance drug stability and improve drug targeted therapy. In this review, we summarized the researches on DNAzyme-based metal ion sensors and gene treatment, and in the basis, we also outlook the possibility that whether the DNAzymes can be efficiently used to specifically detect the targets in vivo, as well as their applications of diseases therapy.
引文
1 Lander E S,Linton L M,Birren B,et al.Initial sequencing and analysis of the human genome.Nature,2001,409:860-921
2 Wang R E,Zhang Y,Cai J,et al.Aptamer-based fluorescent biosensors.Curr Med Chem,2011,18:4175-4184
3 Achenbach J C,Chiuman W,Cruz R P,et al.Dnazymes:From creation in vitro to application in vivo.Curr Pharm Biotechnol,2004,5:321-336
4 Silverman S K.In vitro selection,characterization,and application of deoxyribozymes that cleave RNA.Nucleic Acids Res,2005,33:6151
5 Wang F,Lu C H,Willner I.From cascaded catalytic nucleic acids to enzyme-DNA nanostructures:Controlling reactivity,sensing,logic operations,and assembly of complex structures.Chem Rev,2014,114:2881-2941
6 Sullenger B A,Gilboa E.Emerging clinical applications of RNA.Nature,2002,418:252-258
7 Pelossof G,Tel-Vered R,Willner I.Amplified surface plasmon resonance and electrochemical detection of Pb2+ions using the Pb2+-dependent dnazyme and hemin/g-quadruplex as a label.Anal Chem,2012,84:3703-3709
8 Needleman H.Lead poisoning.Annu Rev Med,2004,55:209-222
9 Baker A S,Deiters A.Optical control of protein function through unnatural amino acid mutagenesis and other optogenetic approaches.ACS Chem Biol,2014,9:1398-1407
10 Kumar B N,Venkata Ramana D K,Harinath Y,et al.Separation and preconcentration of Cd(ii),Cu(ii),Ni(ii),and Pb(ii)in water and food samples using amberlite XAD-2 functionalized with 3-(2-nitrophenyl)-1H-1,2,4-triazole-5(4H)-Thione and determination by inductively coupled plasma-Atomic emission spectrometry.J Agric Food Chem,2011,59:11352-11358
11 Wegner S V,Okesli A,Chen P,et al.Design of an emission ratiometric biosensor from MerR family proteins:A sensitive and selective sensor for Hg2+.J Am Chem Soc,2007,129:3474-3475
12 Peng X,Du J,Fan J,et al.A selective fluorescent sensor for imaging Cd2+in living cells.J Am Chem Soc,2007,129:1500-1501
13 Vester B,Wengel J.LNA(locked nucleic acid):High-affinity targeting of complementary RNA and DNA.Biochemistry,2004,43:13233-13241
14 Yang H,Zhou Z,Huang K,et al.Multisignaling optical-electrochemical sensor for Hg2+based on a rhodamine derivative with a ferrocene unit.Org Lett,2007,9:4729-4732
15 Breaker R R,Joyce G F.A DNA enzyme that cleaves RNA.Chem Biol,1994,1:223
16 Olea C Jr,Horning D P,Joyce G F.Ligand0dependent exponential amplification of a self-replicating l-RNA enzyme.J Am Chem Soc,2012,134:8050-8053
17 Lu L M,Zhang X B,Kong R M,et al.A ligation-triggered dnazyme cascade for amplified fluorescence detection of biological small molecules with zero-background signal.J Am Chem Soc,2011,133:11686-11691
18 Liu X,Tang Y,Wang L,et al.Optical detection of mercury(ii)in aqueous solutions by using conjugated polymers and label-free oligonucleotides.Adv Mater,2007,19:1471-1474
19 Liu J W,Lu Y.Adenosine-dependent assembly of aptazyme-functionalized gold nanoparticles and its application as a colorimetric biosensor.Anal Chem,2004,76:1627-1632
20 Liu J,Lu Y.Improving fluorescent dnazyme biosensors by combining inter-and intramolecular quenchers.Anal Chem,2003,75:6666-6672
21 Zhang X B,Wang Z,Xing H,et al.Catalytic and molecular beacons for amplified detection of metal ions and organic molecules with high sensitivity.Anal Chem,2010,82:5005-5011
22 Li H,Zhang Q,Cai Y,et al.Single-stranded dnazyme-based Pb2+fluorescent sensor that can work well over a wide temperature range.Bios Bioelectr,2012,34:159-164
23 Xu W T,Tian J J,Luo Y B,et al.A rapid and visual turn-off sensor for detecting copper(II)ion based on DNAzyme coupled with HCR-based HRP concatemers.Sci Rep,2017,7:43362
24 Liu J,Lu Y.A dnazyme catalytic beacon sensor for paramagnetic Cu2+ions in aqueous solution with high sensitivity and selectivity.JAm Chem Soc,2007,129:9838-9839
25 Li H,Huang X X,Kong D M,et al.Ultrasensitive,high temperature and ionic strength variation-tolerant Cu2+fluorescent sensor based on reconstructed Cu2+-dependent dnazyme/substrate complex.Biosens Bioelectron,2013,42:225-228
26 Cui L,Peng R,Fu T,et al.Biostable l-DNAzyme for sensing of metal ions in biological systems.Anal Chem,2016,88:1850-1855
27 Liu J W,Lu Y.A colorimetric lead biosensor using DNAzyme-directed assembly of gold nanoparticles.J Am Chem Soc,2003,125:6642-6643
28 Mei S H J,Liu Z J,Brennan J D,et al.An efficient RNA-cleaving DNA enzyme that synchronizes catalysis with fluorescence signaling.J Am Chem Soc,2003,125:412-420
29 Kandadai S A,Li Y.Characterization of a catalytically efficient acidic RNA-cleaving deoxyribozyme.Nucleic Acids Res,2005,33:7164-7175
30 Ali M M,Kandadai S A,Li Y.Characterization of ph3dz1-An RNA-cleaving deoxyribozyme with optimal activity at pH 3.Can JChem,2007,85:261-273
31 Aguirre S D,Ali M M,Kanda P,et al.Detection of bacteria using fluorogenic dnazymes.J Vis Exp,2012,3961
32 Ali M M,Aguirre S D,Lazim H,et al.Fluorogenic dnazyme probes as bacterial indicators.Angew Chem,2011,50:3751-3754
33 Zhang W,Feng Q,Chang D,et al.In vitro selection of RNA-cleaving dnazymes for bacterial detection.Methods,2016,106:66-75
34 Yousefi H,Ali M M,Su H M,et al.Sentinel wraps:Real-time monitoring of food contamination by printing dnazyme probes on food packaging.ACS Nano,2018,12:3287-3294
35 He S,Qu L,Shen Z,et al.Highly specific recognition of breast tumors by an RNA-cleaving fluorogenic dnazyme probe.Anal Chem,2015,87:569-577
36 Shahsavar K,Hosseini M,Shokri E,et al.A sensitive colorimetric aptasensor with a triple-helix molecular switch based on peroxidase-like activity of a dnazyme for ATP detection.Anal Methods,2017,9:4726-4731
37 Xu J,Wei C.The aptamer DNA-templated fluorescence silver nanoclusters:ATP detection and preliminary mechanism investigation.Biosens Bioelectron,2017,87:422-427
38 Lu L,Si J C,Gao Z F,et al.Highly selective and sensitive electrochemical biosensor for atp based on the dual strategy integrating the cofactor-dependent enzymatic ligation reaction with self-cleaving DNAzyme-amplified electrochemical detection.Biosens Bioelectron,2015,63:14-20
39 Kong R M,Zhang X B,Chen Z,et al.Unimolecular catalytic DNA biosensor for amplified detection of l-histidine via an enzymatic recycling cleavage strategy.Anal Chem,2011,83:7603-7607
40 He J L,Wu P,Zhu S L,et al.Cleaved dnazyme substrate induced enzymatic cascade for the exponential amplified analysis of l-histidine.Talanta,2015,132:809-813
41 Jiao X X,Nian H Q,Li B.Fabrication of graphene-gold nanocomposites by electrochemical co-reduction.J Electroanal Chem,2013,691:83-89
42 Baum D A,Silverman S K.Deoxyribozymes:Useful DNA catalysts in vitro and in vivo.Cellular Mol Life Sci,2008,65:2156-2174
43 Dass C R,Choong P F,Khachigian L M.DNAzyme technology and cancer therapy:Cleave and let die.Mol Cancer Ther,2008,7:243-251
44 Cairns M J,Hopkins T M,Witherington C,et al.The influence of arm length asymmetry and base substitution on the activity of the10-23 DNA enzyme.Antis Nucl A,2000,10:323-332
45 Wu Y,Yu L,McMahon R,et al.Inhibition of BCR-ABL oncogene expression by novel deoxyribozymes(DNAzymes).Hum Gene Ther,1999,10:2847-2857
46 Fan H,Zhang X,Lu Y.Recent advances in DNAzyme-based gene silencing.Sci China Chem,2017,60:591-601
47 Fan H,Zhao Z,Yan G,et al.A smart DNAzyme-MnO2 nanosystem for efficient gene silencing.Angew Chem,2015,54:4801-4805
48 Santoro S W,Joyce G F.A general purpose RNA-cleaving DNA enzyme.Proc Natl Acad Sci USA,1997,94:4262-4266
49 Unwalla H,Banerjea A C.Novel mono-and di-DNA-enzymes targeted to cleave TAT or TAT-REV RNA inhibit HIV-1 gene expression.Antiviral Res,2001,51:127-139
50 Unwalla H,Banerjea A.Inhibition of HIV-1 gene expression by novel macrophage-tropic DNA enzymes targeted to cleave HIV-1TAT/rev RNA.Biochem J,2001,357:147-155
51 Jing M X,Hong Y,Rao Y F,et al.Inhibition on hepatitis b virus e-gene expression of 10-23 DNAzyme delivered by.Carbohyd Polym,2012,87:1342-1347
52 Schubert S.Rna cleaving“10-23”DNAzymes with enhanced stability and activity.Nucl Acids Res,2003,31:5982-5992
2 Wang R E,Zhang Y,Cai J,et al.Aptamer-based fluorescent biosensors.Curr Med Chem,2011,18:4175-4184
3 Achenbach J C,Chiuman W,Cruz R P,et al.Dnazymes:From creation in vitro to application in vivo.Curr Pharm Biotechnol,2004,5:321-336
4 Silverman S K.In vitro selection,characterization,and application of deoxyribozymes that cleave RNA.Nucleic Acids Res,2005,33:6151
5 Wang F,Lu C H,Willner I.From cascaded catalytic nucleic acids to enzyme-DNA nanostructures:Controlling reactivity,sensing,logic operations,and assembly of complex structures.Chem Rev,2014,114:2881-2941
6 Sullenger B A,Gilboa E.Emerging clinical applications of RNA.Nature,2002,418:252-258
7 Pelossof G,Tel-Vered R,Willner I.Amplified surface plasmon resonance and electrochemical detection of Pb2+ions using the Pb2+-dependent dnazyme and hemin/g-quadruplex as a label.Anal Chem,2012,84:3703-3709
8 Needleman H.Lead poisoning.Annu Rev Med,2004,55:209-222
9 Baker A S,Deiters A.Optical control of protein function through unnatural amino acid mutagenesis and other optogenetic approaches.ACS Chem Biol,2014,9:1398-1407
10 Kumar B N,Venkata Ramana D K,Harinath Y,et al.Separation and preconcentration of Cd(ii),Cu(ii),Ni(ii),and Pb(ii)in water and food samples using amberlite XAD-2 functionalized with 3-(2-nitrophenyl)-1H-1,2,4-triazole-5(4H)-Thione and determination by inductively coupled plasma-Atomic emission spectrometry.J Agric Food Chem,2011,59:11352-11358
11 Wegner S V,Okesli A,Chen P,et al.Design of an emission ratiometric biosensor from MerR family proteins:A sensitive and selective sensor for Hg2+.J Am Chem Soc,2007,129:3474-3475
12 Peng X,Du J,Fan J,et al.A selective fluorescent sensor for imaging Cd2+in living cells.J Am Chem Soc,2007,129:1500-1501
13 Vester B,Wengel J.LNA(locked nucleic acid):High-affinity targeting of complementary RNA and DNA.Biochemistry,2004,43:13233-13241
14 Yang H,Zhou Z,Huang K,et al.Multisignaling optical-electrochemical sensor for Hg2+based on a rhodamine derivative with a ferrocene unit.Org Lett,2007,9:4729-4732
15 Breaker R R,Joyce G F.A DNA enzyme that cleaves RNA.Chem Biol,1994,1:223
16 Olea C Jr,Horning D P,Joyce G F.Ligand0dependent exponential amplification of a self-replicating l-RNA enzyme.J Am Chem Soc,2012,134:8050-8053
17 Lu L M,Zhang X B,Kong R M,et al.A ligation-triggered dnazyme cascade for amplified fluorescence detection of biological small molecules with zero-background signal.J Am Chem Soc,2011,133:11686-11691
18 Liu X,Tang Y,Wang L,et al.Optical detection of mercury(ii)in aqueous solutions by using conjugated polymers and label-free oligonucleotides.Adv Mater,2007,19:1471-1474
19 Liu J W,Lu Y.Adenosine-dependent assembly of aptazyme-functionalized gold nanoparticles and its application as a colorimetric biosensor.Anal Chem,2004,76:1627-1632
20 Liu J,Lu Y.Improving fluorescent dnazyme biosensors by combining inter-and intramolecular quenchers.Anal Chem,2003,75:6666-6672
21 Zhang X B,Wang Z,Xing H,et al.Catalytic and molecular beacons for amplified detection of metal ions and organic molecules with high sensitivity.Anal Chem,2010,82:5005-5011
22 Li H,Zhang Q,Cai Y,et al.Single-stranded dnazyme-based Pb2+fluorescent sensor that can work well over a wide temperature range.Bios Bioelectr,2012,34:159-164
23 Xu W T,Tian J J,Luo Y B,et al.A rapid and visual turn-off sensor for detecting copper(II)ion based on DNAzyme coupled with HCR-based HRP concatemers.Sci Rep,2017,7:43362
24 Liu J,Lu Y.A dnazyme catalytic beacon sensor for paramagnetic Cu2+ions in aqueous solution with high sensitivity and selectivity.JAm Chem Soc,2007,129:9838-9839
25 Li H,Huang X X,Kong D M,et al.Ultrasensitive,high temperature and ionic strength variation-tolerant Cu2+fluorescent sensor based on reconstructed Cu2+-dependent dnazyme/substrate complex.Biosens Bioelectron,2013,42:225-228
26 Cui L,Peng R,Fu T,et al.Biostable l-DNAzyme for sensing of metal ions in biological systems.Anal Chem,2016,88:1850-1855
27 Liu J W,Lu Y.A colorimetric lead biosensor using DNAzyme-directed assembly of gold nanoparticles.J Am Chem Soc,2003,125:6642-6643
28 Mei S H J,Liu Z J,Brennan J D,et al.An efficient RNA-cleaving DNA enzyme that synchronizes catalysis with fluorescence signaling.J Am Chem Soc,2003,125:412-420
29 Kandadai S A,Li Y.Characterization of a catalytically efficient acidic RNA-cleaving deoxyribozyme.Nucleic Acids Res,2005,33:7164-7175
30 Ali M M,Kandadai S A,Li Y.Characterization of ph3dz1-An RNA-cleaving deoxyribozyme with optimal activity at pH 3.Can JChem,2007,85:261-273
31 Aguirre S D,Ali M M,Kanda P,et al.Detection of bacteria using fluorogenic dnazymes.J Vis Exp,2012,3961
32 Ali M M,Aguirre S D,Lazim H,et al.Fluorogenic dnazyme probes as bacterial indicators.Angew Chem,2011,50:3751-3754
33 Zhang W,Feng Q,Chang D,et al.In vitro selection of RNA-cleaving dnazymes for bacterial detection.Methods,2016,106:66-75
34 Yousefi H,Ali M M,Su H M,et al.Sentinel wraps:Real-time monitoring of food contamination by printing dnazyme probes on food packaging.ACS Nano,2018,12:3287-3294
35 He S,Qu L,Shen Z,et al.Highly specific recognition of breast tumors by an RNA-cleaving fluorogenic dnazyme probe.Anal Chem,2015,87:569-577
36 Shahsavar K,Hosseini M,Shokri E,et al.A sensitive colorimetric aptasensor with a triple-helix molecular switch based on peroxidase-like activity of a dnazyme for ATP detection.Anal Methods,2017,9:4726-4731
37 Xu J,Wei C.The aptamer DNA-templated fluorescence silver nanoclusters:ATP detection and preliminary mechanism investigation.Biosens Bioelectron,2017,87:422-427
38 Lu L,Si J C,Gao Z F,et al.Highly selective and sensitive electrochemical biosensor for atp based on the dual strategy integrating the cofactor-dependent enzymatic ligation reaction with self-cleaving DNAzyme-amplified electrochemical detection.Biosens Bioelectron,2015,63:14-20
39 Kong R M,Zhang X B,Chen Z,et al.Unimolecular catalytic DNA biosensor for amplified detection of l-histidine via an enzymatic recycling cleavage strategy.Anal Chem,2011,83:7603-7607
40 He J L,Wu P,Zhu S L,et al.Cleaved dnazyme substrate induced enzymatic cascade for the exponential amplified analysis of l-histidine.Talanta,2015,132:809-813
41 Jiao X X,Nian H Q,Li B.Fabrication of graphene-gold nanocomposites by electrochemical co-reduction.J Electroanal Chem,2013,691:83-89
42 Baum D A,Silverman S K.Deoxyribozymes:Useful DNA catalysts in vitro and in vivo.Cellular Mol Life Sci,2008,65:2156-2174
43 Dass C R,Choong P F,Khachigian L M.DNAzyme technology and cancer therapy:Cleave and let die.Mol Cancer Ther,2008,7:243-251
44 Cairns M J,Hopkins T M,Witherington C,et al.The influence of arm length asymmetry and base substitution on the activity of the10-23 DNA enzyme.Antis Nucl A,2000,10:323-332
45 Wu Y,Yu L,McMahon R,et al.Inhibition of BCR-ABL oncogene expression by novel deoxyribozymes(DNAzymes).Hum Gene Ther,1999,10:2847-2857
46 Fan H,Zhang X,Lu Y.Recent advances in DNAzyme-based gene silencing.Sci China Chem,2017,60:591-601
47 Fan H,Zhao Z,Yan G,et al.A smart DNAzyme-MnO2 nanosystem for efficient gene silencing.Angew Chem,2015,54:4801-4805
48 Santoro S W,Joyce G F.A general purpose RNA-cleaving DNA enzyme.Proc Natl Acad Sci USA,1997,94:4262-4266
49 Unwalla H,Banerjea A C.Novel mono-and di-DNA-enzymes targeted to cleave TAT or TAT-REV RNA inhibit HIV-1 gene expression.Antiviral Res,2001,51:127-139
50 Unwalla H,Banerjea A.Inhibition of HIV-1 gene expression by novel macrophage-tropic DNA enzymes targeted to cleave HIV-1TAT/rev RNA.Biochem J,2001,357:147-155
51 Jing M X,Hong Y,Rao Y F,et al.Inhibition on hepatitis b virus e-gene expression of 10-23 DNAzyme delivered by.Carbohyd Polym,2012,87:1342-1347
52 Schubert S.Rna cleaving“10-23”DNAzymes with enhanced stability and activity.Nucl Acids Res,2003,31:5982-5992