121 results about "Modified dna" patented technology

The invention discloses a nano magnetic bead for specific capture of DNA (deoxyribonucleic acid) of bacteria and fungi, a preparation method of the nano magnetic bead and a rapid sterile detection method of a cell therapy product. The method comprises the following steps: S1, coating Fe3O4 with polydopamine to form a modified Fe3O4 magnetic bead; s2, compounding the MOF shell layer to the modified Fe3O4 magnetic beads to form Fe3O4-coated MOF magnetic beads; s3, gold nanoparticles are anchored to the Fe3O4 (at) MOF magnetic beads to form Fe3O4 (at) MOF (at) Au magnetic beads; and S4, modifying the Fe3O4 (at) MOF (at) Au magnetic bead with a specific capture probe aiming at DNA of bacteria and fungi to form a Fe3O4 (at) MOF (at) Au-Probe probe magnetic bead. The modified DNA probe disclosed by the invention can efficiently capture free bacteria and fungus nucleic acid fragments in a sample, so that template enrichment is realized.

Provided herein are epigenetic-modifying DNA-targeting systems, such as CRISPR-Cas / guide RNA (gRNA) systems, for the transcriptional repression of Hepatitis B viral (HBV) genes to promote a cellular phenotype that leads to the reduction of HBV infection. In some embodiments, the epigenetic-modifying DNA-targeting systems bind to or target a target site of at least one gene or regulatory element thereof in a Hepatitis B viral DNA sequence in cell. In some aspects, the provided systems relate to the transcriptional repression of one or more Hepatitis B viral gene and / or regulatory element thereof. In some aspects, also provided herein are methods and uses related to the provided compositions, for example in repressing Hepatitis B viral replication and expression in connection with Hepatitis B infections.

The invention relates to the field of DNA nanotechnology, and discloses a DNA origami structure based on functionalized magnetic nanoparticles, a preparation method and application, and the preparation method comprises the following steps: step 1, constructing a DNA origami structure with a cavity through a self-assembly method; the short chains in the DNA origami structure comprise a first short chain, a second short chain and a third short chain; 2, connecting a sulfydryl-functionalized first sequence to the first short chain, and chelating ferrous ions on the first sequence to obtain a sulfydryl-modified DNA origami structure; 3, ferrous ions chelated on the sulfydryl modified DNA origami structure are reduced, and a magnetic functionalized DNA origami structure internally loaded with Fe2O3 particles is obtained; and 4, connecting an antibody to a second short chain in the DNA origami structure through base complementary pairing to obtain the required DNA origami structure. According to the invention, DNA origami is combined with magnetic nanoparticles, efficient and controllable biological magnetic beads are obtained through dual immobilization and antibody modification, and a traditional application scene of DNA origami is broken through.

The disclosure provides, for example, DNA molecules comprising at least one nucleotide with a macromolecule, small molecule, or reactive handle (e.g., click handle) appended to a phosphorothioate backbone. The disclosure also provides methods for making such DNA molecules, for example using click chemistry. In some embodiments, the DNA molecule comprises a sequence that encodes an effector (e.g., a therapeutic effector).

Provided in some aspects are epigenetic-modifying DNA-targeting systems, such as CRISPR-Cas / guide RNA systems, that bind to or target a target site in a gene or regulatory element thereof in a T cell. In some aspects, the provided epigenetic modifying DNA-targeting systems provided herein modulate a T cell phenotype or activity. In particular, the provided embodiments relate to the transcriptional repression of genes to promote a stem cell-like memory T (TSCM) cell phenotype. In some aspects, also provided are compositions, polynucleotides, vectors, cells, and pluralities and combinations thereof, and methods and uses related to the provided epigenetic-modifying DNA-targeting systems, for example in modulating the phenotype in T cells including in connection with adoptive T cell therapy.

Provided herein are epigenetic-modifying DNA-targeting systems, such as CRISPR-Cas / guide RNA (gRNA) systems, that bind to or target multiple genes or regulatory elements thereof, for instance in a T cell. In some aspects, the provided epigenetic-modifying DNA-targeting systems promote increased transcription of one or more first genes and promote repressed transcription of one or more second genes. In some aspects, the provided epigenetic-modifying DNA-targeting systems modulate a T cell function, such as a T cell phenotype or activity. Also provided herein are polynucleotides, vectors, cells, methods, and uses related to the provided epigenetic-modifying DNA-targeting systems, for example in modulating T cells, such as in connection with methods of adoptive T cell therapy.

The invention discloses a nuclear targeting peptide modified DNA nano-particle based on a microfluidic technology and a preparation method and application thereof, and relates to the technical field of biological medicine, a poly (beta-amino ester) cationic polymer is used as a gene delivery carrier, the gene delivery carrier comprises a microtubule related sequence MTAS and a nuclear localization signal NLS oligopeptide, the gene delivery carrier and the plasmid DNA carrying the target gene are mixed to prepare nano-particles, and the plasmid DNA carrying the target gene is uniformly dispersed in the nano-particles by adopting a microfluidic mixing process; the nuclear targeting peptide modified DNA nano-particle is ingenious in structural design, the mixing uniformity of a nano-carrier and plasmid DNA is improved by adopting a micro-fluidic mixing process, the performance of the nano-particle is further improved by optimizing dialysis conditions, potential cytotoxicity and adverse effects are reduced, and the nuclear targeting peptide modified DNA nano-particle is suitable for large-scale production. And after transduction of non-activated T cells, strong tumor killing ability and cytokine secretion can be generated.

We describe compositions of DNA donor molecules compatible with various gene insertion methods with major advantages for delivery, nuclear localization, and immune evasion. The modified DNA donor molecules are largely single stranded but contain short regions of double-strand DNA to reconstitute enzyme binding sites, and can be combined with other approaches to enhance donor recruitment into the nucleus.

The invention provides a DNA tetrahedral nano device with cholesterol molecule space accurate arrangement and a preparation method and application thereof. Specifically, the invention provides a nucleic acid tetrahedral nanostructure which comprises a tetrahedral composite structure formed by assembling a plurality of nucleic acid monomers, and the tetrahedral composite structure is coupled with cholesterol molecules. According to the invention, the addressability and programmability of the DNA nanotechnology are utilized, and the spatial position of cholesterol molecules in the DNA nanostructure can be accurately controlled, so that the advantages of greatly improving the biological stability, improving the pharmacokinetic and pharmacodynamic properties, enhancing the stability, improving the in-vivo distribution of drugs and the like can be achieved.

The invention provides a retrotransposase, which comprises a target DNA binding structural domain containing a zinc finger binding motif, a reverse transcriptase structural domain and an endonuclease structural domain, and can be used for reversely transcribing RNA (Ribonucleic Acid) into DNA. The amino acid sequence of the retrotransposase is shown as any one of SEQ ID No.1 to 6 or SEQ ID No.32 to 43 or SEQ ID No.68 to 71 or has at least 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98% and 99% identity with the amino acid sequence of any one of SEQ ID No.1 to 6 or SEQ ID No.32 to 43 or SEQ ID No.68 to 71. The invention also relates to a system for modifying DNA. The system comprises the retrotransposase provided by the invention or a nucleic acid encoding the retrotransposase provided by the invention; and a donor RNA or a nucleic acid encoding the donor RNA, the donor RNA comprising: a sequence that binds to the retrotransposase and a heterologous sequence.

To provide technology for pancreatic ductal adenocarcinoma (PDAC) screening and particularly, but not exclusively, methods, compositions, and related uses for detecting the presence of PDAC.SOLUTION: A method is provided, comprising: treating genomic DNA in a biological sample with a reagent that modifies DNA in a methylation-specific manner; amplifying the treated genomic DNA using a set of primers for one or more selected genes; and determining the methylation level of the one or more genes by polymerase chain reaction, nucleic acid sequencing, mass spectrometry, methylation-specific nuclease, mass-based separation, and target capture, thereby measuring the methylation level of the one or more genes in the biological sample of the human individual.SELECTED DRAWING: Figure 2

The present invention relates generally to compositions, systems and methods for modulating hepatitis B virus (HBV) by targeting gene repression. In particular, the present invention provides an epigenetically modified DNA targeting system, such as a CRISPR-Cas / guide RNA (gRNA) system, for transcriptional repression of hepatitis B virus genes to promote cell phenotypes that lead to reduced HBV infection. In some embodiments, the epigenetically modified DNA targeting systems of the present invention bind to or target a target site of at least one gene in the hepatitis B virus DNA sequence or a regulatory element thereof in a cell. In some aspects, the systems provided herein relate to transcriptional repression of one or more hepatitis B virus genes and / or regulatory elements thereof. In some aspects, the invention also provides methods and uses associated with the provided compositions, such as in repression of hepatitis B virus replication and expression associated with hepatitis B infection.

Disclosed are compositions, methods, and kits for modifying DNA within cells as well as compositions and methods for modifying gene expression in a cell. In particular, the invention generally relates to compositions, methods, and kits for DNA editing using single-stranded DNA. Compositions and methods for modifying gene expression using artificial microRNAs (amiRNA) are also contemplated.

Provided is a means for constructing a modified genomic DNA which has a nucleotide sequence different from an existing genomic DNA sequence, contains a modified gene capable of expressing a polypeptide, a functional RNA, or both, and does not contain exogenous DNA.　This method comprises: performing, at least twice, (a) a step for specifically cleaving genomic DNA of a cell into at least two target sequences by means of a sequence-specific nuclease, and linking the resultants through a DNA double-stranded cleavage repair by the cell; and deleting at least two regions from an existing gene and non-coding regions adjacent thereto to thereby produce a modified gene.

The invention provides a preparation method and application of a directional degradation liquid, and the preparation method comprises the following steps: adopting natural protein as a carrier, reducing by a reducing agent, and carrying out Michael addition reaction on the reduced natural protein, coupling agent modified DNA enzyme and chloroquine to obtain the directional degradation liquid, compared with the prior art, natural cationic glycoprotein lactoferrin is adopted as a carrier, surface charges of the lactoferrin are mostly distributed as positive charges under physiological conditions, and the lactoferrin can be rapidly and directionally enriched to a bacterial biofilm carrying a large number of negative charges through electrostatic interaction; under the action of a Michael addition reaction, lactoferrin, DNA enzyme and chloroquine are prepared into a directional degradation solution, a nucleic acid intercalator chloroquine is utilized to maintain eDNA configuration in a biological membrane to be a B type, and based on the enzymatic hydrolysis capacity of the DNA enzyme, the bacterial biological membrane is efficiently disintegrated, and the bacterial drug sensitivity is improved.

The invention provides an FSH33 peptide modified DNA tetrahedron nano delivery system as well as a preparation method and application thereof, and aims to provide a safe and efficient antioxidant nano drug and optimize the enrichment efficiency to promote ovarian aging and ovarian tissue damage repair. The system is a nano-scale nucleic acid compound composed of a tetrahedral DNA frame structure and an FSH targeting peptide. The tetrahedral DNA frame structure is a microscopic 3D stereoscopic tetrahedral structure formed by self-assembly of DNA single chains of a specific nucleic acid sequence, wherein each side extends out of a viscous end used for being connected with an FSH peptide. The research finds that the DNA tetrahedron can safely and effectively improve the ovarian endocrine function, ovarian reserve, fertility and the like of mice in a drug protection group, has no obvious toxic or side effect on all organs and tissues of the whole body, and can promote the repair of ovarian oxidative damage.

The invention provides a short polyarginine modified DNA probe as well as a preparation method and application thereof, and belongs to the technical field of biological analysis and detection. The preparation method of the short polyarginine modified DNA probe comprises the following steps: dissolving base-deficient site DNA in a buffer solution, and adding a coupling molecule linker for reaction to obtain an intermediate; and adding the purified intermediate into an Arg5-PEG1000-azide solution, and carrying out a click chemical reaction, so as to obtain the short polyarginine modified DNA probe. The invention also provides the short polyarginine modified DNA probe and application thereof. The short polyarginine modified DNA probe can generate characteristic and recognizable current signals through the nanopores so as to realize enzyme and small molecule detection, and has the advantages of high signal frequency, strong specificity, simple synthesis and great application potential.

The invention provides a retrotransposase, which comprises a target DNA binding structural domain containing a zinc finger binding motif, a reverse transcriptase structural domain and an endonuclease structural domain, and can be used for reversely transcribing RNA (Ribonucleic Acid) into DNA. The invention also relates to a system for modifying DNA. The system comprises the retrotransposase provided by the invention or a nucleic acid encoding the retrotransposase provided by the invention; and a donor RNA or a nucleic acid encoding the donor RNA, the donor RNA comprising: a sequence that binds to the retrotransposase and a heterologous sequence.

Epigenetically modified DNA targeting systems, such as CRISPR-Cas / guide RNA (gRNA) systems, are provided that bind to or target one or more target sites in the IL-2 gene or its regulatory elements in cells such as lymphoid cells (e.g., T cells). In some embodiments, the provided epigenetically modified DNA targeting systems modulate the phenotype or activity of lymphoid cells, or the function of lymphoid cells such as the phenotype or activity of T cells. In some embodiments, methods and uses relating to the provided compositions in the modulation of lymphoid cells such as T cells are also provided, for example, in connection with adoptive T cell therapy.

We describe compositions of DNA donor molecules compatible with various gene insertion methods with major advantages for delivery, nuclear localization, and immune evasion. The modified DNA donor molecules are largely single stranded but contain short regions of double-strand DNA to reconstitute enzyme binding sites, and can be combined with other approaches to enhance donor recruitment into the nucleus.

The invention relates to methods of modifying DNA methylation by contacting a cell with a catalytically inactive site specific nuclease fused to an effector domain having methylation or demethylation activity and one or more guide sequences.

This invention relates to DNA-functionalized thermosensitive phase transition polymers, their preparation methods, and applications, belonging to the interdisciplinary field of functional polymers and biomaterials. It aims to solve the technical problems of existing exosome separation methods, such as long processing time, low purity, high cost, and inability to specifically separate exosome subtypes. This invention provides a polymer prepared via free radical polymerization using N-isopropylacrylamide and acrylamide-modified DNA as monomers, and ammonium persulfate and tetramethylethylenediamine as initiators. This polymer exhibits reversible phase transition properties at physiological temperatures and is applied to the separation and detection of exosome subtypes. Specific capture and quantitative analysis are achieved through DNA recognition probes and fluorescently labeled antibodies. The polymer of this invention is simple to operate, quick to prepare, low in cost, and high in purity. It requires only a common centrifuge for non-destructive separation of exosomes and can integrate detection functions, providing technical support for diagnosis and detection.

Disclosed herein are compositions comprising structurally modified DNA encoded antibodies (DMAbs), methods of structurally modifying DMAbs, and methods of using structurally modified DMAbs.

The invention discloses a nano enzyme with catalyst inactivation resistance and a preparation method and application thereof, and the preparation method comprises the following steps: 1) performing functional pretreatment on DNA to obtain functional modified DNA for subsequent DNA coating construction; and 2) connecting a certain size of metal nanoparticles with catalytic activity with the functionalized modified DNA to construct the DNA coating-coated nano enzyme with catalyst inactivation resistance. The DNA coating on the surface of the prepared nano-enzyme can effectively prevent catalyst inactivation caused by particle aggregation in a high-salt environment, meanwhile, the coating has the function of a molecular sieve, can effectively inhibit non-specific adsorption of biomacromolecules such as protein and the like, allows a small-molecule substrate to be in contact with a catalytic interface, and improves the catalytic activity of the nano-enzyme. Therefore, catalytic activity is maintained in complex biological environments such as serum, sensitive detection of molecules is realized, and a solution is provided for precise medical diagnosis.

To provide means for constructing a modified DNA having a nucleotide sequence different from an existing genome DNA sequence, which is a modified genome DNA including a modified gene in which polypeptide, functional RNA or both can be expressed, but not including a foreign DNA.SOLUTION: A method includes (a) performing a step of cleaving a genome DNA of a cell in at least two target sequences more specifically by a sequence-specific nuclease, and connecting them by DNA double-strand break repair by a cell at least twice, deleting at least two regions from an existing gene and its adjacent non-encoded region to create a modified gene.SELECTED DRAWING: Figure 1A

Provided herein are methods for detecting the presence or progression of a disease in a subject as well as a method for determining the efficacy of a therapy for the disease by administering to the subject a probe comprising a phosphorothioated DNA barcode sequence, wherein the DNA barcode sequence comprises about 36 nucleotides to about 72 nucleotides, and wherein the DNA barcode is released when the disease is present in the subject; obtaining a biological sample containing the released DNA barcode from the subject; and amplifying and detecting the DNA barcode in the biological sample.

The present invention is directed to composition comprising modified DNA identifier sequences (MoDIS) comprising (i) a validation code nucleotide sequence (VC), (ii) a randomized index code nucleotide sequence (RIC) and (iii) an annealing site nucleotide sequence (AS) for specifically binding a primer for PCR amplification, wherein (a) AS is attached to an affinity tag or marker and / or affinity tag compound for the identification, enrichment and / or purification of MoDIS-bound nucleotide sequences; and (b) the nucleotide at the 5'-end of the MoDIS comprises a 5'- azido-modified moiety or a 5'-alkynyl-modified moiety.

The invention relates to a double DNA nanosphere probe (DDNS) as well as a preparation method and biosensing application thereof. The DDNS comprises a DNA (deoxyribonucleic acid) nanosphere 1 (DNS-1) and a DNA nanosphere 2 (DNS-2). The DNS-1 and the DNS-2 are respectively formed by self-assembling two cholesterol modified DNA single-stranded probes with hairpin structures, and are respectively used for identifying target miRNA and triggering a non-enzymatic circulating strand displacement amplification (T-SDA) reaction. The DDNS can realize high-sensitivity fluorescence detection on target miRNA and can effectively inhibit non-target miRNA interference, and the interference inhibition rate is close to 100%. Besides, DDNS has excellent nuclease stability, the system can automatically enter living cells without a transfection reagent, high signal-to-noise ratio fluorescence differentiation of cancer cells and healthy cells is realized on the premise of maintaining cell activity, the performance is equivalent to that of a transfection agent dependent system, and the biological safety is remarkably improved. The invention provides a new material and a new method for application of the DNA nanostructure in the fields of molecular diagnosis and precision medical treatment.

The invention relates to the field of biological detection, in particular to a recombinase activity detection method and a kit. According to the method for detecting the strand displacement activity of the recombinase, the strand displacement template is subjected to fluorescence labeling, a quenching group modified DNA strand is displaced by utilizing the strand displacement effect of the recombinase, and the relative activity of the recombinase to be detected is obtained through a linear fitting equation of the fluorescence intensity increasing rate and the activity. The method can be used for detecting strand displacement products through a fluorescence detection means, is non-toxic and harmless, is simple and feasible, and can be used for determining the strand displacement recombination activity of the recombinase within 1 hour. By using the method, quantitative data of strand displacement activity can be obtained, and the strand displacement activity of recombinase can be accurately analyzed.

The present invention relates to the technical field of gene editing, and provides a DNA repair template and a use thereof. On the basis of the exploration of a preference sequence binding mammalian intracellular protein Rad51 to DNA, a specific nucleic acid binding preference sequence is obtained, and the specific nucleic acid binding preference sequence is added to the 5' end of a conventional DNA repair template, so that the efficiency of DNA repair template mediated accurate gene editing is greatly improved. Also provided are a composition comprising a modified DNA repair template and an inhibitor of an NHEJ pathway such as M3814 and a use of the composition. The composition has higher accurate gene editing efficiency.