54 results about "Nucleic acid structure" patented technology

The present application relates to the technical field of nucleic acid detection, in particular to a RNA pathogen chemiluminescence detection method based on nucleic acid structure and sequence characteristics. The present application provides a pathogen RNA rapid detection technology based on the reporter molecule cyclization combined with rolling circle amplification according to the secondary structure and sequence characteristics of RNA, which is suitable for high-sensitivity and high-specificity detection of RNA pathogens such as respiratory viruses. The present application innovatively combines the target structure characteristics with sequence specificity, breaks through the traditional sequence-dependent isothermal amplification technology, realizes the highly specific reporter molecule cyclization, significantly improves the detection reliability, and does not require complex instruments. After the swab sample is collected, the pathogen RNA is rapidly released by using a nucleic acid releasing agent, without complex purification steps, and the reading can be realized through a common chemiluminescence instrument, which is suitable for primary site detection.

The invention discloses a cell membrane in-situ drug membrane protein target screening method based on variable configuration DNA, and belongs to the technical field of biological medicine. Two pairs of functionalized nucleic acid structures are constructed, the first pair is S1S2 semi-complementary DNA double strands, the second pair is S3S4 DNA-RNA hybrid double strands, and the S1S2 structure is covalently coupled to a non-natural amino acid site-directed modified membrane protein through a click chemical reaction in a living cell to realize tagging of the membrane protein; when the candidate drug coupled in S3 interacts with the membrane protein, triggering an allosteric response system to release the tagged chain in S1; the released DNA tag is subjected to PCR amplification and sequencing, and accurate identification and analysis of a membrane protein target are realized according to a tag sequence. The invention provides a high-specificity and non-in-vitro drug membrane protein target screening technology. According to the technology, active compound discovery or accurate screening of drug membrane protein targets in a living cell in-situ environment can be realized.

The invention relates to the technical field of nucleic acid detection, in particular to an RNA pathogen chemiluminescence detection method based on a nucleic acid structure and sequence characteristics. The invention provides a pathogen RNA rapid detection technology which is based on RNA secondary structure and sequence characteristic reporter molecule cyclization and is combined with rolling circle amplification, and is suitable for high-sensitivity and high-specificity detection of RNA pathogens such as respiratory viruses. Target structure characteristics and sequence specificity are creatively combined, a traditional sequence-dependent isothermal amplification technology is broken through, high-specificity reporter molecule cyclization is achieved, the detection reliability is remarkably improved, complex instruments are not needed, after swab samples are collected, pathogen RNA is rapidly released through a nucleic acid releasing agent, complex purification steps are not needed, and the method is suitable for large-scale popularization and application. And reading can be realized through a common chemiluminiscence instrument, and the method is suitable for base-level field detection.

The invention belongs to the technical field of biology, and particularly relates to regulation and control of cinnamyl aldehyde on hyperuricemia related gene promoter region G quadruplex. According to the application disclosed by the invention, firstly, the capacity of cinnamyl aldehyde for regulating and controlling a G quadruplex in a hyperuricemia related gene promoter region is explored by utilizing circular dichroism, and the influence of cinnamyl aldehyde on regulation and control of a nucleic acid structure is further evaluated by utilizing a fluorospectro photometer, so that support is provided for a molecular mechanism of cinnamyl aldehyde for relieving hyperuricemia on a gene level. In conclusion, the invention discloses a brand new mechanism that cinnamyl aldehyde regulates and controls uric acid metabolism related genes through a targeted G quadruplex structure, a precise action target and a potential drug development direction are provided for treatment of hyperuricemia, and meanwhile, an established small molecule and G quadruplex interaction verification method provides technical reference for similar research.

A nucleic acid structural analysis method includes: an HAD-MSn analysis step (101) of introducing a hydrogen radical into a space in which an ion derived from a test nucleic acid is present to perform dissociation of the ion, and performing mass spectrometry on a plurality of fragment ions generated by the dissociation to collect m / z information on the plurality of fragment ions; and a structure estimation step (103) of estimating a structure of the test nucleic acid on a basis of the m / z information on the plurality of fragment ions obtained in the HAD-MSn analysis step. This makes it possible to deal with precursor ions having various charges, and makes it easier to perform the structure estimation of the nucleic acid based on the mass spectrum.

A nucleic acid construct encoding multiple polypeptide antigens or immunogens, or other polypeptides of interest. The construct expresses a protein that includes immunogenic or antigenic sequences from two, three, or more polypeptides of interest. Once expressed by the nucleic acid construct, the protein is processed by cleavage of an N-terminal signal peptide and by cleavage of 6K, 6K-like, or internal signal peptide cleavage sites to release each polypeptide of interest.

The application discloses a method for constructing a high-throughput protein capture interface by antibody adsorption, which comprises the following steps: S1, synthesizing a tetrahedral framework nucleic acid structure; S2, mixing a capture antibody and the synthesized tetrahedral framework nucleic acid structure on a gold island substrate to prepare a high-throughput protein capture interface; S3, placing the gold island substrate in a wet box for overnight incubation; S4, blocking the capture interface to prevent non-specific adsorption; S5, incubating a protein target; S6, incubating a detection antibody; S7, incubating a fluorescent secondary antibody; S8, washing the capture interface with pure water and centrifuging and air-drying; and S9, performing fluorescent imaging and quantification on the capture interface by using a chip scanner. The method for constructing a high-throughput protein capture interface by antibody adsorption has high uniformity, and can realize high-throughput, high-sensitivity and high-accuracy protein capture and quantitative detection.

Disclosed herein are methods and compositions for enhancing delivery and function of vaccine components, immunotherapy Agents, and improved delivery of nucleic acid nanostructures, nucleic acids, peptides, polypeptides, and other types of cargoes. These methods and compositions utilize design components suitable for rapid and cost-effective manufacturing, and are designed to exclusively use the process of self-assembly to form nanotherapeutics requiring no purification in many instances.

The present invention relates to a novel gene therapeutic agent capable of inhibiting FABP4 and / or FABP5, and relates to a nucleic acid construct capable of inhibiting target gene(s), FABP4 and / or FABP5, and use thereof for treating obesity or obesity-derived metabolic diseases. The nucleic acid construct according to the present invention effectively inhibits the expression of FABP4 and / or FABP5 by targeting adipocytes, thereby achieving the effects of reducing body weight, reducing inflammatory cytokines in adipose tissue, reducing lipids, and ameliorating insulin resistance and glucose tolerance, and thus can be used in the development of therapeutic agents for obesity or obesity-derived metabolic diseases.

The invention relates to a nucleic acid detection system based on glass nanopores and nanomanipulation as well as a preparation method and application of the nucleic acid detection system, and belongs to the technical field of biology. Aiming at the technical problems of difficulty in signal capture, incapability of realizing accurate space positioning and insufficient complex structure detection accuracy caused by too high nucleic acid translocation speed in the existing nanopore technology, a DNA chip is combined with a nanomanipulation technology. A modified glass chip of which the surface is fixed with double Gap double-stranded DNA is constructed, a glass nanopore is matched, an electric field is applied by utilizing a patch clamp system, and a piezoelectric ceramic nano displacement platform is combined to realize accurate control on a DNA structure. According to the method, fixed-point capture, multiple repeated detection and accurate distinguishing of sequences with different lengths of nucleic acid are realized, the detection limitation of a traditional nanopore technology on a complex nucleic acid structure is solved, and the method has important application value in the fields of gene diagnosis and nanopore sequencing.

The present disclosure in some aspects relates to methods and compositions for accurately detecting and quantifying multiple analytes present in a biological sample. In some aspects, the methods and compositions provided herein address one or more issues associated with the stability and / or size of nucleic acid structures such as rolling circle amplification products in the biological sample.

A method for nucleic acid detection based on a ternary DNA coding library belongs to the technical field of in vitro nucleic acid detection. The method aims to quickly determine whether a specific gene fragment is present in a solution through the coding library. By setting a certain number of nucleic acid structures in the coding region on the carrier, the size and number of nucleic acid structures in different locations determine the intensity of the nanopore electrical signal, thereby forming a multi-level electrical signal, and then creating a multi-binary coding library. Probes and marker nucleic acid structures are set in the sensing area of ​​the carrier to detect specific gene fragments. This method is based on DNA data coding structure for library construction and is an emerging rapid detection method with the characteristics of high sensitivity and high throughput.

An object is to provide a technique for detecting a test substance more easily using a nucleic acid structure. The object is achieved by a nucleic acid structure comprising a partial nucleic acid structure 1 and a partial nucleic acid structure 2, the partial nucleic acid structure 1 and the partial nucleic acid structure 2 being linked by a Holliday junction, the partial nucleic acid structure 1 comprising a protruding structure 1a containing a nucleic acid aptamer sequence, and a protruding structure 1b containing a split domain 1 of an enzyme, and the partial nucleic acid structure 2 comprising a protruding structure 2a containing a sequence complementary to part or all of the nucleic acid aptamer sequence, and a protruding structure 2b containing a split domain 2 paired with the split domain 1.

The present disclosure in some aspects relates to methods and compositions for accurately detecting and quantifying multiple analytes present in a biological sample. In some aspects, the methods and compositions provided herein address one or more issues associated with the stability and / or size of nucleic acid structures, such as RCPs, in the biological sample without the use of exogenously added oligonucleotide compaction probes. In some embodiments, provided herein are methods involving the use of self-hybridizing hybridizing regions for compacting and / or stabilizing nucleic acid concatemers (e.g., RCPs). In some embodiments, dynamic inter-strand annealing between tandem units of an RCP is used for compaction and / or stabilization. In some embodiments, short palindromic regions in an RCP are used for compaction and / or stabilization.

This invention provides constructs and methods for modulating the relative expression of transgenes. [Solution] In a first aspect, the present invention provides a nucleic acid construct comprising a first-objective nucleotide sequence (NOI1); a flame slip motif or translational read-through motif (FSM / TRM); and a second-objective nucleotide sequence (NOI2). The nucleic acid construct may also include nucleotide sequences encoding cleavage sites (CLs) such that NOI1 and NOI2 are expressed as distinct proteins.

The present disclosure in some aspects relates to methods and compositions for accurately detecting and quantifying multiple analytes present in a biological sample. In some aspects, the methods and compositions provided herein address one or more issues associated with the stability and / or size of nucleic acid structures such as rolling circle amplification products in the biological sample.

Fluorescent nucleobase surrogates capable of Watson-Crick hydrogen bonding are essential probes of nucleic acid structure and dynamics. Their limited brightness and short absorption and emission wavelengths have rendered them unsuitable for single-molecule detection. Herein, we synthesized a new tricyclic pyrimidine nucleoside analogue with a push-pull conjugated system. The resulting C-linked 8-(diethylamino)benzo[b][1,8] naphthyridin-2(1H)-one nucleoside (ABN), exhibits ε442=20,000 M−1 cm−1 and Φem,540=0.39 in water, increasing to Φem=0.50-0.53 when base paired with adenine in duplex DNA oligonucleotides. Single-molecule fluorescence measurements of ABN using both one-photon and two-photon excitation demonstrate its excellent photostability and indicate that the nucleoside is present to >95% in a bright state with count rates of at least 15 kHz per molecule. This new fluorescent nucleobase analogue, which, in duplex DNA, is the brightest and most red-shifted known, is first to offer robust single-molecule fluorescence detection capabilities.

The present disclosure in some aspects relates to methods and compositions for accurately detecting and quantifying multiple analytes present in a biological sample. In some aspects, the methods and compositions provided herein address one or more issues associated with the stability and / or size of nucleic acid structures, such as RCPs, in the biological sample without the use of exogenously added oligonucleotide compaction probes. In some embodiments, provided herein are methods involving the use of self-hybridizing hybridizing regions for compacting and / or stabilizing nucleic acid concatemers (e.g., RCPs). In some embodiments, dynamic inter-strand annealing between tandem units of an RCP is used for compaction and / or stabilization. In some embodiments, short palindromic regions in an RCP are used for compaction and / or stabilization.

To provide: methods of proximity ligation and compositions for use in such methods; and embodiments related to single cell nucleic acid conformation assessment or to single cell nucleic acid sequence or phase information determination.SOLUTION: Conformation-preserved or conformation-reconstructed nucleic acid samples can be fragmented and distributed in aliquots to which aliquot-distinguishing sequence segments can be added so that, upon analysis of a paired end library generated from the samples, paired ends can be assigned to a partition, or cell, of origin. Thus cell-specific variation in sequence and / or three-dimensional nucleic acid configuration can be determined.SELECTED DRAWING: Figure 25

The application discloses a tetrahedral framework nucleic acid complex loaded with equol and application of the complex in preparation of a medicine for relieving fatty liver disease. The complex is obtained by stable combination of tetrahedral framework nucleic acid and equol through hydrogen bond and hydrophobic interaction; the equol is loaded on the tetrahedral framework nucleic acid structure, and can be slowly released, so that the bioavailability of the equol is improved, and the problems of poor water solubility and low stability of the equol are effectively overcome. Meanwhile, the complex can inhibit lipid accumulation in HepG2 cells, relieve lipid deposition of liver cells, and reduce accumulation of TG and T-CHO in cells, and can be used for relieving fatty liver, and preparing more and more efficient fatty liver treatment medicines, and has wide application potential in intervention of lipid metabolism disorder and related metabolic diseases.

The present invention is directed to a nanoscaled construct, said construct comprising or essentially consisting of a nucleic acid structure with reconfigurable or switchable features, and at least two separate metallic nanoparticles coupled with said nucleic acid structure, wherein said two separate nanoparticles are at an interchangeable angle to each other, wherein said nanoparticles provide high chirality and / or optical activity within the visible and near-infrared (NIR) spectrum from 400 to 800 nm generating a color for the construct, and wherein said construct has an absorption dissymmetry factor (g-factor) of over 10%. There is also provided a method for detecting an analyte in a sample, the method comprising steps of contacting a nanoscaled construct of the present disclosure specific to said analyte with a sample in a test assay, and detecting said analyte in said sample by optical means or by naked eye, wherein the presence of the analyte in said sample changes the color of said nanoscaled structure and the change of color in said assay confirms the presence of the analyte in said sample.

The invention discloses a bionic black phosphorus nano material as well as preparation and application thereof. The preparation method comprises the following steps: S1, preparing black phosphorus nanosheets; s2, preparing a carboxylated black phosphorus nanosheet; s3, preparing a composite black phosphorus nano material; and S4, preparing the bionic black phosphorus nano material. The structure core of the bionic black phosphorus nanomaterial is composed of black phosphorus nanosheets, and after the black phosphorus nanosheets are modified by double-terminal carboxyl polyethylene glycol, the black phosphorus nanosheets can be covalently linked with an amino-modified Anti miR 33 nucleic acid inhibitor through terminal carboxyl of the black phosphorus nanosheets, so that the aims of protecting the nucleic acid structure and improving the delivery efficiency are fulfilled; and then coating the material by adopting a cell membrane derived from M2c phenotype macrophages, so as to endow the material with an active targeting capability in an inflammatory region.

Fluorescent nucleobase surrogates capable of Watson-Crick hydrogen bonding are essential probes of nucleic acid structure and dynamics. Their limited brightness and short absorption and emission wavelengths have rendered them unsuitable for single-molecule detection. Herein, we synthesized a new tricyclic pyrimidine nucleoside analogue with a push-pull conjugated system. The resulting C-linked 8-(diethylamino)benzo[b][1,8] naphthyridin-2(1H)-one nucleoside (ABN), exhibits ε442=20,000 M−1 cm−1 and Φem,540=0.39 in water, increasing to Φem=0.50-0.53 when base paired with adenine in duplex DNA oligonucleotides. Single-molecule fluorescence measurements of ABN using both one-photon and two-photon excitation demonstrate its excellent photostability and indicate that the nucleoside is present to >95% in a bright state with count rates of at least 15 kHz per molecule. This new fluorescent nucleobase analogue, which, in duplex DNA, is the brightest and most red-shifted known, is first to offer robust single-molecule fluorescence detection capabilities.

The nucleic acid structure according to the present invention can increase capture efficiency in a drug delivery system by allowing a hydrophobic moiety to be introduced through hybridization of a desired nucleic acid molecule with another nucleic acid molecule that contains the hydrophobic moiety and a sequence complementary to an arbitrary sequence present in the desired nucleic acid molecule, thereby enabling in vivo delivery efficiency, stability and expression efficiency to be improved, and thus can be effectively used as an improved drug delivery system and biopharmaceutical.

The invention relates to a method for recognizing a G-quadruplex (G4) in a cell by utilizing a G4 fluorescent probe 2-(2-hydroxy-6-methoxy-3-propionyl phenyl) quinazoline-4 (3H)-ketone (HMPQ). The method comprises the following steps: firstly, adding a fluorescent probe 2-(2-hydroxy-6-methoxy-3-propionyl phenyl) quinazoline-4 (3H)-ketone (HMPQ) into a cell; the probe has specific binding affinity to G-quadruplex, and can illuminate the non-standard nucleic acid structures without changing the conformation of the probe. G4 participates in chromatin tissue, gene regulation, and genomic stability, and appears to contribute to the growth and progression of cancer. By utilizing the unique fluorescence mechanism of HMPQ (i.e., excited state intramolecular proton transfer), the method can achieve label-free accurate detection of the G4 structure in the cell nucleus. The invention also relates to an unmarked kit for selectively detecting the G-quadruplex (G4) in the cell.

The invention provides a game assembly system for nucleic acid structure and genetic information transfer teaching. The assembly system adopts entity cards which can be independently operated and combined, and is divided into at least five levels according to a nucleic acid structure composition relationship: a nucleic acid whole body, DNA / RNA or a nucleotide set, a nucleotide category, and specific nucleotides and basic structure units (basic groups, pentose and phosphoric acid). Each basic unit is provided with a connecting structure, each nucleotide card is provided with a receiving structure, the connecting structures and the receiving structures are differentially coded according to a composition relation, and corresponding nucleotides can be formed by stable connection only when the types and the number of the selected basic units are matched; and physical mistake proofing is realized, and the teaching intuition and accuracy are improved by displaying the hierarchical composition of nucleic acid through the corresponding inclusion of the high-level and low-level components.

The invention relates to the technical field of medicines, in particular to a linear nucleic acid structure with a cGAS-STING excitation function and application of the linear nucleic acid structure. According to the invention, a stable DNA nanostructure is designed and synthesized, and is modified by the aptamer, so that the targeting and stability of nucleic acid are improved, and the requirement of activating a cGAS-STING pathway is met. The composite material has good biocompatibility, and can effectively activate an immune system and enhance immune recognition and killing effects on tumor cells. In vitro and mouse tumor models, the prepared nano-carrier can activate the STING pathway, can also significantly improve the tumor immunotherapy effect, and has good preclinical application prospects in the aspects of prolonging the tumor lifetime and slowing down tumor progression. The invention provides a new strategy and technical support for tumor immunotherapy, can be used as a carrier to effectively transfer drugs, and has wide application value.

The application discloses a kind of bionic black phosphorus nanomaterial and its preparation and application, including the following steps: S1, the preparation of black phosphorus nanosheet;S2, the preparation of carboxylated black phosphorus nanosheet;S3, the preparation of composite black phosphorus nanomaterial;S4, the preparation of bionic black phosphorus nanomaterial.The structural core of the bionic black phosphorus nanomaterial is composed of black phosphorus nanosheet, which can be covalently connected to the amino-modified Anti miR 33 nucleic acid inhibitor through its terminal carboxyl group after modification by double-end carboxyl polyethylene glycol, to achieve the purpose of protecting nucleic acid structure and improving delivery efficiency, and then the material is coated with cell membrane derived from M2c phenotype macrophages, thereby endowing the material with active targeting ability in inflammatory areas.