41 results about "Dna breakage" patented technology

Factors affecting the fragmentation pattern of cell-free DNA (e.g., plasma DNA) and the applications, including those in molecular diagnostics, of the analysis of cell-free DNA fragmentation patterns are described. Various applications can use a property of a fragmentation pattern to determine a proportional contribution of a particular tissue type, to determine a genotype of a particular tissue type (e.g., fetal tissue in a maternal sample or tumor tissue in a sample from a cancer patient), and/or to identify preferred ending positions for a particular tissue type, which may then be used to determine a proportional contribution of a particular tissue type.

The invention discloses a traceless modification method of bacillus subtilis genome. The method disclosed by the invention is used for carrying out traceless modification on the bacillus subtilis genome by utilizing an upp positive-negative selection system. The method disclosed by the invention utilizes a ComK expression system, so that the bacillus subtilis has an excellent dsDNA (double-stranded deoxyribonucleic acid) conversion efficiency which can be up to 3-5*10<3>cfu/microgram dsDNA. Meanwhile, an exogenous endonuclease I-SceI expression system is utilized to bring double-stranded DNA breakage into the genome, so that the genetic recombination efficiency in negative selection molecules is obviously improved and can be up to 8*10<-4>. According to the method disclosed by the invention, iterative modification can be performed on a plurality of target nucleotide sequences in the bacillus subtilis genome, and the steps of introducing gene mutation to the genome, knocking out target gene sequences from the genome, deleting a large fragment of genomic sequences and the like are included.

The present invention relates to the treatment of cancer with compounds that inhibit the activity of endo-exonuclease. Endo-exonuclease has been shown to be necessary for the repair of damaged DNA. Compounds that inhibit the activity of endo-exonuclease have been shown to be particularly effective for treating cancer when used in combination with drugs that induce DNA breaks such as cisplatin and mitomycin C. These compounds have a synergistic effect when used in combination for inhibiting tumour growth. The invention includes pharmaceutical compositions for inhibiting tumour growth comprising a compound that inhibits endo-exonuclease activity. These pharmaceutical compositions preferably include compounds that induce DNA breaks. The invention includes methods of treating cancer with these pharmaceutical compositions and uses of these compositions to treat cancer. The preferred compounds that inhibit the activity of endo-exonuclease have low toxicity. One such compound is pentamidine. The invention also includes a method for diagnosing cancer and monitoring its progression. This aspect of the invention involves isolating serum from a patient; measuring the concentration of endo-exonuclease in said serum and determining whether said concentration is above a predetermined mean.

It is an object of the present invention to increase the biomass quantity of plants by causing an exogenous gene to be carried in plant cells. An exogenous gene that promotes double-stranded DNA breakage is introduced into the cells of a plant, and the plant is grown.

The invention relates to a method for detecting a PAS (Poly A Site) of an RNA (Ribose Nucleic Acid), and provides a method for analyzing APA (Alternative Polyadenylation) based on 3T-seq (TT-mRNA Terminal Sequencing) within a whole-genome range. The method for analyzing APA comprises the following steps: preparing magnetic beads containing oligo dT, i.e., mixing an oligo dT primer modified by 5' end biotin and the magnetic beads with streptavidin; mixing the magnetic beads with total RNA and screening RNA containing Poly A; performing reverse transcription, synthesizing the second strand of a double-stranded cDNA and breaking the double-stranded cDNA; removing the Poly A structure; after terminal modification, connecting a sequencing linker; and recovering libraries. According to the method for analyzing APA, RNA horizontal operation is reduced, a Poly A sequence is horizontally removed from the DNA, and the influence of the Poly structure on sequencing is eliminated; double-stranded DNA breaking enzyme is selected for treatment, and on the premise that the quality of the libraries is not affected, the DNA is broken horizontally; the experiment process is simplified, the experiment difficulty and cost are lowered and the method for analyzing APA is wide in application range.

The invention relates to the technical field of molecular biology and particularly relates to a novel methylation library-establishing kit and an application thereof. The novel methylation library-establishing kit at least comprises a bisulfate conversion reagent, a sticky end joint, ligase, a DNA extending reagent and a DNA amplifying reagent. The novel methylation library-establishing kit can beapplied to a sample with a low initial mass (as low as 6pg) and suitable for genome DNA with relatively poor mass extracted from FFPE samples and the like, so that the loss of sample information caused by DNA breakage during drug treatment is greatly reduced; and a double-chain DNA joint with a sticky end can be directly introduced by virtue of relatively economic and practical common ligase, sothat the accuracy of data can be improved, the diversity of samples can be preserved to a great extent, and the library deviation property caused by human factors can be reduced.

The invention relates to a method for screening and evaluating genetic toxicity of industrial wastewater with complex ingredients. Gemmiparous broad bean seeds are cultivated in a suspension manner in to-be-detected wastewater solution prepared with tap water by means of gradient dilution; after two weeks, root tips are cut down and placed in proteinase K solution, and vacuumizing is carried out. Root tip cell nucleuses are separated, and the single-cell gel electrophoresis (SCGE) technique is used for separating DNA fragments. A fluorescence microscope is used for shooting comet pictures. A cometscore image-analysis system is used for measuring the tail length and the tail moment of the comet. Then, an SPASS program is used for statistic analysis. The method promotes proteinase K to penetrate into root tip meristem cell nucleuses by means of vacuumizing, accelerates degradation of DNA crosslinked protein, thus removes retardation of DNA-protein cross-linking on DNA fragments, and facilitates revelation and accurate evaluation of the true level of NDA breakage and damage inducted by the to-be-detected wastewater.

The invention relates to the technical field of molecular biology and in particular relates to a novel methylation library construction method and an application thereof. The novel methylation libraryconstruction method provided by the invention is suitable for single-strand connection, amplification or library construction of a DNA sample treated by using bisulfite. Due to the adoption of a method for bisulfite treatment and then adhesive end joint connection, sample information loss caused by DNA breakage resulted from drug treatment is greatly reduced.

The invention relates to the technical field of anticancer drugs, in particular to a ruthenium complex anticancer drug and a preparation method thereof. The ruthenium complex anticancer drug is activated through redox, inserted into tumor cell DNA, and coordinated with DNA to undergo a crosslinking reaction, so as to prevent DNA replication and DNA breakage. Due to the introduction of a planar structure ligand, namely, 1,8-naphthalic anhydride, the binding capacity of the drug to DNA is enhanced by 14.17 times, and the stability and anti-tumor activity of the anticancer drug are greatly improved.

The invention discloses a novel tetracyclonaphthooxazole derivative. The structure of the novel tetracyclonaphthooxazole derivative is represented by general formula (I) shown in the specification. The invention also discloses a preparation method of the tetracyclonaphthooxazole derivative. The method allows the tetracyclonaphthooxazole derivative to be innovatively synthesized through using a carbon hydrogen activation serial reaction with amino substituted quinone as a reaction substrate. The method has the advantages of simplicity, easy implementation and high efficiency. The synthetic tetracyclonaphthooxazole derivative has a similar structure with a traditional DNA clastogen, can inhibit cell proliferation and growth, and has antibacterial, antifungal, anti-HIV and antitumor bioactivity. The invention also discloses an application of above compounds as a cell proliferation and growth inhibitor, and an application of the compounds in the preparation of antitumor medicines.

The invention relates to a method for rapid detection of in vitro DNA break damage strength by plasma, and the method is used for determining the damage strength of plasma mutagenesis methods including atmospheric and room temperature plasma (ARTP) on DNA. The method includes the steps of: 1) treating DNA coated microspheres by plasma mutagenesis method, and setting a control group without plasma treatment; 2) performing washing, and then dyeing the DNA coated microspheres with a dye; 3) determining the fluorescence value of the dyed DNA coated microspheres by a fluorescence detector; and 4) calculating the DNA relative content of the control group and the plasma mutagenesis treated microspheres according to the fluorescence value, and judging the gene damage strength of plasma. The invention utilizes DNA coated microspheres to establish a rapid detection method for in vitro DNA damage strength so as to realize direct and effective evaluation of plasma caused damage strength to DNA.

The invention belongs to the technical field of engineering, and particularly relates to a bacterial genome multi-editing method and application thereof. The bacterial genome multi-editing method based on double-stranded DNA recombinant engineering comprises the following steps: (1) mixing dsDNA substrates targeting different target sequences, and introducing the mixed dsDNA substrates into host competent cells with recombinase plasmids; (2) recovering the competent cells at the temperature lower than the optimum growth temperature; dNTPs with the final concentration of 10 nM is added in the resuscitation process; and (3) screening out a single colony with a marker from the recovered competent cells, and identifying. The method has the advantages that the substrate preparation cost is low, the length of the inserted gene is not limited, the method is not dependent on double-stranded DNA breakage, a plurality of guide RNA expression vectors do not need to be constructed, and a restrictive repair system of host bacteria does not need to be inactivated.

A method of modifying the genome of an organism, wherein the modification method includes modifying the genome of the organism by using in a cell of the organism a protein having an optimal temperature for double-stranded DNA breakage activity in an ordinary temperature region.

Provided is a genome shuffling technology suited to creating a useful next-generation plant body.

Genome shuffling is performed using a polypeptide comprising a first polypeptide region for double-stranded DNA breakage activity and a second polypeptide region for intertissue migration activity.

The invention provides a DNA sample treating method, a sequencing method and a kit. The method for treating a DNA sample comprises the following steps: performing fragmentation, terminal repair and dAtail addition on DNA in a first premixed system to obtain a first product, wherein the first premixed system comprises premixed enzyme, and the premixed enzyme comprises DNA fragmentation enzyme, polynucleotide kinase and DNA polymerase. Based on test experiments and an optimized mixed enzyme system, multiple enzymes are mixed in the same reaction system, DNA breakage, terminal repair and dA tailaddition are realized in one step, the convenience and rapidness are achieved, the operation time of sample treatment before loading is saved, and therefore the industrialization is facilitated.

The invention discloses a new application of astragalus polysaccharide, and belongs to the technical field of biology medicine. A basis is provided for preventing and treating myoblastosis through radix astragali. The inventor of the invention finds that the astragalus polysaccharide can obviously reinforce the proliferation activity of human BM-MSCs in formaldehyde environment, and can reduce DNAfragmentation and DPCs formation of human BM-MSCs induced by formaldehyde so as to have good protection effects. The astragalus polysaccharide can promote DNA injury repair factors of XPA, XPC, ERCC1, RPA1 and RPA2 mRNA and protein expression, and improve DNA damage repair capacity. The inventor finds that the astragalus polysaccharide can reinforce the proliferation activity of human BM-MSCs inthe formaldehyde environment for the first time, can reduce the DNA fragmentation effects of the human BM-MSCs in the formaldehyde environment and can reduce the DPCs formation of the human BM-MSCs inthe formaldehyde environment.