32 results about "Molecular cytogenetics" patented technology

The invention discloses a poplar root tip 3D fluorescence in-situ hybridization method based on paraffin sections, and belongs to the field of molecular cytogenetics. The poplar root tip 3D fluorescence in-situ hybridization method mainly includes the steps that tender root tips of poplar are obtained and fixed with Carnoy fluid; n-butanol gradient solution dehydrating, dipping wax and embedding are carried out; section slicing, section spreading, section baking and dewaxing are carried out; section preparation adopts pectinase, cellulase, pepsin and RNase for treatment; section preparation, probe denaturation and hybridization overnight are carried out; and hybridization signals are detected after incubation with secondary antibodies is carried out. The poplar root tip 3D fluorescence in-situ hybridization method can obtain clear FISH signals of the poplar root tip paraffin sections, and 3D images captured by a laser scanning confocal microscope can accurately reflect the three-dimensional level spatial distribution of a target sequence in cells. The poplar root tip 3D fluorescence in-situ hybridization method can be used in research fields such as chromosomal space occupation ofpoplar, gene expression and analysis of Hi-C sequencing results, and has broad application prospects.

The present invention relates to the technical fields of bioinformatics and molecular cytogenetics, and in particular to a new method for accurately counting chromosomes by using sugarcane centromere-specific repeat sequences, comprising the following steps: step 1, obtaining centromere-specific repeat sequences of the genus Sugarcane ; Step 2, separating the Saccharum centromere repeat sequence and carrying out counting analysis; the present invention utilizes the chromatin immunoprecipitation of the Saccharum centromere-specific histone and the high-throughput sequencing technology (ChIP-Seq) to obtain The DNA sequence of the centromere region of sugarcane was obtained; through comparative analysis, the repetitive sequence in the centromere region of different sugarcane species was screened out; primers were designed according to the sequence, amplified and labeled for mitotic metaphase fluorescence in situ hybridization (FISH) , for chromosome counting. The results showed that this sequence produced specific and clear and bright signals in the centromere region of all chromosomes of different sugarcane species; the number of chromosomes of different materials could be quickly and accurately obtained by counting the number of centromere signals.

The invention belongs to the field of molecular cytogenetics and particularly relates to a BAC-FISH method for simultaneously identifying whole sets of chromosomes of subgroups under a gossypium AD / ADE background. The method comprises the following steps: carrying out BAC-FISH on different cotton seeds by using BAC cloned 57I23 originated from an Africanum BAC library, and simultaneously identifying chromosomes of an AD genome and AD sub genome of cotton obviously; by using BAC-DNA as a probe, covering most regions out of ends of all chromosomes of the subgroup A in five gossypium tetraploids as well as a small region near the middle part of the all chromosomes of the subgroup D by a hybrid signal; and in allohexaploid hybrids AADDEE hybridized by upland cotton and G.stocksii (E1) in the group E, as the hybrid signal is similar to the tetraploid, obviously differentiating the hybrid signal from the subgroup E (without a signal) so as to simultaneously identify three sets of chromosomes of subgroups (A,D,E). By adopting the BAC-FISH method through BAC cloning, the whole sets of chromosomes of subgroups under the gossypium AD / ADE background can be simultaneously identified.

The invention belongs to the field of molecular cytogenetics, and in particular relates to a method for re-hybridizing a FISH film. The method mainly comprises the following steps: soaking the film into 2*SSC to wash away a cover plate after first fluorescence in situ hybridization (FISH), and then soaking the treated film in 2*SSC for 3*5min; putting the film into 2*SSC of 90 DEG C for 10min while shaking continuously; putting the film into 70% deionized formamide of 78 DEG C for 4min while shaking continuously; and quickly putting into 70% alcohol of -20 DEG C. A hybridization signal can be washed away by adopting the method, and then the hybridization signal cannot be detected by observing the film. When the treated film is reused for a FISH experiment by adopting the same probe, the hybridization signal can be detected again at the same position of a chromosome. By adopting the method, the film subjected to in situ hybridization can be reused, so that resources are effectively saved, the cost is reduced and the environmental pollution is reduced.

The invention belongs to the technical field of crop molecular cytogenetics, and in particular relates to a method for fluorescent in situ hybridization of Chinese cabbage mature pollen cells. The method comprises steps of determining flower buds in a Chinese cabbage mature pollen stage, preparing a mature pollen cell sheet, conducting probe labeling, conducting in situ hybridization, conducting signal detection and the like. The method provided by the invention is characterized in that the flower buds before 1-2d of blossoming of Chinese cabbage are prepared, fresh pollen grains are separated from the flower buds in a 50% glacial acetic acid solution, and pollen walls are broken by virtue of vertical tabletting, so that complete vegetative cells and generative cells are released; cell samples, which are pre-processed, are denatured together with a denaturation probe at 80 DEG C for 3min, and the in situ hybridization is directly conducted, so that a fluorescent hybridization picture that signals are clear is obtained, showing a signal difference of target DNA in the vegetative cells and generative cells. The method provided by the invention fills a technical gap in fluorescent in situ hybridization of mature pollen cells of brassica plants; and the method is applicable to molecular cytogenetics study on pollen development of the Chinese cabbage.

The invention discloses an antigenic polypeptide of poplar functional centromere histone CENH3 and application thereof, belonging to the fields of bioinformatics and molecular cytogenetics. The invention mainly includes: screening a specific amino acid sequence of Populus trichocarpa CENH3 protein and artificially synthesizing the polypeptide, using the polypeptide to immunize New Zealand rabbits, preparing antiserum, and obtaining CENH3 protein antibody after affinity purification; the antibody is detected by immunofluorescence, ChIP-FISH Specificity verification proved that the antibody can accurately identify functional centromeres. The antibody can be used universally in poplar species, not only can accurately mark the position of poplar functional centromere, but also lay a foundation for the study of the structure, function and evolution of poplar centromere. The invention has broad application prospects in the research fields of poplar molecular cytogenetics, genomics, epigenomics and the like.