35 results about "Genetic strain" patented technology

The invention belongs to the field of molecular biology, and discloses application of a segment of isolated nucleotide sequence in construction of zebra fish with reduced intramuscular spines. The nucleotide sequence is shown as SEQ ID NO.1, by using a conventional method in the field, the SEQ ID NO.1 is taken as a target gene to perform gene mutation operation, F0 with mutation is screened out, F1 generated by hybridization of F0 and a wild type is subjected to genotyping, and mutant F1 is screened out and selfed, so that the zebra fish strain with few intramuscular spines which is remarkablyreduced by more than 70% in the number of intramuscular spines and is stably inherited can be obtained. According to the application of the segment of isolated nucleotide sequence in construction ofzebra fish with reduced intramuscular spines, the segment of isolated nucleotide sequence is used to obtain a fish strain with reduced intramuscular spines for the first time, and the application of the segment of isolated nucleotide sequence in construction of zebra fish with reduced intramuscular spines has the advantages of remarkable character improvement effect, short breeding time, stable heredity, low cost and the like, has the basic value and the application value of scientific research, can be used for researching the development mechanism of the intramuscular spines of the fish, andprovides a method for obtaining a stable genetic strain with few intramuscular spines of various fish.

The invention discloses a method for breeding leaf mustard type rape varieties and materials by a rape double haploid inducing line. The method comprises the following steps: firstly, determining objective traits of the bred leaf mustard type rape varieties and materials; secondly, performing hybridization, convergent cross or backcross on at least two leaf mustard type rapes with the objective traits; thirdly, pollinating progenies obtained by hybridization, convergent cross or backcross by using the rape double haploid inducing line; fourthly, identifying the genetic stability of induced progenies, and realizing selfing breeding according to strains; fifthly, identifying the yield, resistance and quality traits of induced stable progeny strains; sixthly, determining the stable strains according to the yield, the quality traits and the resistance to form a conventional variety of leaf mustard type rape; seventhly, inducing stable progeny genetic strains to form a new leaf mustard type rape line and performing test cross on the new leaf mustard type rape line and a leaf mustard type rape sterile line to form a maintainer line or restorer line, or entering next round of breeding process of the varieties and materials. According to the method, the breeding speed and efficiency of a hybrid variety or a conventional variety of the leaf mustard type rape can be greatly improved, and labor force and material resources are reduced.

The present invention discloses a safe and environmentally friendly cichorium intybus chloroplast transformation system establishment method, which comprises: (1) establishing a high frequency regeneration system of a cichorium intybus leaf explant; (2) constructing a safe and environmentally friendly cichorium intybus chloroplast site-specific integration expression vector; and (3) adopting a gene gun bombardment method to transform the cichorium intybus explant, and carrying out three rounds of resistance screening to obtain the chloroplast transgene strain. According to the present invention, the novel safe selection marker gene PMI is adopted to replace the traditional antibiotic marker gene aadA to construct the chloroplast site-specific integration expression vector and establish the cichorium intybus chloroplast transformation system, wherein the system has advantages of high screening efficiency, high exogenous gene expression level, strong transgenic plant bio-safety and the like; and receptor types of chloroplast transformation are broadened, and technical platforms are built for genetic improvement on cichorium intybus, or application of cichorium intybus chloroplast as a bioreactor to produce animal oral vaccines, medical proteins and the like.

The invention discloses brassica napus L promoter pBnUnng0942890 and application thereof. By cloning a promoter of a gene pBnUnng0942890 in the brassica napus L, a plant expression vector of a reporter gene GUS regulated by the promoter is constructed; by using an agrobacterium-mediated inflorescence impregnating method to transform arabidopsis, GUS histochemical staining is carried out on screened positive transgenic strains; the result shows that the pBnUnng0942890 has the functions of driving preferential expression of downstream genes in roots, flowers and seeds, and not expressing or realizing low expression in other tissues and organs. The promoter has good application potential in the aspects of improving crop quality by rapeseed transgene, artificially creating germplasm resourcesand the like.

The invention discloses a selection method for a good genetic strain of sophora japonica, and belongs to the technical field of tree good strain selection. The method is capable of solving the problemin the prior art that the good genetic strain of the sophora japonica cannot be selected. The method comprises the following steps: after the primary selection and repeated selection, selecting superior trees, marking the superior trees, and breeding the superior trees through grafting and budding; and after the bred superior trees are in the full bearing period, performing the contrastive analysis to all tested clones, and selecting the superior tree clones which can keep the female parent good feature or achieve the local main cultural variety standard as the good strains. The method is capable of improving the variety rate of the sophora japonica, and optimizing the sophora japonica resources.

The invention belongs to the field of plant transgenosis and relates to a method for rapid screening of a single copy transgenic offspring homozygous family and a use thereof. A carrier is conversed through an agrobacterium-mediated genetic transformation method, a positive single copy transgenic plant is screened through southern, seeds of the T0 generation of the transgenic plant are collected and then are sowed in a seed bed, leaves in a trefoil stage are collected, total DNAs of a hand sample are extracted through a CTAB method, real-time PCR primers are designed according to an exogenous target gene hygromycin and an endogenous G3PDH gene, the hand sample DNA is subjected to real-time PCR through the primers of the exogenous target gene and the endogenous gene, amplification Ct values of the exogenous target gene and the endogenous gene are calculated and compared, a transgenic plant genotype is determined through the amplification Ct values, after the T1 generation of the plants produce fruits, a transgenic plant genotype is detected through germination, the above two transgenic plant genotypes are compared, and the two materials with the identical genotypes are used as transgenic breeding, hybridization transformation breeding or polygene pyramiding breeding materials.

The invention discloses an artificial recombinant H5N8 influenza virus and a preparation method and application thereof. The artificial recombinant H5N8 influenza virus has a highly pathogenic avian influenza virus A/swan/Shanxi/4-1/2020 (H5N8) surface antigen Hemagglutinin (HA) gene and a Neuraminidase (NA) gene, but an HA cleavage site has a typical low pathogenic avian influenza virus molecular characteristic (-RETR-), and has six internal genes of PB2, PB1, PA, NP, M and NS of an influenza virus chick embryo high-titer adaptive strain A/PR/8/34(H1N1), the strain number is H5-Re14, and the preservation number is CCTCC NO: V202160. The artificial recombinant H5N8 influenza virus has good chick embryo adaptability, and the virus growth titer can be increased by 9 times or above compared with that of a wild virus; and the artificial recombinant H5N8 influenza virus is used as a vaccine strain for producing a vaccine, the production cost of the vaccine can be greatly reduced, and the quality of the vaccine is improved.

The invention discloses an artificial recombinant H7N9 influenza virus and a preparation method and application thereof. The artificial recombinant H7N9 influenza virus has a highly pathogenic avian influenza virus A/chicken/Yunnan/SD024/2021(H7N9) surface antigen Hemagglutinin (HA) gene and a Neuraminidase (NA) gene, but the amino acid sequence of the HA cleavage site is -PKGR-, the virus has six internal genes of PB2, PB1, PA, NP, M and NS of influenza virus A/PR/8/34(H1N1), the strain number is H7-Re4, and the preservation number is CCTCC NO: V202161. The strain has good chick embryo adaptability, and the virus growth titer can be increased by 9 times or above compared with that of a wild virus; the strain is used as a vaccine strain to produce vaccines, the production cost of the vaccines can be greatly reduced, and the quality of the vaccines is improved.

An isolated zebrafish genetic strain having a dystrophin mutant phenotype and fish models useful for screening or assaying agents having potential activity on muscular dystrophy or cardiomyopathy.

The invention relates to a rice female genic male sterility gene engineering expression vector and application thereof, and belongs to the technical field of agricultural biology. In order to realize the breeding of seeds and seedlings of the rice female genic male sterile line, the invention provides a technical means of transgene transfer deletion to realize the breeding of a non-transgene homozygous female genic male sterile line. Specifically, after selfing and fruiting of a genetic engineering female genic male sterile line, namely a hybrid type transgenic T0 strain, a transgenic T1 segregation population is obtained, in the seedling stage of the transgenic T1 segregation population, transgenosis female fertility recovery plants are screened out by spraying bentazone herbicide, and survival T1 plants are non-transgenosis female genic male sterile (fst/fst) plants. The non-transgenic female genic male sterile line can meet the mechanical seed production operation of a hybrid rice seed production technical system of 'FS + MS (FM-line)', namely 'female sterile line + male sterile line (FM line method)'.

The invention belongs to the technical field of plant genetic engineering, and particularly relates to a carrier for delaying fragaria X ananassa Duch. leaf senescence and an application thereof. An RNA interference fragment of a fragaria X ananassa Duch. cytokinin receptor gene FveHK4 is screened from fragaria X ananassa Duch.; a plant inhibition expression vector GN2300-FveHK4 of the gene is constructed and is transferred into diploid fragaria X ananassa Duch. 'Hawaii 4', and an RNAi expression interference strain of the FveHK4 gene is obtained, wherein vegetative growth of the strain is notobviously different from vegetative growth of a wild type. Under a dark condition, compared with a wild type, senescence of the FveHK4-RNAi in-vitro leaves is obviously delayed, which shows that thesenescence speed of the leaves of the fragaria X ananassa Duch. transgenic line of the genetic transformation FveHK4 interference carrier is slowed down, and the functional period is prolonged. The carrier has important significance in delaying strawberry leaf senescence, increasing the photosynthetic production of leaves and further increasing the strawberry yield.