63 results about "Cloning embryos" patented technology

The invention discloses a method for breeding transgenic livestock rich in polyunsaturated fatty acid. The method comprises the following steps of: guiding DNA molecules which have a sequence 1 and a sequence 2 in a sequence list into somatic cells of a mammal to obtain transgenic cells in which a delta-12 fatty acid dehydrogenase and an omega-3 fatty acid dehydrogenase are expressed; cloning embryos by using the transgenic cells as nuclear transfer donor cells and using isolated ovocytes as nuclear transfer acceptor cells by nuclear transfer technology; and transplanting the cloned embryos into a uterus of the livestock by a non-operation method for gestation to obtain the transgenic livestock. The method of the invention can ensure that the delta-12 fatty acid dehydrogenase and the omega-3 fatty acid dehydrogenase are stably expressed in the body of a transgenic pig and that the content of omega-3 polyunsaturated fatty acids (PUFAs) in meat of the livestock is improved obviously.

The present invention provides a preparation method for an anti-porcine reproductive and respiratory syndrome cloned pig, comprising: transferring CRISPR / Cas9 targeting vectors and CD163 gene homologous recombination modification vectors into fibroblasts of a pig to obtain positive clone cells, a seventh exon of porcine endogenous CD163 gene being replaced with a eleventh exon of human CD163-L1 gene, so that the positive clone cells are incapable of mediating invasions of PRRSV; taking the positive cell as nuclear transfer donor cells and oocytes as nuclear transfer recipient cells to obtain a cloned embryo by adopting a somatic cell nuclear transfer technology; and impregenating a pig by transferring the cloned embryo into the uterus of the pig, to obtain a cloned pig.

The invention discloses a method for efficiently preparing high-quality cloned embryos, belonging to the field of embryo transplanting methods. The method provided by the invention comprises the following steps of: agitating and screening to obtain sheep oocytes in the same cell period and transplanting a supplier cell into the sheep oocytes through utilizing microscopy injection; then treating by utilizing a fusion solution and putting the treated embryo into a mature solution to be cultured to form a fused embryo; and chemically activating and then starting and reconstructing embryo cleavage. According to the method provided by the invention, the sheep oocytes which are in the same cell period and have the uniform mature time through an agitating method are acquired, a new method for picking the good sheep oocytes is provided and the mature rate of the sheep oocytes is improved. According to the method provided by the invention, the operation efficiency of nuclear transfer is improved by utilizing a method of simultaneously denucleating through extrusion and carrying out nucleus injection by utilizing the same injection needle. The fusion efficiency is improved to more than 95% by using the fusion solution which is developed by the method provided by the invention, the successful rate of the cloned embryo is greatly improved and the subsequent embryo development is not influenced. The method provided by the invention has the advantages of reducing the loss of the embryos in the process of preparing the cloned embryo and improving the efficiency of preparing the sheep cloned embryos; and the method provided by the invention is a method for efficiently preparing the sheep cloned embryos with good quality and has a wide application prospect.

The invention relates to the field of animal cloning methods, in particular to a method for improving the development efficiency of a porcine cloned embryo. The method mainly comprises the step of adding a uterine fluid of a sow into a basic culture solution for the porcine cloned embryo. By the method, the blastocyst rate during early development of the cloned embryo and the total number of cellsin a blastocyst are significantly increased; a transcriptome sequencing result of the early embryo shows that culture through addition of the uterine fluid of the sow reduces the number of differentially expressed genes between the cloned embryo and a normal in-vivo fertilized embryo; most importantly, through the addition of the uterine fluid of the sow, also increased the fertility rate of therecipient sow of the cloned embryos and the number of litters per litter, the parturition rate of a receptor sow with the cloned embryo and the number of live births are also increased, which means that by the method, the final efficiency of the in-vivo development of the cloned embryo is effectively improved.

The invention discloses a somatic cell cloning method for mammals such as cows, dogs or sheep and culture fluid utilized in the method. The method comprises following mammal somatic cell cloning embryo processing steps: (1) injecting to-be-transplanted mammal somatic cells into denucleated oocytes, carrying out electro-fusion, then selecting successfully fused mammal somatic cell cloning embryos in 1 hour after electro-fusion, and carrying out activation; and (2) after the activation, transferring the mammal somatic cell cloning embryos into G1.3 culture fluid, and carrying out culturing. The invention further relates to the culture fluid used in the method. The method disclosed by the invention presents the excellent technical effects described in the description.

The invention relates to a new function of a porcine BTG2 (B-cell translocation gene-2) in anti-PRRS (porcine reproductive and respiratory syndrome) virus, and in particular provides application of porcine BTG2 gene in anti-PRRS virus. The application is as follows: inhibiting replication of PRRS virus in cells by over-expression of BTG2 gene in cells. The invention also provides a method for screening an anti-PRRS virus pig by utilizing the expression quantity of BTG2 gene, and a method for preparing a cloned embryo of over-expressed BTG2.

The invention discloses a complete pig Xist (X inactive specific transcript) gene sequence and a method for improving the pig cloning efficiency. The pig Xist gene sequence is obtained through electronically cloning the pig Xist gene sequence by utilizing a biological informatics method and checking and analyzing the sequence. The method comprises the following steps of: designing and synthesizing anti-Xist siRNA (small interfering ribose nucleic acid) sequences, screening the effective anti-Xist siRNA sequence by utilizing a molecular biological technology, utilizing anti-Xist siRNA to inhibit nuclear transfer reconstructed embryos or Xist gene expression of nuclear transfer somatic cell donors so as to improve the development quality of pig cloning embryos, and thus realizing a purpose of improving the pig cloning efficiency. According to the method, the complete pig Xist sequence and the anti-Xist siRNA sequence are obtained at first; and moreover, by utilizing the method, the ectogenic quality of the pig cloning embryos can be improved, and the improved pig cloning efficiency has a significant meaning in the fields of livestock production, scientific research or medical science.

The invention discloses a method for in-vitro cloned embryo transplantation of a pregnant sow. The method comprises the following steps: feeding an estrus synchronization agent to each sow at a fixedpoint every day, after continuously feeding each sow with the estrus synchronization agent for 18 days, performing intramuscular injection of PG600 5 days later, and selecting an individual with normal estrus for in-vitro cloned embryo transplantation 1 day later. According to the method, a proper microenvironment is provided for the pregnant sow after the cloned embryo is transplanted by virtue of feeding or injection of the estrus synchronization agent and the PG600, synchronism of the estrus, ovulation and embryo transplantation time of the pregnant sow is controlled, and the success rate of cloned embryo implantation and the pregnancy rate of the pregnant sow are greatly increased, so that batch production of cloned pigs is realized, and a foundation is laid for large-scale productionof the cloned pigs.

The invention discloses a method for improving bovine somatic cell cloning efficiency. By inducing the expression of zfp57 gene, the methylation of imprinted genes in the development process of a bovine cloned embryo is restored to a normal level, so that the cloning efficiency of bovine somatic cells is improved. The method for improving the bovine somatic cell cloning efficiency provided by theinvention utilizes the zfp57 to correct the abnormal low methylation of imprinted genes on the bovine cloned embryo, and makes the methylation level close to that of in vitro fertilization embryos soas to improve the embryo quality of the bovine cloned embryos, and to promote the development of the bovine cloned embryos. The method provides a theoretical basis for clarifying the mechanism of abnormal methylation imprinting in the process of reprogramming somatic cell-cloned embryos, and the reason of low efficiency of somatic cell cloning.