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伊恩·维尔穆特 《科技导报(北京)》2019,37(2):29-30
从1865年到世界上首个克隆动物--"克隆羊"诞生的100多年间,人类一直在进行相关研究。有一个问题直到现在仍未得到完全的回答--人类来自于一个单一的细胞,但现在还不完全清楚的是,这样一个单个细胞是如何产生胚胎并形成其他器官的。1865年,著名科学家韦斯曼(Weissmann)认为,细胞的分裂是不平均的,这样导致在细胞分裂之后所获得的结果有各自不同的特点。那么,把细胞分离进行移植到底会产生什么样的结果?正是这样一种对换,导致了克隆技术的研发和发展。 相似文献
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Analysis of telomere lengths in cloned sheep. 总被引:33,自引:0,他引:33
P G Shiels A J Kind K H Campbell D Waddington I Wilmut A Colman A E Schnieke 《Nature》1999,399(6734):316-317
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Epigenetic change in IGF2R is associated with fetal overgrowth after sheep embryo culture 总被引:35,自引:0,他引:35
Young LE Fernandes K McEvoy TG Butterwith SC Gutierrez CG Carolan C Broadbent PJ Robinson JJ Wilmut I Sinclair KD 《Nature genetics》2001,27(2):153-154
Manipulation or non-physiological embryo culture environments can lead to defective fetal programming in livestock. Our demonstration of reduced fetal methylation and expression of ovine IGF2R suggests pre-implantation embryo procedures may be vulnerable to epigenetic alterations in imprinted genes. This highlights the potential benefits of epigenetic diagnostic screening in developing embryo procedures. 相似文献
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Production of pharmaceutical proteins in milk 总被引:2,自引:0,他引:2
I Wilmut A L Archibald M McClenaghan J P Simons C B Whitelaw A J Clark 《Experientia》1991,47(9):905-912
There is every reason to expect that it will be possible within the next few years to begin to use farm animals to produce large quantities of some of the human proteins that are needed for the treatment of disease. Revolutionary new opportunities for the production of novel proteins in milk have been created by the development of methods for gene transfer. Exploitation of these opportunities depends upon selection and cloning of milk protein genes and identification of the sequences that govern tissue specific hormonally induced expression in the mammary gland. Studies with three genes, ovine beta-lactoglobulin, rat beta-casein and whey acidic protein of rat and mouse, suggest that they may all meet this requirement. Fragments of the ovine beta-lactoglobulin, murine whey acidic protein and rabbit beta-casein genes have directed production of novel proteins in the milk of transgenic mice, sheep, rabbits and pigs. The proteins were biologically active and usually co-migrated with authentic proteins. In early experiments, protein concentration was low, but our recent observations suggest that fusion genes containing genomic clones direct production of concentrations of protein that are suitable for commercial exploitation. In the longer term, two approaches may offer the potential of more reliable expression. Control elements capable of directing expression that is independent of site of insertion of the gene, but dependent on the number of copies of the gene, have been identified for a small number of genes. The availability of such elements for the milk protein genes would increase the reliability of gene expression considerably. Alternatively, targeted mutation of genes may allow the insertion of coding sequences within an existing gene so avoiding position effects. 相似文献
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Production of pharmaceutical proteins in milk 总被引:1,自引:0,他引:1
I. Wilmut A. L. Archibald M. McClenaghan J. P. Simons C. B. A. Whitelaw A. J. Clark 《Cellular and molecular life sciences : CMLS》1991,47(9):905-912
There is every reason to expect that it will be possible within the next few years to begin to use farm animals to produce large quantities of some of the human proteins that are needed for the treatment of disease. Revolutionary new opportunities for the production of novel proteins in milk have been created by the development of methods for gene transfer. Exploitation of these opportunities depends upon selection and cloning of milk protein genes and identification of the sequences that govern tissue specific hormonally induced expression in the mammary gland. Studies with three genes, ovine -lactoglobulin, rat -casein and whey acidic protein of rat and mouse, suggest that they may all meet this requirement. Fragments of the ovine -lactoglobulin, murine whey acidic protein and rabbit -casein genes have directed production of novel proteins in the milk of transgenic mice, sheep, rabbits and pigs. The proteins were biologically active and usually co-migrated with authentic proteins. In early experiments, protein concentration was low, but our recent observations suggest that fusion genes containing genomic clones direct production of concentrations of protein that are suitable for commercial exploitation. In the longer term, two approaches may offer the potential of more reliable expression. Control elements capable of directing expression that is independent of site of insertion of the gene, but dependent on the number of copies of the gene, have been identified for a small number of genes. The availability of such elements for the milk protein genes would increase the reliability of gene expression considerably. Alternatively, targeted mutation of genes may allow the insertion of coding sequences within an existing gene so avoiding position effects. 相似文献
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Somatic cell nuclear transfer 总被引:30,自引:0,他引:30
Wilmut I Beaujean N de Sousa PA Dinnyes A King TJ Paterson LA Wells DN Young LE 《Nature》2002,419(6907):583-586
Cloning by nuclear transfer from adult somatic cells is a remarkable demonstration of developmental plasticity. When a nucleus is placed in oocyte cytoplasm, the changes in chromatin structure that govern differentiation can be reversed, and the nucleus can be made to control development to term. 相似文献
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