The experiments of serial nuclear transfer were conducted between Boer goat and rabbit. The enucleated oocytes of rabbit were used as recipients while the blastomeres of goat morula was used as nuclear donor. The reco...The experiments of serial nuclear transfer were conducted between Boer goat and rabbit. The enucleated oocytes of rabbit were used as recipients while the blastomeres of goat morula was used as nuclear donor. The reconstructed embryos developing to morula were used as donor for serial cloning. As a result, two generations of reconstructed embryos were obtained, including 58 first generation reconstructed embryos and 14 second generation reconstructed embryos. The fusion rates were 79.5 and 70%, respectively, and there was no significant difference between them （P〉0.05）. The cleavage rates were 75.9 and 28.6% respectively with significant difference （P〈0.01）. No blastocyst was obtained from the second generation reconstructed embryos while 13.8% of first generation reconstructed embryos developed to blastocyst.展开更多
Interspecies somatic nuclear transfer (NT) may provide a new approach for preservation of the endangered rare species. Previous interspecies cloning studies have shown that a nucleus from a quiescent somatic cell supp...Interspecies somatic nuclear transfer (NT) may provide a new approach for preservation of the endangered rare species. Previous interspecies cloning studies have shown that a nucleus from a quiescent somatic cell supports early development of reconstructed embryos in the ooplasm from another species. In this study, we transferred nonqui-escent somatic cells from a giant panda into the perivitelline space of the enucleated rabbit oocytes. After electrofusion (at the rate of 71.6%) and electrical activation, 4.2% of the panda-rabbit reconstructed embryos developed to blastocyst in vitro. For improving the development rate of reconstructed embryos, we used serial NT in this study, i.e. blas-tomeres from reconstructed morulae were transferred into the perivitelline space of the enucleated rabbit oocytes. The fusion rates in the groups of serial I, serial Ⅱ and serial Ⅲ were 79.5%, 84.1% and 78.0%, respectively, having no difference with that of somatic group. And the blastocyst rates in serial NT groups展开更多
In order to investigate the effects of different kinds of nuclear recipients from Kunming (KM) mouse on developmental potential of somatic nuclear transfer em- bryos, the enucleated MⅡ oocytes, enucleated zygotes and...In order to investigate the effects of different kinds of nuclear recipients from Kunming (KM) mouse on developmental potential of somatic nuclear transfer em- bryos, the enucleated MⅡ oocytes, enucleated zygotes and 2-cell blastomere were used to produce cloned mouse em-bryos. Using fibroblast deriving from C57/BL6 ear tissue as nuclear donor, we produced cloned embryos by transferring the fibroblast nuclei into enucleated KM mouse oocytes (sin-gle nuclear transfer, SNT), transferring pronuclei from the SNT embryos into enucleated KM zygotes (nuclear into zy-gote, NZ), and 2-cell blastomere nuclei from SNT embryos into enucleated KM mouse oocytes (nuclear into oocytes, NO); tetraploid embryos (tetraploid embryos, TE) were ob-tained by fusing two blastomeres, one is from the SNT cloned embryos, and the other from normal 2-cell KM mouse em-bryos. In group SNT, the cloned embryos could not develop beyond 8-cell stage and the rate of 8-cell stage is only 0.3%; in group NO, the reconstructed embryos could develop to morula stage, the rate of 8-cell stage was significantly greater than that of SNT group (P < 0.05); in group NZ, the devel-opment rate was further improved, and the reconstructed embryos could develop into blastocyst stage, the rate of blastocyst was 1.9%; in group TE, as high as 62.3% of the reconstructed embryos could develop into blastocyst. Results suggested that different nuclear recipients could significantly affect the developmental potential of cloned mouse embryos; KM MⅡ oocyte cytoplasm was not so effective as zygotes to reprogram the mouse somatic cell nuclei; serial nuclear transfer could improve the developmental potential of cloned mouse embryos.展开更多
文摘The experiments of serial nuclear transfer were conducted between Boer goat and rabbit. The enucleated oocytes of rabbit were used as recipients while the blastomeres of goat morula was used as nuclear donor. The reconstructed embryos developing to morula were used as donor for serial cloning. As a result, two generations of reconstructed embryos were obtained, including 58 first generation reconstructed embryos and 14 second generation reconstructed embryos. The fusion rates were 79.5 and 70%, respectively, and there was no significant difference between them （P〉0.05）. The cleavage rates were 75.9 and 28.6% respectively with significant difference （P〈0.01）. No blastocyst was obtained from the second generation reconstructed embryos while 13.8% of first generation reconstructed embryos developed to blastocyst.
基金This work was supported by the Climbing Project of the Ministry of Sciences and Technology of China (Grant No.97021109-2)the Important Project of Knowledge Innovation of Chinese Academy of Sciences (Grant No. KSCX1-05-01).
文摘Interspecies somatic nuclear transfer (NT) may provide a new approach for preservation of the endangered rare species. Previous interspecies cloning studies have shown that a nucleus from a quiescent somatic cell supports early development of reconstructed embryos in the ooplasm from another species. In this study, we transferred nonqui-escent somatic cells from a giant panda into the perivitelline space of the enucleated rabbit oocytes. After electrofusion (at the rate of 71.6%) and electrical activation, 4.2% of the panda-rabbit reconstructed embryos developed to blastocyst in vitro. For improving the development rate of reconstructed embryos, we used serial NT in this study, i.e. blas-tomeres from reconstructed morulae were transferred into the perivitelline space of the enucleated rabbit oocytes. The fusion rates in the groups of serial I, serial Ⅱ and serial Ⅲ were 79.5%, 84.1% and 78.0%, respectively, having no difference with that of somatic group. And the blastocyst rates in serial NT groups
基金the Climbing Project of the Ministry of Science and Technology of China (Grant No. 97021109-2) and the Major Project of Knowledge Innovation of the Chinese Academy of Sciences (Grant No. KSCX1-05-01)
文摘In order to investigate the effects of different kinds of nuclear recipients from Kunming (KM) mouse on developmental potential of somatic nuclear transfer em- bryos, the enucleated MⅡ oocytes, enucleated zygotes and 2-cell blastomere were used to produce cloned mouse em-bryos. Using fibroblast deriving from C57/BL6 ear tissue as nuclear donor, we produced cloned embryos by transferring the fibroblast nuclei into enucleated KM mouse oocytes (sin-gle nuclear transfer, SNT), transferring pronuclei from the SNT embryos into enucleated KM zygotes (nuclear into zy-gote, NZ), and 2-cell blastomere nuclei from SNT embryos into enucleated KM mouse oocytes (nuclear into oocytes, NO); tetraploid embryos (tetraploid embryos, TE) were ob-tained by fusing two blastomeres, one is from the SNT cloned embryos, and the other from normal 2-cell KM mouse em-bryos. In group SNT, the cloned embryos could not develop beyond 8-cell stage and the rate of 8-cell stage is only 0.3%; in group NO, the reconstructed embryos could develop to morula stage, the rate of 8-cell stage was significantly greater than that of SNT group (P < 0.05); in group NZ, the devel-opment rate was further improved, and the reconstructed embryos could develop into blastocyst stage, the rate of blastocyst was 1.9%; in group TE, as high as 62.3% of the reconstructed embryos could develop into blastocyst. Results suggested that different nuclear recipients could significantly affect the developmental potential of cloned mouse embryos; KM MⅡ oocyte cytoplasm was not so effective as zygotes to reprogram the mouse somatic cell nuclei; serial nuclear transfer could improve the developmental potential of cloned mouse embryos.
