【摘 要】
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Parthenogenetic embryos,created by activation and diploidization of oocytes,arrest at mid-gestation for defective paternal imprints,which impair placental development.Also,viable offspring has not been obtained without genetic manipulation from partheno-g
【机 构】
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State Key Laboratory of Medicinal Chemical Biology,Nankai University,Tianjin 300071,China;Department
论文部分内容阅读
Parthenogenetic embryos,created by activation and diploidization of oocytes,arrest at mid-gestation for defective paternal imprints,which impair placental development.Also,viable offspring has not been obtained without genetic manipulation from partheno-genetic embryonic stem cells (pESCs) derived from parthenogenetic embryos,presumably attributable to their aberrant imprinting.We show that an unlimited number of oocytes can be derived from pESCs and pro-duce healthy offspring.Moreover,normal expression of imprinted genes is found in the germ cells and the mice.pESCs exhibited imprinting consistent with exclusively maternal lineage,and higher X-chromosome activation compared to female ESCs derived from the same mouse genetic background.pESCs differentiated into primordial germ cell-like cells (PGCLCs) and formed oocytes fol-lowing in vivo transplantation into kidney capsule that produced fertile pups and reconstituted ovarian endo-crine function.The transcriptome and methylation of imprinted and X-linked genes in pESC-PGCLCs closely resembled those of in vivo produced PGCs,consistent with efficient reprogramming of methylation and genomic imprinting.These results demonstrate that amplification of germ cells through parthenogenesis faithfully maintains maternal imprinting,offering a promising route for deriving functional oocytes and having potential in rebuilding ovarian endocrine function.
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