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Triploid pluripotent stem cells. R eporter : XueBinghua Date : 2011.06.15. Human oocytes reprogram somatic cells to a pluripotent state. Scott Noggle & Dieter Egli Nature 1 August 2011. Background. Limit : Legal and social considerations Different : iPS and blastocyst-derived stem cells
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Triploidpluripotent stem cells Reporter:XueBinghua Date:2011.06.15
Human oocytes reprogram somatic cells to a pluripotent state Scott Noggle & Dieter Egli Nature 1 August 2011
Background • Limit:Legal and social considerations • Different:iPS and blastocyst-derived stem cells (gene expression,DNA methylation and differentiation potential) • Compromise: Genomic integrity (de novo mutations and copy number variations)
Results: 1、Development fails after somatic genome replacement
38/50 43/43 (12 without) Skin cells (♂T1D and ♂WT ) GFP CAGGS promoter:(H2B):GFP MII oocyte & Donor cell
35/35 Chromosome condensation
Normal cleavage :22/31(71%) Arrests at a stage of 6–10 cells Parthenotes:13/52 ( 25%) IVF:16/21(76%) Developmentalpotential & Development arrests
6-8h Control for the quality of the oocytes
32/32 4/7
Results: 2、Development arrests with transcriptional defects
6-12cells *ZGA starts at the 4–8 cell stage28, or on day 3 of development*Upregulatedtranscripts incomparison to unfertilized oocytes 761 transcripts upregulated at zygotic genome activation 124 (16%) were upregulated after genome exchange 62 (8%) were upregulated after amanitin treatment 536(70%) were upregulated at parthenotes*1,406 genes expressat higher levels in the skin donor fibroblasts than in MIIoocytesGADD45G is involved in stress-induced cell cycle arrest
Results: 3、The oocyte genome rescues development
Results: 4、Derivation of pluripotent stem cells
463/1327 670/1327 Global gene expression analysis &Up and down *463:Lin28a,Oct4,Sox2, Nanog ,Lefty1 *670:FAP, PAPPA, MMP3,CTHRC1 SNAI2 *28 genes and 24 genes were expressed at higher levels in soPS2 and soPS1 than NYSCF1 neuropeptide galanin, SRY, rex1 , neuronatin, NODAL, Cerberus 1 , Lefty2
Results: 5、Epigenetic reprogramming
Schematic of genome-wideSNP capture and allelotyping Use a genome-wide digital allelotyping approach to distinguish gene expression from the somatic cell-derived genome and the oocyte-derived genome in soPS cells