Open AccessNuclear Transfer‐Derived Epiblast Stem Cells Are Transcriptionally and Epigenetically Distinguishable from Their Fertilized‐Derived Counterparts
Author(s) -
Maruotti Julien,
Dai Xiang Peng,
Brochard Vincent,
Jouneau Luc,
Liu Jun,
BonnetGarnier Amélie,
Jammes Hélène,
Vallier Ludovic,
Brons I. Gabrielle M.,
Pedersen Roger,
Renard JeanPaul,
Zhou Qi,
Jouneau Alice
Publication year - 2010
Publication title -
stem cells
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.159
H-Index - 229
eISSN - 1549-4918
pISSN - 1066-5099
DOI - 10.1002/stem.400
Subject(s) - epiblast , biology , reprogramming , epigenetics , dna methylation , embryonic stem cell , induced pluripotent stem cell , genetics , stem cell , blastocyst , inner cell mass , embryo , microbiology and biotechnology , gastrulation , embryogenesis , gene , gene expression
Mouse embryonic pluripotent stem cells can be obtained from the inner cell mass at the blastocyst stage (embryonic stem cells, ESCs) or from the late epiblast of postimplantation embryos (epiblast stem cells, EpiSCs). During normal development, the transition between these two stages is marked by major epigenetic and transcriptional changes including DNA de novo methylation. These modifications represent an epigenetic mark conserved in ESCs and EpiSCs. Pluripotent ESCs derived from blastocysts generated by nuclear transfer (NT) have been shown to be correctly reprogrammed. However, NT embryos frequently undergo abnormal development. In the present study, we have examined whether pluripotent cells could be derived from the epiblast of postimplantation NT embryos and whether the reprogramming process would affect the epigenetic changes occurring at this stage, which could explain abnormal development of NT embryos. We showed that EpiSCs could be derived with the same efficiency from NT embryos and from their fertilized counterparts. However, gene expression profile analyses showed divergence between fertilized‐ and nuclear transfer‐EpiSCs with a surprising bias in the distribution of the differentially expressed genes, 30% of them being localized on chromosome 11. A majority of these genes were downregulated in NT‐EpiSCs and imprinted genes represented a significant fraction of them. Notably, analysis of the epigenetic status of a downregulated imprinted gene in NT‐EpiSCs revealed complete methylation of the two alleles. Therefore, EpiSCs derived from NT embryos appear to be incorrectly reprogrammed, indicating that abnormal epigenetic marks are imposed on cells in NT embryos during the transition from early to late epiblast. S TEM C ELLS 2010;28:743–75228:743–752