Cross-regulation of the Nanog and Cdx2 promoters

The first cell fate choice in the mammalian embryo, the segregation of the inner cell mass (ICM) and trophectoderm (TE), is regulated by the mutually antagonistic effects of the transcription factors, Oct4 and Cdx2, while the pluripotency factor, Nanog, is essential to specify the epiblast. We have analyzed the promoters of Nanog and Cdx2, and have found that these two transcription factors are likewise regulated reciprocally. Using an embryonic stem cell line with conditional TE differentiation, we show that Nanog overexpression suppresses the upregulation of TE markers, while Nanog knockdown upregulates the expression of TE markers. We further show that Nanog and Cdx2 bind to and repress each other's promoters. However, whereas Nanog knockout results in detectable Cdx2 expression in the ICM, we observe no overt disruption of blastocyst development, indicating that Nanog plays a subservient role to Oct4 in segregation of the ICM and TE.

[1]  Janet Rossant,et al.  Cdx2 is required for correct cell fate specification and differentiation of trophectoderm in the mouse blastocyst , 2005, Development.

[2]  Radu Dobrin,et al.  Dissecting self-renewal in stem cells with RNA interference , 2006, Nature.

[3]  G. Daley,et al.  HoxB4 Confers Definitive Lymphoid-Myeloid Engraftment Potential on Embryonic Stem Cell and Yolk Sac Hematopoietic Progenitors , 2002, Cell.

[4]  X. Chen,et al.  The Oct4 and Nanog transcription network regulates pluripotency in mouse embryonic stem cells , 2006, Nature Genetics.

[5]  J. Nichols,et al.  Functional Expression Cloning of Nanog, a Pluripotency Sustaining Factor in Embryonic Stem Cells , 2003, Cell.

[6]  L. Hyslop,et al.  Downregulation of NANOG Induces Differentiation of Human Embryonic Stem Cells to Extraembryonic Lineages , 2005, Stem cells.

[7]  M. Murakami,et al.  The Homeoprotein Nanog Is Required for Maintenance of Pluripotency in Mouse Epiblast and ES Cells , 2003, Cell.

[8]  J. Rossant,et al.  Genetic regulation of stem cell origins in the mouse embryo , 2005, Clinical genetics.

[9]  G. Martin,et al.  Isolation of a pluripotent cell line from early mouse embryos cultured in medium conditioned by teratocarcinoma stem cells. , 1981, Proceedings of the National Academy of Sciences of the United States of America.

[10]  H. Schöler,et al.  Formation of Pluripotent Stem Cells in the Mammalian Embryo Depends on the POU Transcription Factor Oct4 , 1998, Cell.

[11]  G. Daley,et al.  Inducible transgene expression in mouse stem cells. , 2005, Methods in molecular medicine.

[12]  J. Rossant,et al.  Promotion of trophoblast stem cell proliferation by FGF4. , 1998, Science.

[13]  G. Daley,et al.  Ras-MAPK signaling promotes trophectoderm formation from embryonic stem cells and mouse embryos , 2008, Nature Genetics.

[14]  J. Rossant,et al.  Embryonic stem cells alone are able to support fetal development in the mouse. , 1990, Development.

[15]  Megan F. Cole,et al.  Core Transcriptional Regulatory Circuitry in Human Embryonic Stem Cells , 2005, Cell.

[16]  G. Pan,et al.  A negative feedback loop of transcription factors that controls stem cell pluripotency and self‐renewal , 2006, FASEB journal : official publication of the Federation of American Societies for Experimental Biology.

[17]  J. Miyazaki,et al.  Quantitative expression of Oct-3/4 defines differentiation, dedifferentiation or self-renewal of ES cells , 2000, Nature Genetics.

[18]  J. Utikal,et al.  Directly reprogrammed fibroblasts show global epigenetic remodeling and widespread tissue contribution. , 2007, Cell stem cell.

[19]  S. Cawley,et al.  Unbiased Mapping of Transcription Factor Binding Sites along Human Chromosomes 21 and 22 Points to Widespread Regulation of Noncoding RNAs , 2004, Cell.

[20]  Janet Rossant,et al.  Interaction between Oct3/4 and Cdx2 Determines Trophectoderm Differentiation , 2005, Cell.

[21]  S. Orkin,et al.  Site-directed, virus-free, and inducible RNAi in embryonic stem cells , 2007, Proceedings of the National Academy of Sciences.

[22]  M. Kaufman,et al.  Establishment in culture of pluripotential cells from mouse embryos , 1981, Nature.

[23]  P. J. Welch,et al.  Differentiation of Mouse Embryonic Stem Cells after RNA Interference‐Mediated Silencing of OCT4 and Nanog , 2006, Stem cells.