Pluripotential competence of cells associated with Nanog activity

Mech Dev. 2005 Jan;122(1):67-79. doi: 10.1016/j.mod.2004.08.008.

Abstract

Nanog is a novel pluripotential cell-specific gene that plays a crucial role in maintaining the undifferentiated state of early postimplantation embryos and embryonic stem (ES) cells. We have explored the expression pattern and function of Nanog and a Nanog-homologue, Nanog-ps1.Nanog-ps1 was mapped on Chromosome 7 and shown to be a pseudogene. Immunocytochemical analysis in vivo showed that the NANOG protein was absent in unfertilized oocytes, and was detected in cells of morula-stage embryos, the inner cell mass of blastocysts and the epiblast of E6.5 and E7.5 embryos, but not in primordial germ cells of early postimplantation embryos. In monkey and human ES cells, NANOG expression was restricted to undifferentiated cells. Furthermore, reactivation of the somatic cell-derived Nanog was tightly linked with nuclear reprogramming induced by cell hybridization with ES cells and by nuclear transplantation into enucleated oocytes. Notably, mouse Nanog (+/-) ES cells, which produced approximately half the amount of NANOG produced by wild-type ES cells, readily differentiated to multi-lineage cells in culture medium including LIF. The labile undifferentiated state was fully rescued by constitutive expression of exogenous Nanog. Thus, the activity of Nanog is tightly correlated with an undifferentiated state of cells even in nuclear reprogrammed somatic cells. Nanog may function as a key regulator for sustaining pluripotency in a dose-dependent manner.

Publication types

  • Comparative Study

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Blastocyst / metabolism*
  • Cells, Cultured
  • Chimera
  • DNA-Binding Proteins / genetics*
  • DNA-Binding Proteins / metabolism
  • Embryo, Mammalian / metabolism
  • Female
  • Haplorhini
  • Homeodomain Proteins / genetics*
  • Homeodomain Proteins / metabolism
  • Humans
  • Hybrid Cells
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Molecular Sequence Data
  • Morula / metabolism
  • Nanog Homeobox Protein
  • Pluripotent Stem Cells / cytology
  • Pluripotent Stem Cells / metabolism*
  • Pseudogenes
  • Sequence Homology, Amino Acid

Substances

  • DNA-Binding Proteins
  • Homeodomain Proteins
  • NANOG protein, human
  • Nanog Homeobox Protein
  • Nanog protein, mouse