H3.3 replacement facilitates epigenetic reprogramming of donor nuclei in somatic cell nuclear transfer embryos Review uri icon


MeSH Major

  • Cellular Reprogramming
  • Chromatin Assembly and Disassembly
  • Epigenesis, Genetic
  • Histones


  • Transfer of a somatic nucleus into an enucleated oocyte is the most efficient approach for somatic cell reprogramming. While this process is known to involve extensive chromatin remodeling of the donor nucleus, the maternal factors responsible and the underlying chromatin-based mechanisms remain largely unknown. Here we discuss our recent findings demonstrating that the histone variant H3.3 plays an essential role in reprogramming and is required for reactivation of key pluripotency genes in somatic cell nuclear transfer (SCNT) embryos. Maternal-derived H3.3 replaces H3 in the donor nucleus shortly after oocyte activation, with the amount of replacement directly related to the differentiation status of the donor nucleus in SCNT embryos. We provide additional evidence to suggest that de novo synthesized H3.3 replaces histone H3 carrying repressive modifications in the donor nuclei of SCNT embryos, and hypothesize that replacement may occur at specific loci that must be reprogrammed for gene reactivation.

publication date

  • August 25, 2014



  • Review



  • eng

Digital Object Identifier (DOI)

  • 10.4161/nucl.36231

PubMed ID

  • 25482190

Additional Document Info

start page

  • 369

end page

  • 75


  • 5


  • 5