title: Epigenetic stability of repressed states involving the histone variant macroH2A revealed by nuclear transfer to Xenopus oocytes.
abstract: How various epigenetic mechanisms restrict chromatin plasticity to determine the stability of repressed genes is poorly understood. Nuclear transfer to Xenopus oocytes induces the transcriptional reactivation of previously silenced genes. Recent work suggests that it can be used to analyze the epigenetic stability of repressed states. The notion that the epigenetic state of genes is an important determinant of the efficiency of nuclear reprogramming is supported by the differential reprogramming of given genes from different starting epigenetic configurations. After nuclear transfer, transcription from the inactive X chromosome of post-implantation-derived epiblast stem cells is reactivated. However, the same chromosome is resistant to reactivation when embryonic fibroblasts are used. Here, we discuss different kinds of evidence that link the histone variant macroH2A to the increased stability of repressed states. We focus on developmentally regulated X chromosome inactivation and repression of autosomal pluripotency genes, where macroH2A may help maintain the long-term stability of the differentiated state of somatic cells.
authors: Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, UK. v.pasque@gurdon.cam.ac.uk
authors: Vincent
authors: V
authors: Pasque
authors: Richard P
authors: RP
authors: Halley-Stott
authors: Astrid
authors: A
authors: Gillich
authors: Nigel
authors: N
authors: Garrett
authors: John B
authors: JB
authors: Gurdon
mesh_terms: D000818:Animals; D004625:Embryo, Nonmammalian / Q000166:cytology / Q000378:metabolism; D044127:Epigenesis, Genetic / Q000502:physiology*; D006657:Histones / Q000235:genetics / Q000378:metabolism*; D053652:Nuclear Transfer Techniques; D009865:Oocytes / Q000166:cytology / Q000378:metabolism*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000502:physiology; D014960:X Chromosome / Q000235:genetics / Q000378:metabolism; D029867:Xenopus Proteins / Q000235:genetics / Q000378:metabolism*; D014982:Xenopus laevis
chemical_list: D006657:Histones; D012097:Repressor Proteins; D029867:Xenopus Proteins; C120756:macroH2A histone