Xist function: bridging chromatin and stem cells.
In mammals, dosage compensation is achieved by transcriptional silencing of one of the two female X chromosomes. X inactivation is dynamically regulated in development. The non-coding Xist RNA localizes to the inactive X, initiates gene repression in the early embryo, and later stabilizes the inactive state. Different functions of Xist are observed depending on which epigenetic regulatory pathways are active in a given cell. Because Xist has evolved recently, with the origin of placental mammals, the underlying pathways are also important in regulating developmental control genes. This review emphasizes the opportunity that Xist provides to functionally define epigenetic transitions in development, to understand cell identity, pluripotency and stem cell differentiation.
Wutz
Anton
A
Research Institute of Molecular Pathology, Dr. Bohr-Gasse 7, 1030 Vienna, Austria. wutz@imp.univie.ac.at
D000818:Animals; D002454:Cell Differentiation; D002843:Chromatin / Q000378:metabolism / Q000502:physiology*; D044127:Epigenesis, Genetic / Q000502:physiology; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D006801:Humans; D008954:Models, Biological; D063146:Polycomb-Group Proteins; D011485:Protein Binding; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated / Q000235:genetics / Q000502:physiology*; D012097:Repressor Proteins / Q000378:metabolism / Q000502:physiology; D013234:Stem Cells / Q000166:cytology*; D049951:X Chromosome Inactivation / Q000502:physiology
D002843:Chromatin; D063146:Polycomb-Group Proteins; D062085:RNA, Long Noncoding; D022661:RNA, Untranslated; D012097:Repressor Proteins; C077885:XIST non-coding RNA