X-chromosome inactivation and cell memory.
Mammalian X-chromosome inactivation is an excellent example of the faithful maintenance of a determined chromosomal state. As such, it may provide insight into the mechanisms for cell memory, defined as the faithful maintenance of a determined state in clonally derived progeny cells. We review here the aspects of X-chromosome inactivation that are relevant to cell memory and discuss the various molecular mechanisms that have been proposed to explain its occurrence, with emphasis on DNA methylation and a recently proposed mechanism that depends on the timing of replication.
Riggs
A D
AD
Department of Biology, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA.
Pfeifer
G P
GP
D000818:Animals; D002454:Cell Differentiation / Q000235:genetics*; D002999:Clone Cells / Q000166:cytology; D004303:Dosage Compensation, Genetic; D004331:Drosophila melanogaster / Q000235:genetics; D005246:Feedback; D005260:Female; D005786:Gene Expression Regulation; D018392:Genomic Imprinting; D006570:Heterochromatin; D008322:Mammals / Q000235:genetics; D008745:Methylation; D008957:Models, Genetic
D006570:Heterochromatin