In search of the mechanisms that govern pluripotency and embryonic stem cell (ESC) self-renewal, a growing list of evidence highlights chromatin as a leading factor, controlling ESC maintenance and differentiation. In-depth investigation of chromatin in ESCs revealed distinct features, including DNA methylation, histone modifications, chromatin protein composition and nuclear architecture. Here we review recent literature describing different aspects of chromatin and genome organization in ESCs. The emerging theme seems to support a mechanism maintaining chromatin plasticity in ESCs but without any dramatic changes in the organization and nuclear positioning of chromosomes and gene loci themselves. Plasticity thus seems to be supported more by different mechanisms maintaining an open chromatin state and less by regulating the location of genomic regions.
Bibliographical noteFunding Information:
EM is a Joseph H. and Belle R. Braun Senior Lecturer in Life Sciences and is supported by the Israel Science Foundation (ISF 215/07 and 943/09), the Israel Ministry of Health (6007) the European Union (IRG-206872) and an Alon Fellowship. AM is supported by the Israel Cancer Research Foundation (ICRF).