ABSTRACT
Pluripotent stem cells are defi ned by two criteria, the ability to undergo self-renewal and multi-lineage differentiation. The maintenance of stem cell self-renewal is based on the rapid progression through the cell cycle, placing cell cycle regulation as a central component of stem cell maintainence. Interestingly, pluripotent stem cells have many unique cell cycle characteristics that distinguish them from somatic cells. Most notable of these is the unique structure of their cell cycle profi le. Unlike somatic stem and differentiated cells, pluripotent stem cells possess a short G1phase and have an unusually large percentage of cells in S phase. The regulatory mechanisms that promote this unique cell cycle profi le are described, along with the potential purpose of having this cell cycle structure and what it may mean for maintaining pluripotency and self-renewal. Importantly, the mechanisms that regulate the cell cycle of mouse pluripotent stem cells is broadly different from somatic or differentiated cells, and also appear
Department of Biochemistry and Molecular Biology, Paul D. Coverdell Center for Biomedical and Health Sciences, The University of Georgia, 500 D.W. Brooks Drive, Athens, GA 30602, USA. *Corresponding author: sdalton@uga.edu
List of abbreviations after the text.
