Article

Integrating Physiological Regulation with Stem Cell and Tissue Homeostasis

Howard Hughes Medical Institute, Life Sciences Institute, Department of Internal Medicine, and Center for Stem Cell Biology, University of Michigan, Ann Arbor, MI 48109-2216, USA.
Neuron (Impact Factor: 15.98). 05/2011; 70(4):703-18. DOI: 10.1016/j.neuron.2011.05.011
Source: PubMed

ABSTRACT Stem cells are uniquely able to self-renew, to undergo multilineage differentiation, and to persist throughout life in a number of tissues. Stem cells are regulated by a combination of shared and tissue-specific mechanisms and are distinguished from restricted progenitors by differences in transcriptional and epigenetic regulation. Emerging evidence suggests that other aspects of cellular physiology, including mitosis, signal transduction, and metabolic regulation, also differ between stem cells and their progeny. These differences may allow stem cells to be regulated independently of differentiated cells in response to circadian rhythms, changes in metabolism, diet, exercise, mating, aging, infection, and disease. This allows stem cells to sustain homeostasis or to remodel relevant tissues in response to physiological change. Stem cells are therefore not only regulated by short-range signals that maintain homeostasis within their tissue of origin, but also by long-range signals that integrate stem cell function with systemic physiology.

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