Article

Cellular Decision Making and Biological Noise: From Microbes to Mammals

Department of Systems Biology-Unit 950, The University of Texas MD Anderson Cancer Center, 7435 Fannin Street, Houston, TX 77054, USA.
Cell (Impact Factor: 32.24). 03/2011; 144(6):910-25. DOI: 10.1016/j.cell.2011.01.030
Source: PubMed

ABSTRACT

Cellular decision making is the process whereby cells assume different, functionally important and heritable fates without an associated genetic or environmental difference. Such stochastic cell fate decisions generate nongenetic cellular diversity, which may be critical for metazoan development as well as optimized microbial resource utilization and survival in a fluctuating, frequently stressful environment. Here, we review several examples of cellular decision making from viruses, bacteria, yeast, lower metazoans, and mammals, highlighting the role of regulatory network structure and molecular noise. We propose that cellular decision making is one of at least three key processes underlying development at various scales of biological organization.

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    • "Cells of a clonal population in a homogeneous medium may show large variations in size, morphology, molecular components, and activity. This cellular heterogeneity plays important functional roles in processes such as development and cell differentiation, cell decisions, virus infection, apoptosis, and cancer12345. Cell-to-cell variability is originated by differences in gene activity, which confers each cell a unique " expression fingerprint " with possible phenotypic consequences. "
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