Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.
Curr Opin Microbiol. 2011 Apr;14(2):212-7. doi: 10.1016/j.mib.2010.12.004.
Unicellular organisms are constantly subject to sudden changes in environment. Here, we describe recent progress in understanding how epigenetic mechanisms can generate differentiation within genetically identical single cells of a clonal population. Such intrinsic phenotypic heterogeneity within a population may be considered as a bet-hedging strategy in fluctuating environments. One aspect we highlight is how transient errors in information transfer, be it errors in transcription or translation, or alternatives in protein folding, can influence the quantity and the quality of the resulting proteins, and therefore, contribute to genetic noise within individual cells. These stochastic events can provide the impetus for heritable phenotypic change in bistable epigenetic regulatory networks that are susceptible to noise and proteins capable of dominant variant conformations.
单细胞生物经常面临环境的突然变化。在这里，我们描述了在理解表观遗传机制如何在克隆群体的遗传同质单细胞内产生分化方面的最新进展。这种群体内的内在表型异质性可以被认为是在波动环境中的一种风险分散策略。我们强调的一个方面是，信息传递中的瞬时错误，无论是转录或翻译中的错误，还是蛋白质折叠的替代方式，如何影响产生的蛋白质的数量和质量，从而导致单个细胞内的遗传噪声。这些随机事件可以为对噪声敏感的双稳态表观遗传调控网络中的可遗传表型变化提供动力，这些网络中的蛋白质能够形成优势变异构象。
