Fraser Dawn, Kaern Mads
Ottawa Institute of Systems Biology, Ottawa, Canada.
Mol Microbiol. 2009 Mar;71(6):1333-40. doi: 10.1111/j.1365-2958.2009.06605.x. Epub 2009 Feb 10.
Phenotypic diversification plays a central role in evolution and provides species with a capacity to survive environmental adversity. The profound impact of random molecular events on the shaping of life is well accepted in the context of chance mutations and genetic drift; however, the evolution of the regulatory networks encoding microorganismal stress response and survival strategies might also have been significantly influenced by gene expression noise. This likelihood has inspired numerous investigations to characterize the sources of phenotypic diversity within isogenic populations, and to explore their direct and potential biological implications. Here, we discuss different scenarios where gene expression noise might bestow a selective advantage under stress, highlighting a potentially fundamental role of stochastic mechanisms in the evolution of microbial survival strategies.
表型多样化在进化中起着核心作用，并赋予物种在环境逆境中生存的能力。在随机突变和遗传漂变的背景下，随机分子事件对生命塑造的深远影响已被广泛接受；然而，编码微生物应激反应和生存策略的调控网络的进化也可能受到基因表达噪声的显著影响。这种可能性激发了众多研究，以表征同基因群体内表型多样性的来源，并探索其直接和潜在的生物学意义。在这里，我们讨论了基因表达噪声可能在应激条件下赋予选择优势的不同情况，强调了随机机制在微生物生存策略进化中的潜在基本作用。
