Department of Animal Science, University of California, Davis, One Shields Avenue, Meyer Hall, Davis, CA 95616, USA.
J Exp Biol. 2022 Mar 8;225(Suppl_1). doi: 10.1242/jeb.243264.
Organisms mount the cellular stress response whenever environmental parameters exceed the range that is conducive to maintaining homeostasis. This response is critical for survival in emergency situations because it protects macromolecular integrity and, therefore, cell/organismal function. From an evolutionary perspective, the cellular stress response counteracts severe stress by accelerating adaptation via a process called stress-induced evolution. In this Review, we summarize five key physiological mechanisms of stress-induced evolution. Namely, these are stress-induced changes in: (1) mutation rates, (2) histone post-translational modifications, (3) DNA methylation, (4) chromoanagenesis and (5) transposable element activity. Through each of these mechanisms, organisms rapidly generate heritable phenotypes that may be adaptive, maladaptive or neutral in specific contexts. Regardless of their consequences to individual fitness, these mechanisms produce phenotypic variation at the population level. Because variation fuels natural selection, the physiological mechanisms of stress-induced evolution increase the likelihood that populations can avoid extirpation and instead adapt under the stress of new environmental conditions.
当环境参数超出有利于维持体内平衡的范围时，生物体就会启动细胞应激反应。这种反应对于在紧急情况下的生存至关重要，因为它可以保护大分子的完整性，从而维持细胞/生物体的功能。从进化的角度来看，细胞应激反应通过加速适应来对抗严重的压力，这个过程被称为应激诱导进化。在这篇综述中，我们总结了应激诱导进化的五个关键生理机制。具体来说，这些机制包括：（1）突变率的变化，（2）组蛋白翻译后的修饰，（3）DNA 甲基化，（4）染色体重组和（5）转座元件的活性。通过这些机制，生物体可以快速产生可遗传的表型，这些表型在特定环境下可能是适应性的、不适应的或中性的。无论这些机制对个体适应性的影响如何，它们都会在群体水平上产生表型变异。因为变异为自然选择提供了动力，所以应激诱导进化的生理机制增加了种群避免灭绝的可能性，而是能够在新的环境条件下适应。
