Institute of Molecular Biotechnology of the Austrian Academy of Sciences (IMBA), Vienna BioCenter (VBC), 1030 Vienna, Austria; email:
Department of Human Genetics, Department of Biological Chemistry, and Howard Hughes Medical Institute, University of California, Los Angeles, California 90095, USA; email:
Annu Rev Genet. 2020 Nov 23;54:387-415. doi: 10.1146/annurev-genet-112618-043659. Epub 2020 Sep 4.
In life's constant battle for survival, it takes one to kill but two to conquer. Toxin-antitoxin or toxin-antidote (TA) elements are genetic dyads that cheat the laws of inheritance to guarantee their transmission to the next generation. This seemingly simple genetic arrangement-a toxin linked to its antidote-is capable of quickly spreading and persisting in natural populations. TA elements were first discovered in bacterial plasmids in the 1980s and have recently been characterized in fungi, plants, and animals, where they underlie genetic incompatibilities and sterility in crosses between wild isolates. In this review, we provide a unified view of TA elements in both prokaryotic and eukaryotic organisms and highlight their similarities and differences at the evolutionary, genetic, and molecular levels. Finally, we propose several scenarios that could explain the paradox of the evolutionary origin of TA elements and argue that these elements may be key evolutionary players and that the full scope of their roles is only beginning to be uncovered.
在生命为生存而进行的永恒斗争中，杀敌一人，制敌二人。毒素-抗毒素（TA）元件是遗传对偶体，它们欺骗遗传规律，以确保其传递给下一代。这种看似简单的遗传安排——毒素与解毒剂相连——能够快速传播并在自然种群中持续存在。TA 元件最初是在 20 世纪 80 年代在细菌质粒中发现的，最近在真菌、植物和动物中也有了特征描述，在这些生物中，它们是野生分离物杂交中遗传不相容和不育的基础。在这篇综述中，我们提供了在原核和真核生物中 TA 元件的统一观点，并强调了它们在进化、遗传和分子水平上的异同。最后，我们提出了几种可以解释 TA 元件进化起源悖论的情景，并认为这些元件可能是关键的进化参与者，而它们的全部作用才刚刚开始被揭示。
