das Chagas Bruna Dias, Pereira Thaís Martins, Cantanhêde Lilian Motta, da Silva Gabriela Pereira, Boité Mariana Côrtes, Pereira Luiza de Oliveira Ramos, Cupolillo Elisa
Leishmaniasis Research Laboratory, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro 21040360, Brazil.
Microorganisms. 2022 Sep 21;10(10):1883. doi: 10.3390/microorganisms10101883.
parasites present astonishing adaptative abilities that represent a matter of life or death within disparate environments during the heteroxenous parasite life cycle. From an evolutionary perspective, organisms develop methods of overcoming such challenges. Strategies that extend beyond the genetic diversity have been discussed and include variability between parasite cells during the infections of their hosts. The occurrence of subpopulation fluctuations with variable structural genomic contents demonstrates that a single strain might shelter the variability required to overcome inconsistent environments. Such intrastrain variability provides parasites with an extraordinary ability to adapt and thus survive and propagate. However, different perspectives on this evolution have been proposed. Strains or species living in the same environment can cooperate but also compete. These interactions might increase the replication rate of some parasites but cause the loss of more aggressive competitors for others. Adaptive responses to intra- and interspecific competition can evolve as a fixed strategy (replication is adapted to the average genetic complexity of infections) or an optional strategy (replication varies according to the genetic complexity of the current infection). This review highlights the complexity of interspecies and intrastrain interactions among parasites as well as the different factors that influence this interplay.
寄生虫具有惊人的适应能力，在异宿主寄生虫生命周期中，这些能力在不同环境下关乎生死存亡。从进化的角度来看，生物体发展出克服此类挑战的方法。已经讨论过的超越遗传多样性的策略包括寄生虫在感染宿主期间细胞之间的变异性。具有可变结构基因组内容的亚群波动的出现表明，单一菌株可能蕴含克服不一致环境所需的变异性。这种菌株内变异性赋予寄生虫非凡的适应能力，从而得以生存和繁殖。然而，对于这种进化提出了不同的观点。生活在同一环境中的菌株或物种既可以合作也会竞争。这些相互作用可能会提高一些寄生虫的复制率，但对其他寄生虫而言会导致更具攻击性的竞争者的损失。对种内和种间竞争的适应性反应可以演变为固定策略（复制适应感染的平均遗传复杂性）或可选策略（复制根据当前感染的遗传复杂性而变化）。这篇综述强调了寄生虫种间和菌株内相互作用的复杂性以及影响这种相互作用的不同因素。
