Trade-offs in the evolution of virulence in an indirectly transmitted macroparasite
Trade-offs in the evolution of virulence in an indirectly transmitted macroparasite
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DOI：
10.1098/rspb.2000.1367
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发表时间：
2001-02-07
影响因子：
4.7
通讯作者：
Woolhouse, MEJ
中科院分区：
文献类型：
--
作者：
Davies, CM;Webster, JP;Woolhouse, MEJ
寄生虫毒力进化和维持的适应性权衡理论要求毒力与寄生虫的其他适应度特征在遗传上相关。许多理论模型依赖于石油毒力和传播力之间的正相关关系.他们假设，高寄生虫复制率与传播的可能性高有关(因此，寄生虫适合度增加)，但也与对宿主的高水平损害(高毒力)有关。血吸虫是一种大型寄生虫，具有间接的生命周期，涉及哺乳动物和软体动物宿主。在这里，我们通过五个亚株的发展，证明了血吸虫毒力的遗传基础。我们进一步使用了这些亚株。以调查是否存在与毒力遗传相关的寄生虫适应性特征。正如预测的那样，(小鼠)最终宿主的高毒力与寄生虫的复制呈正相关。相反，在(蜗牛)中间宿主中，高毒力与低寄生虫复制率相关。对最终宿主的感染力和寄生虫复制的变化被认为是维持钉螺宿主毒力的一种补偿机制。这是首次报道在间接传播的大型寄生虫中，寄生虫在不同宿主之间繁殖成功的权衡。
The adaptive trade-off theory for the evolution and maintenance of parasite virulence requires that virulence be genetically correlated with other fitness characteristics of the parasite. Many theoretical models rely oil a positive correlation between virulence and transmissibility. They assume that high parasite replication rates are associated with a high probability of transmission land, hence, increased parasite fitness), but also with high levels of damage to the host (high virulence). Schistosomes are macroparasites with an indirect life cycle involving a mammalian and a molluscan host. Here we demonstrate, through the development of five substrains, a genetic basis for schistosome virulence. We used these substrains further. in order to investigate the presence of parasite fitness traits that were genetically correlated with virulence. High Virulence in the (mouse) definitive host was, as predicted, positively correlated with parasite replication. In contrast, in the (snail) intermediate host high virulence was associated with low parasite replication rates. Variation in infectivity to and parasite replication in the definitive host was suggested as a compensating mechanism for the maintenance of virulence in the snail host. This is the first report of a trade-off in parasite reproductive success across hosts in an indirectly transmitted macroparasite.