Biological rhythms appear to be an elegant solution to the challenge of coordinating activities with the consequences of the Earth's daily and seasonal rotation. The genes and molecular mechanisms underpinning circadian clocks in multicellular organisms are well understood. In contrast, the regulatory mechanisms and fitness consequences of biological rhythms exhibited by parasites remain mysterious. Here, we explore how periodicity in parasite traits is generated and why daily rhythms matter for parasite fitness. We focus on malaria (Plasmodium) parasites which exhibit developmental rhythms during replication in the mammalian host's blood and in transmission to vectors. Rhythmic in-host parasite replication is responsible for eliciting inflammatory responses, the severity of disease symptoms, and fueling transmission, as well as conferring tolerance to anti-parasite drugs. Thus, understanding both how and why the timing and synchrony of parasites are connected to the daily rhythms of hosts and vectors may make treatment more effective and less toxic to hosts.

中文翻译：

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周期性寄生虫和每日宿主节律。

生物节律似乎是一种优雅的解决方案，可以很好地解决协调活动与地球日常和季节性自转的后果的挑战。支持多细胞生物生物钟的基因和分子机制已广为人知。相比之下，寄生虫表现出的生物节律的调节机制和健康后果仍然是神秘的。在这里，我们探讨了寄生虫性状的周期性是如何产生的，以及为什么每日节律对寄生虫的适应性很重要。我们专注于疟疾（疟原虫）寄生虫，这些寄生虫在哺乳动物宿主血液中复制和传播到载体的过程中表现出发育节律。有节奏的宿主内寄生虫复制负责引发炎症反应、疾病症状的严重程度和促进传播，以及赋予对抗寄生虫药物的耐受性。因此，了解寄生虫的时间和同步性如何以及为什么与宿主和媒介的日常节律相关，可能会使治疗更有效，对宿主的毒性更小。