Ecology of asynchronous asexual replication: the intraerythrocytic development cycle of Plasmodium berghei is resistant to host rhythms

Abstract

Background Daily periodicity in the diverse activities of parasites occurs across a broad taxonomic range. The rhythms exhibited by parasites are thought to be adaptations that allow parasites to cope with, or exploit, the consequences of host activities that follow daily rhythms. Malaria parasites (Plasmodium) are well-known for their synchronized cycles of replication within host red blood cells. Whilst most species of Plasmodium appear sensitive to the timing of the daily rhythms of hosts, and even vectors, some species present no detectable rhythms in blood-stage replication. Why the intraerythrocytic development cycle (IDC) of, for example Plasmodium chabaudi, is governed by host rhythms, yet seems completely independent of host rhythms in Plasmodium berghei, another rodent malaria species, is mysterious. Methods This study reports a series of five experiments probing the relationships between the asynchronous IDC schedule of P. berghei and the rhythms of hosts and vectors by manipulating host time-of-day, photoperiod and feeding rhythms. Results The results reveal that: (i) a lack coordination between host and parasite rhythms does not impose appreciable fitness costs on P. berghei; (ii) the IDC schedule of P. berghei is impervious to host rhythms, including altered photoperiod and host-feeding-related rhythms; (iii) there is weak evidence for daily rhythms in the density and activities of transmission stages; but (iv), these rhythms have little consequence for successful transmission to mosquitoes. Conclusions Overall, host rhythms do not affect the performance of P. berghei and its asynchronous IDC is resistant to the scheduling forces that underpin synchronous replication in closely related parasites. This suggests that natural variation in the IDC schedule across species represents different parasite strategies that maximize fitness. Thus, subtle differences in the ecological interactions between parasites and their hosts/vectors may select for the evolution of very different IDC schedules.

The Connotation and Realization Path of Ecological Civilization Education in Chinese Universities under the Background of Mobile Internet

“…e logical starting point of ecological civilization education is the relationship between man and nature, man and society, and man and self [15]. e content is deeper, more specific, and more scientific than environmental education and sustainable development education [16].…”

Coordination of apicoplast transcription in a malaria parasite by internal and host cues

“…Among rodent-parasitizing Plasmodium species, P. chabaudi and P. vinckei have a 24-h cycle in which they propagate synchronously, while Plasmodium berghei and Plasmodium yoelii have 18- and 21-h cycles, respectively, in which they propagate asynchronously ( 35 – 37 ). The mitotic rhythm of P. chabaudi is determined by the host rhythm, whereas that of P. vinckei is found to be partially independent of the host ( 35 ).…”

Testing the evolutionary drivers of malaria parasite rhythms and their consequences for host–parasite interactions

“…We sampled mice daily from day 3 to day 17 post infection (PI) at 0830 for the Per1/2-RF, Per1/2-AL, WT-AL and WT-DF treatments, and at 2030 for the WT-LF treatment, to ensure the age of infection (in hours) was consistent across treatments. Day-to-day dynamics are appropriate because the densities of asexuals and gametocytes vary at least an order of magnitude more across days than within a day (O'Donnell et al, 2011(O'Donnell et al, , 2021Westwood et al, 2020). Four mice were euthanised due to reaching the humane endpoints of infection (indicating they were at risk of not recovering) in the following treatments (at days PI): WT-DF (10), Per1/2-RF (8), Per1/2-AL (9, 9).…”