Context-dependent host-symbiont interactions: shifts along the parasitism–mutualism continuum
Context-dependent host-symbiont interactions: shifts along the parasitism–mutualism continuum
复制标题
依赖于环境的宿主-共生体相互作用：沿着寄生-互惠连续体的转变
DOI：
10.1086/716635
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Duffy, Meghan
中科院分区：
文献类型：
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作者：
Rogalski, Mary Alta;Stewart Merrill, Tara;Gowler, Camden;Caceres, Carla;Duffy, Meghan
共生相互作用可以沿着互利共生-寄生连续体转变。虽然有许多研究检查通常被认为是互利共生的动力学，有时会转向寄生，但人们对从寄生到互利共生转变的潜在条件知之甚少。在湖泊种群中，我们观察到微孢子虫肠道共生体的感染有时会为其水蚤宿主带来繁殖优势，有时会带来不利。我们假设，微孢子虫可能通过减少通过肠道攻击的毒性更强的寄生虫的感染而使其宿主受益。在一项使用现场收集的动物进行的实验室研究中，我们发现有毒真菌寄生虫的孢子穿透含有微孢子虫肠道共生体的水蚤肠道的能力要差得多。我们预测，这种肠道渗透性的改变可能会对宿主健康产生不同的影响，具体取决于生态环境。现场调查数据显示，当剧毒寄生虫常见时，受微孢子虫感染的水蚤宿主具有繁殖优势，而资源稀缺导致繁殖劣势，但仅限于剧毒寄生虫相对罕见的湖泊。我们的研究结果强调了在宿主寄生虫研究中考虑多寄生虫群落背景和资源可用性的重要性，并为未来研究驱动寄生向共生梯度转变的条件打开了大门。
Symbiotic interactions can shift along a mutualism-parasitism continuum. While there are many studies examining dynamics typically considered to be mutualistic that sometimes shift toward parasitism, little is known about conditions underlying shifts from parasitism toward mutualism. In lake populations, we observed that infection by a microsporidian gut symbiont sometimes conferred a reproductive advantage and other times a disadvantage to itsDaphniahost. We hypothesized that the microsporidian might benefit its host by reducing infection by more virulent parasites, which attack via the gut. In a laboratory study using field-collected animals, we found that spores of a virulent fungal parasite were much less capable of penetrating the guts ofDaphniaharboring the microsporidian gut symbiont. We predicted that this altered gut penetrability could cause differential impacts on host fitness depending on ecological context. Field survey data revealed that microsporidian-infectedDaphniahosts experienced a reproductive advantage when virulent parasites were common while resource scarcity led to a reproductive disadvantage, but only in lakes where virulent parasites were relatively rare. Our findings highlight the importance of considering multiparasite community context and resource availability in host-parasite studies and open the door for future research into conditions driving shifts along parasitism to mutualism gradients.