Differential gene expression in Acromyrmex leaf-cutting ants after challenges with two fungal pathogens

Social insects in general and leaf-cutting ants in particular have increased selection pressures on their innate immune system due to their social lifestyle and monoclonality of the symbiotic fungal cultivar. As this symbiosis is obligate for both parties, prophylactic behavioural defences against infections are expected to increase either ant survival or fungus-garden survival, but also to possibly trade off when specific infections differ in potential danger. We examined the effectiveness of prophylactic behaviours and modulations of innate immune defences by a combination of inoculation bioassays and genome-wide transcriptomic studies (RNA-Seq), using an ant pathogen (Metarhizium brunneum) and a fungus-garden pathogen (Escovopsis weberi) and administering inoculations both directly and indirectly (via the symbiotic partner). Upon detection of pathogen conidia, ant workers responded by increasing both general activity and the frequency of specific defence behaviours (self-grooming, al...总体而言，社会性昆虫，尤其是切叶蚁，由于其群居生活方式以及共生真菌栽培物的单克隆性，其先天免疫系统（innate immune system）承受了更强的选择压力。鉴于这种专性共生关系对双方均为必需，针对感染的预防性行为防御理应提升蚂蚁或真菌菌圃的存活率，但当不同感染的潜在危害存在差异时，这类防御也可能存在权衡效应。本研究通过接种生物测定与全基因组转录组学研究（RNA-Seq）相结合的方法，以蚂蚁病原菌（布鲁尼亚绿僵菌，Metarhizium brunneum）和真菌菌圃病原菌（Escovopsis weberi）为研究对象，分别通过直接接种和间接接种（经由共生伙伴）的方式进行处理，以此探究预防性行为及先天免疫防御调控的有效性。当检测到病原菌分生孢子后，工蚁会通过提升整体活动水平与特定防御行为（自我理毛、al...