Meeting Abstract
Predation risk induces behavioral and physiological responses that have traditionally been considered acute and transitory. However, prolonged or frequent exposure to predators and their cues can impact long-term prey physiology and demographics. For instance, some moths are equipped with tympana that allow the perception of ultrasonic bat calls. Past research indicates some moths experience altered fitness and physiology after exposure to synthetic ultrasound, but the ecological relevance of these findings is not yet understood. Here, we exposed 4 adult male fall armyworm (Spodoptera frugiperda; Lepidoptera: Noctuidae) moths to either silence or sporadic recorded ultrasonic bat calls for 8 hrs and then constructed a combined de novo transcriptome based on dissected brain tissue. Using differential expression (DE) and Gene Ontology (GO) enrichment analyses, we identified 305 DE transcripts and 15 overrepresented GO terms in cue-exposed individuals. The annotated DE transcripts represented broad functional protein-coding mRNAs in the brain, including those related to neurotransmitter metabolism, ionotropic receptor expression, mitochondrial metabolism, protein chaperone activity, antioxidant activity, actin cytoskeleton dynamics, chromatin binding, epigenetic methylation, axon guidance, and neural development. The five most overrepresented GO terms included chromatin binding, macromolecular complex binding, glutamate (Glu) synthase activity, Glu metabolic process, and Glu biosynthetic process. As a first assessment of auditory predator cues on transcriptional responses in the brains of moth prey, these results suggest exposure to cues of bat presence alone can influence long-term stress physiology of ‘eared’ moth prey.