Circadian modulation of mosquito host-seeking persistence by Pigment-Dispersing Factor impacts daily biting patterns

Daily rhythms in mosquito attraction to humans are thought to drive biting patterns and contribute to disease transmission dynamics. Behavioral rhythms in many insects are controlled by specialized clock cells in the brain that are coordinated by the neuropeptide Pigment-Dispersing Factor (PDF). We show that female Aedes aegypti mosquitoes with genetically disrupted PDF display altered daily behavioral timing with reduced locomotor activity and biting in the morning. Using an automated behavioral tracking system, we also report that mosquitoes exhibit daily modulation of response persistence to the host cue carbon dioxide and loss of PDF alters this pattern. These findings indicate that PDF regulates temporal features of host-seeking behavior that promote biting success at specific times of day and may underlie blood feeding patterns observed in the field.