CRYPTOCHROME mediates behavioral executive choice in response to UV light

Significance Many animals exhibit behavioral responses to UV light, including harmful insects. Recently, the explosive spread of diseases carried by mosquitoes has increased motivation to better understand insect UV phototransduction. CRYPTOCHROME (CRY) is a highly conserved nonopsin photoreceptor expressed in a small number of brain circadian and arousal neurons in Drosophila melanogaster that mediates cell-autonomous electrophysiological membrane excitability in response to UV light. CRY signaling modulates multiple fly behaviors evoked by UV light, including acute nighttime arousal responses to light flashes and phototaxis toward low-intensity UV light. Loss of CRY or the redox sensor HYPERKINETIC (HK) leads to the loss of ability to avoid high-intensity UV light; thus, CRY signaling exhibits novel features of behavioral executive choice.