Dormivigilia

Today, we had our last seminar of the coordinated Biological Sciences and Psychology faculty search, and it was awesome. Dr. Bridget Lear from Northwestern presented to us the molecular machinery involved with the regulation of Drosophila clock output (i.e. locomotor activity). Because the entire genome of Drosophila has been sequenced and is publicly available, Bridget has access to several molecular tools to localize the expression of genes and related molecular components within the Drosophila nervous system, and can subsequently manipulate these constituents to determine their influences on behavioral clock output. Specifically, she focuses on genes that mediate circadian locomotor activity, which under standard light:dark conditions is crepuscular (activity is distributed near dusk and dawn). By deleting particular genes, such as ether-a-go-go (second best gene name next to sonic hedgehog) and narrow abdomen , which additionally result in phenotypic body morphologies, the flies become arrythmic, in that they no longer have organized locomotor activity near lights-on (dawn) and lights-off (dusk), but rather have intermittent, sporadic activity across random hours of the 24 hour day. Bridget additionally explores the kinetics of ion channels associated with these genes and subsequent effects on behavorial clock output. Her research and molecular techniques used in such a simplistic, yet valuable model can hopefully provide insight into the cellular and molecular perturbations that drive circadian rhythm disorders and other disorders/diseases, such as cardiovascular disease, metabolic disorders, mood disorders, and even cancer, that are sometimes co-morbid with these circadian rhythm disorders.

Lear, B., Lin, J., Keath, J., McGill, J., Raman, I., & Allada, R. (2005). The Ion Channel Narrow Abdomen Is Critical for Neural Output of the Drosophila Circadian Pacemaker Neuron, 48 (6), 965-976 DOI: 10.1016/j.neuron.2005.10.030