Ion channels involved in circadian and sleep control in Drosophila

NARA I. MURARO; CARINA C. COLQUE; LIA FRENKEL; FLORENCIA FERNANDEZ-CHIAPPE; ANA RICCIUTI; M FERNANDA CERIANI

Colonia del Sacramento

Congreso; XV Latin American Symposium on Chronobiology; 2019

Latin American Symposium on Chronobiology Organizing Committee

Circadian rhythms have been extensively studied in Drosophila, however, still little is known about how the electrical properties of clock neurons are specified. We have performed a behavioral genetic screen through the downregulation of candidate ion channels in the lateral ventral neurons (LNvs) and show that the hyperpolarization-activated cation current Ih is important for the behaviors that the LNvs command: temporal organization of locomotor activity and sleep. Using whole-cell patch clamp electrophysiology we demonstrate that small LNvs are bursting neurons, and that Ih is necessary to achieve the high frequency bursting firing pattern of both types of LNvs. Since firing in bursts has been associated to neuropeptide release, we hypothesized that Ih would be important for LNvs neuropeptide communication. This is indeed the case; we demonstrate that Ih is fundamental for the regulation of peptide levels and the structural remodeling of the small LNv dorsal projections.