Identification of relevant ion channels for controlling behavior in Drosophila melanogaster

CARINA C. COLQUE; MARIA FERNANDA CERIANI; NARA I. MURARO

Huerta Grande, Cordoba

Congreso; XXVIII Congreso de la Sociedad Argentina de Investigación en Neurociencias; 2013

Sociedad Argentina de Investigación en Neurociencias

Circadian rhythms (circa: around, diem: day) are biological rhythms with a period of approximately 24h and have been described in every organism on Earth. The fruit fly Drosophila melanogaster has been a biological model crucial in the development of this field. In Drosophila the small lateral ventral neurons (sLNvs) command the behavioralrhythms under free running conditions through the release of the neuropeptide PIGMENT DISPERSING FACTOR (PDF). The relationship between circadian rhythms and the function of the molecular clock in pacemaker neurons has been studied for some time. However, only recently we have started finding out about their physiological properties. The amount and type of ion channels present in the membrane of a neuron sets features such as action potential firing and excitability. In the present work we propose that the oscillation of particular voltage-gated ionic currents would establish the differential electrical properties of the LNvs between day and night, and this in turn would impact in the generation of the circadian locomotor behavior. We have performed a behavioral genetic screen through the down regulation of candidate voltage-gated ion channels using RNAinterference specifically in LNvs. In this way we have been able to identify several ion channels that affect normal circadian locomotor behavior. Further immunohistochemical analysis of the PDF circuit indicates that some ion channels might exert their effect through the modulation of PDF.