IIBBA   05544
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE BUENOS AIRES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Ion channels that regulate neuronal physiology and circadian behavior in Drosophila melanogaster
Autor/es:
LIA FRENKEL; MARÍA FERNANDA CERIANI; CARINA C COLQUE; BRYAN HAHM ; MURARO, NARA I.; FLORENCIA FERNANDEZ
Reunión:
Congreso; SRBR 2016- Society for Research on Biological Rhythms; 2016
Institución organizadora:
SRBR
Resumen:
Circadianrhythms have been extensively studied in the fruit fly where many clock genesthat interlock through negative feedback loops and generate daily oscillationshave been described. Clock genes are expressed in approximately 150 clockneurons in the Drosophila brain.Among them, the pigment dispersing factor (PDF)-expressing lateral neurons (LNvs)have been found to play central roles as pacemaker (the small-LNvs) and arousal(the large-LNvs) neurons.Still, littleis known on how the electrical properties of Drosophila clock neurons are specified, and what mechanisms allowthem to change their firing rate on a daily basis. We have performed a behavioral genetic screenthrough the downregulation of candidate voltage-gated ion channels using RNA-interferencespecifically in LNvs. Among the positive hits we focused our attention on the hyperpolarisation-activated cation current Ih.In mammalian neurons, this channel is involved in complex neuronal behaviorssuch as bursting, the same firing pattern that LNvs display. Here, we show thatIh expression is important for the behaviors that LNvs command.Moreover, using genetics and pharmacology coupled to whole-cell patch clampelectrophysiology in ex vivo Drosophila brains, we show that Ihis necessary to achieve the high frequency bursting firing pattern of LNvs.Since bursting firing has been associated to neuropeptide release, wehypothesized that Ih would be important for PDF-mediated communication.This is indeed the case; we found that constitutive downregulation of Ihaffects sLNvs development and adult-specific downregulation of Ihaffects PDF levels and structural plasticity of sLNvs dorsal projections.