IIBBA   05544
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE BUENOS AIRES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
The axon-guidance roundabout gene affects the communication in the circadian network.
Autor/es:
JIMENA BERNI; ESTEBAN BECKWITH; MARÍA PAZ FERNÁNDEZ; EZEQUIEL ARANOVICH; MARÍA FERNANDA CERIANI
Lugar:
Sandestin, Florida, USA
Reunión:
Taller; XI meeting Society for Biological Rhythms Research; 2008
Institución organizadora:
Society for Biological Rhythms Research
Resumen:
Great efforts have been directed to the dissection of the cell-autonomous circadian oscillator in Drosophila. However, less information is available regarding how this oscillator controls rhythmic rest–activity cycles. We have identified a viable allele of roundabout, robohy, where the period of locomotor activity is shortened. From its role in axon pathfinding we anticipated developmental defects in circadian structures; however robohy produced minor defects in the architecture of the circuits essential for rhythmic behavior. The observation that ROBO is detected in the circadian network, coupled to its effect on rhythmicity when downregulated specifically within the PDF circuit in the adult  strengthened the possibility of a novel role for ROBO at this postdevelopmental stage. Genetic interactions between pdf01 and robohy suggest that ROBO could alter the communication within different clusters of the circadian network, thus impinging on two basic properties, periodicity and ⁄ or rhythmicity. In particular, introducing a copy of robohy into pdf01 gave rise to over 80% rhythmic individuals and also rescued the morning anticipation, suggesting that PDF-independent factors could modulate this circadian behavior. Early translocation of PERIOD to the nucleus in robohy pacemaker cells were first detected in adult flies indicating that robohy could only affect the molecular oscillations when the adult circadian network is functional. We propose that distorted neuronal activity caused by defective synaptic contacts in any component of the circadian network could in turn impinge upon the molecular oscillations in the small LNvs.