Paul Taghert

Washington University Medical School

Mechanisms of Neuropeptide Synchronization in Drosophila Circadian Neural Circuits

Monday 09 June 2014

Location: Centre for Neural Circuits and Behaviour, Tinsley Building, Mansfield Road, Oxford

Abstract: Neuronal Development:  We ask how Neuroendocrine Neurons acquire their highly specialized cellular properties.  These are secretory cells that produce process transport store diverse bioactive peptides.  They release them in large amounts upon receiving proper signals (regulated secretion).  Using Drosophila genetics we have discovered the DIMM transcription factor as a critical component in the mechanism underlying such cellular specialization.  DIMM is an example of a regulatory molecular serving as a Scaling Factor to enhance differentiation by quantitative biasing of cellular properties.  Our current efforts focus on the We are defining all DIMM molecular targets, to learn how DIMM is controlled by cell-cell signaling and to explore DIMM roles in evolution (current studies focus on honey bees).

Circadian Neurobiology:  We study the physiology of neuronal circuits that underlie circadian clock control of locomotor rhythms. In the fly brain ~150 neurons are dedicated circadian pacemakers and have demonstrable roles in promoting daily rhythmic behavior.  The neuropeptide PDF is an important signal released by ~10% of these neurons and is related to mammalian VIP in this functional capacity.  Currently we pursue questions related to: (i) the signaling pathways controlled PDF to modulate the clock activity of pacemaker neurons; (ii) measuring the physiological activity of the entire network (using calcium and cAMP reporters) in real-time over 1 to many days.  Relating clock properties to the neuronal properties of pacemaker cells is a challenging and important goal for this work.