Lecture: Tibor Harkany

The Linda & Jack Gill Center for Biomolecular Science and The Program in Neuroscience are pleased to present the following:

Tibor Harkany, Ph.D., University of Aberdeen School of Medical Sciences and The Karolinska Institutet, will present, "Endocannabinoid signaling during brain development."

Wednesday, April 15, 2009
4:00 p.m.
Psychological and Brain Sciences, Room PY101

Abstract:
Endocannabinoids (eCB) function as retrograde messengers at both excitatory and inhibitory synapses, and control various forms of synaptic plasticity in the adult brain. The molecular machinery required for specific eCB functions during maintenance of synaptic homeostasis is becoming well established. However, eCB signaling plays surprisingly fundamental roles in controlling the acquisition of neuronal identity during CNS development. Recent work suggests that selective recruitment of regulatory signaling networks to CB1 cannabinoid receptors dictates neuronal state-change decisions. In addition, the spatial localization and temporal precision of eCB action emerges as a novel organizer in developing neuronal networks. At the moment, we are far from understanding the molecular logic and chronodynamics of how eCB signaling networks specify in the embryonic brain, and how their specific neurodevelopmental functions relate to and define their retrograde control of neurotransmitter release at mature synapses. Important open questions include: where and when eCBs are produced in the developing brain; the molecular identity of eCBs and whether they represent ‘active’ signals; whether respective receptors and intracellular signal transduction cascades differ from those in the postnatal brain; how eCB signaling integrates with other regulatory systems; and how the relative power of this newly-emerging signaling entity contributes to define neurodevelopmental processes. In this talk, I will summarize contemporary discoveries establishing eCB-driven cellular identification events in the developing cerebrum, and define a unifying concept of how eCB signaling provides positional signals for excitatory and inhibitory afferents along the dendritic tree of cortical neurons, thus shaping the complexity of cortical connectivity.