Wiring Mechanisms for Cortical Inhibitory Circuits
2018年5月30日 16:00 - 17:00
DB Bldg. SeminarRoom A7F
Research Group Leader, Max Planck Florida Institute for Neuroscience
Cortical inhibitory interneurons (INs) play a critical role in shaping and balancing activity in neuronal networks. This indispensable task is achieved by a rich repertoire of IN subtypes, which differ in morphology, physiology, and connectivity and possess distinct functional properties. During postnatal development, cortical INs develop highly branched axonal arbors to form dense local synaptic networks and establish subtype-specific synapse specificity at cellular/subcellular levels. Despite their importance in brain function and dysfunction, wiring mechanisms for IN circuits remain largely unknown. Difficulties in dissecting IN circuit wiring are ascribed to lack of a reliable strategy to target uniform IN subtypes and follow their developmental trajectory. Chandelier cells (ChCs) powerfully control action potential generation in excitatory pyramidal neurons by specifically innervating axon initial segments. The stereotypy of axonal and synaptic organization makes ChCs an ideal experimental system to study wiring principles of IN subtypes. We have developed a genetic method that allows us to label and manipulate developing ChCs. In my talk, I will present our unpublished data demonstrating 1) that voltage-dependent calcium channels regulate axonal arborization in ChCs and 2) that cell surface molecules that are preferentially expressed in ChCs control cellular/subcellular synapse specificity. Our results provide not only deep insight into molecular mechanisms for IN circuit wiring but also novel experimental paradigms for an analysis of IN subtypes.