Genetic dissection of cortical neuron types and circuits: from transcriptional mechanism to motor control

Inmed meeting room, Monday September 17th, 11 a.m.

Lab: Cold Spring Harbor lab., New-York

 Abstract: An enduring challenge in neuroscience is to decipher the cellular basis underlying the functional architecture of the cerebral cortex: how do vast and diverse cortical neurons across multiple cell layers and areas assemble progressively higher level organizations that confer the capacity to integrate sensory information and internal states in guiding appropriate motor action? The fundamental organization plan of the cortex is conserved across mammalian species and is ultimately encoded in the genome, which directs developmental genetic programs to assemble species-typic features such as the laminar architecture, local circuit templates, basic layout of areal networks, and the essential scaffold of cortical output pathways. Central to the developmental assembly and functional organization of cortical circuits is the generation of a large set of cardinal neuron types: the glutamatergic pyramidal neurons (PyNs) that form myriad cortical processing streams and output channels, and the GABAergic interneurons that assemble local connectivity motifs. These first principles form the basis for a genetic approach to cortical architecture through systematic dissection of neuron types. The overarching theme of my research program is to understand the principles of cortical circuit assembly and organization by integrating multi-faceted studies of neuron types in the context of cortical control of movement in the mouse. To achieve this, we combine genomic, genetic engineering, anatomical, physiological and behavioral approaches. In this talk, I will 1) summarize the status of our systematic genetic targeting of circuit elements – from subpopulations to cardinal types, 2) highlight recent discoveries on the transcriptional basis of neuron type identity, 3) discuss progress in understanding the assembly and function of a stereotyped chandelier cell–pyramidal cell circuit module, and 4) present most recent findings on distinct pyramidal neuron types in controlling skilled forelimb movement.

Contact gwendoline.bernier@inserm.fr to arrange a meeting.