Talk abstracts
Talk on Tuesday 11:35-11:55am submitted by Jason Wester
How does the brain wire itself during development?
Jason Wester (Neuroscience)
Abstract:
The nervous system contains many different types of neurons and the synaptic connections they make to form circuits are not random. Neurons choose their synaptic partners and form connections with unique physiological properties based on their own identity and that of their target. Here, I describe recent progress from our lab to understand the molecular mechanisms that determine neuronal identity and circuit formation in the hippocampus. The hippocampus is a brain structure necessary for learning and memory but how it accomplishes these functions remains unclear. Recent work found that hippocampal excitatory neurons can be split into two subtypes that receive different levels of inhibitory input from local interneurons. This differentially gates how strongly each subtype responds to an input, even if it comes from the same source. This suggests that neighboring pyramidal neurons may be engaged in processing unique, parallel streams of information. Using molecular genetic techniques available in mice, we found that the transcriptional regulator Satb2 controls pyramidal cell identity and inhibitory synapse formation. We show that knocking this gene out from pyramidal neurons during early development equalizes the level of inhibition the two subtypes receive. Thus, we identified a fundamental developmental mechanism that determines pyramidal identity and hippocampal circuit organization.
Keywords: neural development, synapses, hippocampus