Project Summary
Neuronal
development.
neurons
comprised
coordinated
understand
populations
proposal,
premotor
sensor
reconstitution
their
the
of
labeled
neurons
interneurons
are
circuits arise from the activity-dependent formation and elimination of synapses during
Activity-dependent synaptic wiring has been studied extensively in peripheral sensory and motor
where the goal is o be excited or o excite. However, in the central nervous system, neural circuits are
of neurons that both excite and inhibit common targets and so activity-dependent wiring must be
during development to achieve an appropriate balance of excitation and inhibition. To better
this process, it would help to simultaneously monitor the activity of excitatory and inhibitory
and their synaptic connections to common targets during development. In this exploratory R21
we will develop a genetic strategy to monitor activity-dependent changes in excitatory and inhibitory
synaptic connectivity in the developing zebrafish spinal cord. We will use a genetically-encoded
developed in Drosophila melanogaster that uses a synaptobrevin-based GFP, YFP or CFP
across synaptic partners to simultaneously label connections in different colors and monitor
activity levels (Syb-XRASP) . In Aim 1 we will validate the CFP, YFP and GFP variants of Syb-XRASP at
neuromuscular junction of developing zebrafish. In Aim 2, we will use Syb-XRASP to monitor the assembly
connections of premotor neurons within excitatory Chx10-labeled V2a population and inhibitory En1-
V1 population. Together, these aims will allow us to assess the formation of connections rom motor
to muscles, from single V2a and V1 i nterneurons to all motor neurons, and from all V2a and V1
to single motor neurons. These experiments will provide an unprecedent view of how connections
formed during the development of circuits comprised of excitatory and inhibitory neurons.
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