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bioRxiv · 10.1101/2021.09.18.460903

The synaptic basis of activity-dependent eye-specific competition

Zhang, C.·Speer, C. M.
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Abstract

Binocular vision requires proper developmental wiring of eye-specific inputs to the brain. Axons from the two eyes initially overlap in the dorsal lateral geniculate nucleus and undergo activity-dependent competition to segregate into target domains. The synaptic basis of such refinement is unknown. Here we used volumetric super-resolution imaging to measure the nanoscale molecular reorganization of developing retinogeniculate eye-specific synapses in the mouse brain. The outcome of binocular synaptic competition was determined by the relative eye-specific maturation of presynaptic vesicle content. Genetic disruption of spontaneous retinal activity prevented subsynaptic vesicle pool maturation, recruitment of vesicles to the active zone, synaptic development and eye-specific competition. These results reveal an activity-dependent presynaptic basis for axonal refinement in the mammalian visual system. One-Sentence SummarySpontaneous activity regulates the nanoscale remodeling of presynaptic terminals underlying eye-specific synaptogenesis and competition.

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Zhang, C., Speer, C. M.. 2021-09-20. The synaptic basis of activity-dependent eye-specific competition. https://doi.org/10.1101/2021.09.18.460903

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