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bioRxiv · 10.1101/2023.02.13.527055

Neurexin 3 is required for the specific S-cone to S-cone bipolar cell synapse in the mammalian retina

Kunze, V. P.·Angueyra, J.·Ball, J. M.·Thomsen, M. B.·Li, X.·Sabnis, A.·Nadal-Nicolas, F. M.·Li, W.
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Abstract

Precise wiring within sensory systems is critical for the accurate transmission of information. In the visual system, S-cone photoreceptors specialize in detecting short-wavelength light, crucial to color perception and environmental cue detection. S-cones form specific synapses with S-cone bipolar cells (SCBCs), a connection that is remarkably consistent across species. Yet, the molecular mechanisms guiding this specificity remain unexplored. To address this, we used the cone-dominant ground squirrel for deep-sequencing of cone subtype transcriptomes and identified Nrxn3 as an essential molecule for the S-cone to SCBC synapse. Using transgenic mouse models, we further examined the role of Nrxn3 in S-cones and discovered a significant reduction of SCBC connections in the absence of Nrxn3. This finding extends the known functions of neurexins, typically associated with synapse regulation, by highlighting their essential role in a specific synaptic connection for the first time. Moreover, the differentially expressed genes identified here pave the way for further investigations into the unique functions of cone subtypes.

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Kunze, V. P., Angueyra, J., Ball, J. M., Thomsen, M. B., Li, X., Sabnis, A., Nadal-Nicolas, F. M., Li, W.. 2023-02-14. Neurexin 3 is required for the specific S-cone to S-cone bipolar cell synapse in the mammalian retina. https://doi.org/10.1101/2023.02.13.527055

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