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bioRxiv · 10.1101/2025.06.02.657513

Title: Retinal Calcium Waves Coordinate Uniform Tissue Patterning of the Drosophila Eye.

Choi, B. J.·Chen, Y.-C.·Desplan, C.
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Abstract

Optimal neural processing relies on precise tissue patterning across diverse cell types. Here, we show that spontaneous calcium waves arise among non-neuronal support cells in the developing Drosophila eye to drive retinal morphogenesis. These waves are initiated by Cad96Ca receptor tyrosine kinase signaling, triggering PLC{gamma}-mediated calcium release from the endoplasmic reticulum. A cell-type-specific Innexin code coordinates wave propagation through a defined gap junction network among non-neuronal retinal cells, excluding photoreceptors. Wave intensity scales with ommatidial size, triggering stronger Myosin II-driven apical contraction at interommatidial boundaries in larger ommatidia. This size-dependent mechanism compensates for early boundary irregularities, ensuring uniform ommatidial packing critical for precise optical architecture. Our findings reveal how synchronized calcium signaling among non-neuronal cells orchestrates tissue patterning in the developing nervous system.

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Choi, B. J., Chen, Y.-C., Desplan, C.. 2025-06-03. Title: Retinal Calcium Waves Coordinate Uniform Tissue Patterning of the Drosophila Eye.. https://doi.org/10.1101/2025.06.02.657513

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