Summary
This zebrafish study demonstrates that the phosphoinositide phosphatase Synaptojanin 1 (SynJ1) is essential for proper endolysosomal trafficking of synaptic proteins within cone photoreceptor inner segments, with deficiency leading to accumulation of vesicular structures and disrupted autophagy. Notably, these pathological changes are exacerbated by prolonged darkness, suggesting that light exposure conditions may influence retinal cellular health at a molecular level.
Key Findings
- Loss of SynJ1 in zebrafish nrc(a14) mutants causes accumulation of RibeyeB and VAMP2/synaptobrevin synaptic proteins in cone inner segments rather than synapses.
- Large vesicular structures and enlarged acidic vesicles accumulate in nrc(a14) cone inner segments, with disruption particularly pronounced after prolonged dark incubation.
- Autophagy disruption in cone photoreceptors is exacerbated by darkness, indicating a light-dependent component to endolysosomal trafficking maintenance.
- Outer segments and connecting cilia of mutant cones appear structurally normal, isolating the trafficking defect to inner segment endolysosomal pathways.
Categories
Eye Health & Vision: Investigates photoreceptor biology and intracellular trafficking defects in cone photoreceptors relevant to retinal health.
The Science of Light: Examines how light-dark cycles affect intracellular vesicle accumulation and autophagy disruption in cone photoreceptors.
Author(s)
K Attia
Publication Year
2023
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