Summary
This study provides the first direct characterization of human melanopsin photopigment, finding peak spectral sensitivity at 479 nm (blue-cyan light) and confirming coupling to both Gq and Gi/o G-protein pathways. These findings validate the use of rodent models for melanopsin research and support lighting design strategies that target ~480 nm wavelengths to maximize or minimize ipRGC-driven circadian and alerting responses.
Key Findings
- Human melanopsin peak spectral sensitivity: 479 nm, consistent with a vitamin A1-based opsin pigment
- Light activation of human melanopsin induces a high-amplitude increase in intracellular calcium and a modest reduction in cAMP, indicating coupling to both Gq and Gi/o G-protein classes
- Human melanopsin G-protein selectivity and spectral sensitivity are similar to rodent melanopsin, supporting translational validity of mouse models
- Chicken Opn4m and Opn4x showed additional Gs activity not observed in human or mouse melanopsin
Categories
The Science of Light: Directly characterizes human melanopsin spectral sensitivity (peak 479 nm) and G-protein coupling, foundational for circadian lighting design standards.
Author(s)
HJ Bailes, RJ Lucas
Publication Year
2013
Number of Citations
1
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