Year: 2026
Type: preprint
Abstract: Opsins are light-activated receptors. A basic question is how the molecular properties of an opsin shape its effects on the organism. In mammals, melanopsin regulates perception, cognition, physiology, and mood. Because these actions are vital, an international standard has been formulated to express light in terms of melanopsin stimulation. Short wavelengths are absorbed best by melanopsin and should drive its effects most strongly. We report that melanopsin's cellular and behavioral effects show little or even opposite wavelength sensitivity in some regimes. This divergence stems from melanopsin's persistent activity, which generates adaptation. Wavelengths absorbed strongly by melanopsin produce high persistent activity and adaptation, giving net desensitization, whereas wavelengths absorbed weakly can produce sensitization instead. We provide a quantitative model that captures these transformations. This work indicates how the downstream actions of a molecule may diverge starkly from its intrinsic properties.
Institutions: Boston Children's Hospital, Harvard University, Emory University
Language: English
Subfield: Endocrine and Autonomic Systems
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
Funders: National Science Foundation, March of Dimes Foundation, Brigham and Women's Hospital, Harvard University, Ögonfonden, Broad Institute, National Institutes of Health, Intellectual and Developmental Disabilities Research Center, National Heart, Lung, and Blood Institute, National Eye Institute, Alcon Research Institute, Eunice Kennedy Shriver National Institute of Child Health and Human Development
Awards: Physiological Mechanisms of Intensity Encoding in Ganglion Cell Photoreceptors, Subcellular Origins of Extensive Spatial Integration by Ganglion Cell Photoreceptors, G3916677169, G4550073829, Origins and Transformations of Signals for Circadian Regulation, Boston Intellectual and Developmental Disabilities Research Center, G7463335965, Properties and Mechanisms of Melanopsin Photoreception, Transformations of photic information in melanopsin pathways, Signal Generation and Processing in the Retinohypothalamic Pathway, Downstream Actions of Biophysical Mechanisms in the Visual System, CORE GRANT FOR VISION RESEARCH, Training in Sleep, Circadian, and Respiratory Neurobiology, Intrinsically photosensitive retinal ganglion cells and their central projections
OpenAlex ID: W7213342528