A5084077348- Circadian rhythm and melatonin
- Photoreceptor and optogenetics research
- Retinal Development and Disorders
- Neurobiology and Insect Physiology Research
- melanin and skin pigmentation
- Light effects on plants
- Spaceflight effects on biology
- Sleep and Wakefulness Research
- Glaucoma and retinal disorders
- Olfactory and Sensory Function Studies
- Amphibian and Reptile Biology
- Diet and metabolism studies
- Corneal Surgery and Treatments
- Impact of Light on Environment and Health
- Dietary Effects on Health
- Fish biology, ecology, and behavior
- Color Science and Applications
- Memory and Neural Mechanisms
- Animal Behavior and Reproduction
- Advanced MRI Techniques and Applications
- Nutrition, Genetics, and Disease
- bioluminescence and chemiluminescence research
- Zebrafish Biomedical Research Applications
- Skin Protection and Aging
- 3D Surveying and Cultural Heritage
University of Virginia
2010-2024
National Institute of Neurological Disorders and Stroke
2017
Neurological Surgery
2017
The University of Texas Southwestern Medical Center
2011
Uniformed Services University of the Health Sciences
1998-2007
Universidade de São Paulo
2005
Genomics Institute of the Novartis Research Foundation
2003
Scripps Research Institute
2003
Catholic University of America
1998
U.S. National Science Foundation
1995
Here we report the identification of a novel human opsin, melanopsin, that is expressed in cells mammalian inner retina. The melanopsin gene consists 10 exons and mapped to chromosome 10q22. This chromosomal localization structure differs significantly from other opsins typically have four seven exons. A survey 26 anatomical sites indicates that, humans, only eye. In situ hybridization histochemistry shows expression restricted within ganglion amacrine cell layers primate murine retinas....
We have identified an opsin, melanopsin, in photosensitive dermal melanophores of Xenopus laevis . Its deduced amino acid sequence shares greatest homology with cephalopod opsins. The predicted secondary structure melanopsin indicates the presence a long cytoplasmic tail multiple putative phosphorylation sites, suggesting that this opsin’s function may be finely regulated. Melanopsin mRNA is expressed hypothalamic sites thought to contain deep brain photoreceptors and iris, known directly...
The master circadian oscillator in the hypothalamic suprachiasmatic nucleus is entrained to day/night cycle by retinal photoreceptors. Melanopsin (Opn4), an opsin-based photopigment, a primary candidate for photoreceptor-mediated entrainment. To investigate functional role of melanopsin light resetting oscillator, we generated melanopsin-null mice (Opn4-/-). These entrain light/dark and do not exhibit any overt defect activity rhythms under constant darkness. However, they display severely...
Although mice lacking rod and cone photoreceptors are blind, they retain many eye-mediated responses to light, possibly through photosensitive retinal ganglion cells. These cells express melanopsin, a photopigment that confers this photosensitivity. Mice melanopsin still nonvisual photoreception, suggesting rods cones could operate in capacity. We observed with both outer-retinal degeneration deficiency exhibited complete loss of photoentrainment the circadian oscillator, pupillary light...
Light, including artificial light, has a range of effects on human physiology and behavior can therefore alter when inappropriately timed. One example potential light-induced disruption is the effect light circadian organization, production several hormone rhythms. Changes in light-dark exposure (e.g., by nonday occupation or transmeridian travel) shift timing system such that internal rhythms become desynchronized from both external environment internally with each other, impairing our...
Melanopsin is a novel opsin synthesized in small subset of retinal ganglion cells. Ganglion cells expressing melanopsin are capable depolarizing response to light the absence rod or cone input and thus intrinsically sensitive. convey information regarding general levels environmental illumination suprachiasmatic nucleus, intergeniculate leaflet, pretectum. Typically, communicate central visual structures by receiving from photoreceptors via bipolar amacrine Because do not require synaptic...
Melanopsin is the photopigment of intrinsically photosensitive retinal ganglion cells (ipRGCs). immunoreactivity reveals two dendritic plexuses within inner plexiform layer (IPL) and morphologically heterogeneous cells. Using enhanced immunohistochemistry, we provide a fuller description murine cell types expressing melanopsin, their contribution to melanopsin dendrites, mosaics formed by each type. M1 cells, corresponding originally described ganglion-cell photoreceptors, occupy or nuclear...
Abstract The avian retina and pineal gland contain autonomous circadian oscillators photo‐entrainment pathways, but the photopigment(s) that mediate entrainment have not been definitively identified. Melanopsin ( Opn4 ) is a novel opsin involved in of rhythms mammals. Here, we report cDNA cloning chicken melanopsin show its expression retina, brain gland. Like melanopsins identified amphibians mammals, more similar to invertebrate retinaldehyde‐based photopigments than typically found...
Non-image related responses to light, such as the synchronization of circadian rhythms day/night cycle, are mediated by classical rod/cone photoreceptors and a small subset retinal ganglion cells that intrinsically photosensitive, expressing photopigment, melanopsin. This raises possibility melanopsin may be serving conduit for photic information detected rods and/or cones. To test this idea, we developed specific immunotoxin consisting an anti-melanopsin antibody conjugated...
SUMMARY We report microspectrophotometric (MSP) data for the visual pigments and oil droplets of 17 species Caribbean anoline lizard known to live in differing photic habitats having distinctly different dewlap colors. The outgroup Polychrus marmoratus was also examined gain insight into ancestral condition. Except Anolis carolinensis, which is use vitamin A2 as its pigment chromophore, all possessed at least four vitamin-A1-based with maximum absorbance (λmax) 564, 495,455 365 nm. To...
Abstract The circadian clock in the suprachiasmatic nucleus (SCN) receives direct retinal input via retinohypothalamic tract (RHT), and ganglion cells contributing to this projection may be specialized with respect regulation of clock. However, some forming RHT bifurcate, sending axon collaterals intergeniculate leaflet (IGL) through which light has secondary access present studies provide a more extensive examination cell bifurcation evaluate whether projecting several subcortical visual...
Melanopsin is the photopigment that confers light sensitivity on intrinsically photosensitive retinal ganglion cells. Mammalian cells are involved in photic synchronization of circadian rhythms to day–night cycle. Here, we report molecular components melanopsin signaling using cultured Xenopus dermal melanophore system. Photo-activated shown initiate a phosphoinositide pathway similar found invertebrate photo-transduction. In melanophores, increases intracellular level inositol trisphosphate...
The availability of naturally occurring and transgenic retinal mutants has made the mouse an attractive experimental model to address questions regarding photoentrainment circadian rhythms. However, very little is known about cells projections nuclei murine timing system. Furthermore, effect inherited degeneration on these not understood. In this report, we have used pseudorabies virus as a neuroanatomical tract tracer in mice series questions: Which mediate responses light? What nature...
Abstract Melanopsin is the photopigment of intrinsically photosensitive retinal ganglion cells (ipRGCs). immunoreactivity reveals two dendritic plexuses within inner plexiform layer (IPL) and morphologically heterogeneous cells. Using enhanced immunohistochemistry, we provide a fuller description murine cell types expressing melanopsin, their contribution to melanopsin dendrites, mosaics formed by each type. M1 , corresponding originally described ganglion‐cell photoreceptors, occupy or...
Retinal input to the hypothalamic suprachiasmatic nucleus (SCN) synchronizes SCN circadian oscillator external day/night cycle. ganglion cells that innervate via retinohypothalamic tract are intrinsically light sensitive and express melanopsin. In this study, we provide data indicating not all SCN-projecting retinal To determine proportion of afferent melanopsin, were labeled following transsynaptic retrograde transport a recombinant Bartha strain pseudorabies virus (PRV152) constructed...