Melanopsin Phototransduction Is Repurposed by ipRGC Subtypes to Shape the Function of Distinct Visual Circuits

Neuron, Год журнала: 2018, Номер 99(4), С. 754 - 767.e4

Опубликована: Июль 14, 2018

Язык: Английский

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Circadian Photoentrainment in Mice and Humans

Biology, Год журнала: 2020, Номер 9(7), С. 180 - 180

Опубликована: Июль 21, 2020

Light around twilight provides the primary entrainment signal for circadian rhythms. Here we review mechanisms and responses of mouse human systems to light. Both utilize a network photosensitive retinal ganglion cells (pRGCs) expressing photopigment melanopsin (OPN4). In both species action spectra functional expression OPN4 in vitro show that has λmax close 480 nm. Anatomical findings demonstrate there are multiple pRGC sub-types, with some evidence mice, but little humans, regarding their roles regulating physiology behavior. Studies non-human primates rods cones project can modulate light pRGCs. Such an integration signals enables detect dim light, higher intensities intermittent exposure, whilst measures bright over extended periods time. Although photoreceptor similar, sensitivity thresholds differ markedly between mice humans. Mice entrain at approximately 1 lux few minutes, humans require high irradiance (>100's lux) long duration (>30 min). The basis this difference remains unclear. As our exposure is highly dynamic, because interactions complex difficult model, attempts develop evidence-based lighting enhance very challenging. A way forward will be define artificial natural "real world" where intensity, duration, spectral quality, time day, history age each assessed.

Язык: Английский

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The M5 Cell: A Color-Opponent Intrinsically Photosensitive Retinal Ganglion Cell

Neuron, Год журнала: 2017, Номер 97(1), С. 150 - 163.e4

Опубликована: Дек. 14, 2017

Язык: Английский

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Development, form, and function of the mouse visual thalamus

Journal of Neurophysiology, Год журнала: 2018, Номер 120(1), С. 211 - 225

Опубликована: Апрель 11, 2018

The dorsal lateral geniculate nucleus (dLGN) of the thalamus is exclusive relay retinal information en route to visual cortex. Although much our understanding about dLGN comes from studies done in higher mammals, such as cat and primate, mouse a model organism has moved forefront tractable experimental platform examine cell type-specific relations. This review highlights current knowledge development, structure, function dLGN.

Язык: Английский

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Axogenic mechanism enhances retinal ganglion cell excitability during early progression in glaucoma

Proceedings of the National Academy of Sciences, Год журнала: 2018, Номер 115(10)

Опубликована: Фев. 20, 2018

Diseases of the brain involve early axon dysfunction that often precedes outright degeneration. Pruning dendrites and their synapses represents a potential driver axonopathy by reducing activity. Optic nerve degeneration in glaucoma, world's leading cause irreversible blindness, involves stress to retinal ganglion cell (RGC) axons from sensitivity intraocular pressure (IOP). This also influences survival RGC excitatory retina. Here we tested individual RGCs identified type relationship between dendritic organization signaling light following modest, short-term elevations pressure. We found pruning occurred early, 2 wk elevation, independent whether responded onset (ON cells) or offset (OFF cells). was similarly ON OFF DBA/2J mouse, chronic glaucoma model. Paradoxically, all RGCs, even those with significant pruning, demonstrated transient increase firing response preferred stimulus on backdrop generally enhanced excitability. The increased not through conventional presynaptic signaling, but rather depended voltage-sensitive sodium channels transiently axon. Pruning, dysfunction, deficits visual acuity did progress 4 elevation. These results suggest neurodegeneration an axogenic counters IOP-related architecture slow progression maintain brain. Thus, exposure elevated IOP may precondition neural system further insult.

Язык: Английский

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A visual circuit uses complementary mechanisms to support transient and sustained pupil constriction

eLife, Год журнала: 2016, Номер 5

Опубликована: Сен. 26, 2016

Rapid and stable control of pupil size in response to light is critical for vision, but the neural coding mechanisms remain unclear. Here, we investigated basis by monitoring across time while manipulating each photoreceptor input or neurotransmitter output intrinsically photosensitive retinal ganglion cells (ipRGCs), a relay size. We show that transient sustained responses are mediated distinct photoreceptors neurotransmitters. Transient utilize from rod classical glutamate, adapt within minutes. In contrast, dominated non-conventional signaling mechanisms: melanopsin phototransduction ipRGCs neuropeptide PACAP, which provide maintenance day. These results highlight temporal switch circuit support proper behavioral dynamics.

Язык: Английский

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The injury resistant ability of melanopsin-expressing intrinsically photosensitive retinal ganglion cells

Neuroscience, Год журнала: 2014, Номер 284, С. 845 - 853

Опубликована: Ноя. 10, 2014

Neurons in the mammalian retina expressing photopigment melanopsin have been identified as a class of intrinsically photosensitive retinal ganglion cells (ipRGCs). This discovery more than decade ago has opened up an exciting new field research, and following initial identification cells, several subtypes described. A number studies shown that ipRGCs subserve photoentrainment circadian rhythms. They also influence other non-image forming functions visual system, such pupillary light reflex, sleep, cognition, mood, aversion development retina. These novel neurons form vision by contributing to contrast detection. Furthermore, are injury-resistant optic nerve injury, animal models glaucoma, patients with mitochondrial neuropathies, i.e., Leber's hereditary neuropathy dominant atrophy. There is indication these may be resistant glutamate-induced excitotoxicity. Herein we provide overview discuss character under certain pathological experimental conditions.

Язык: Английский

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Melanopsin Contributions to the Representation of Images in the Early Visual System

Current Biology, Год журнала: 2017, Номер 27(11), С. 1623 - 1632.e4

Опубликована: Май 18, 2017

Melanopsin photoreception enhances retinal responses to variations in ambient light (irradiance) and drives non-image-forming visual reflexes such as circadian entrainment [1Schmidt T.M. Chen S.K. Hattar S. Intrinsically photosensitive ganglion cells: many subtypes, diverse functions.Trends Neurosci. 2011; 34: 572-580Abstract Full Text PDF PubMed Scopus (378) Google Scholar, 2Schmidt Do M.T. Dacey D. Lucas R. Matynia A. Melanopsin-positive intrinsically from form function.J. 31: 16094-16101Crossref (170) 3Do Yau K.W. cells.Physiol. Rev. 2010; 90: 1547-1581Crossref (280) 4Sexton T. Buhr E. Van Gelder R.N. mechanisms of non-visual ocular photoreception.J. Biol. Chem. 2012; 287: 1649-1656Crossref (58) 5Rollag M.D. Berson D.M. Provencio I. Melanopsin, ganglion-cell photoreceptors, mammalian photoentrainment.J. Rhythms. 2003; 18: 227-234Crossref (111) 6Bailes H.J. R.J. inner photoreception.Cell. Mol. Life Sci. 67: 99-111Crossref (87) Scholar]. signals also reach brain regions responsible for vision [7Brown Gias C. Hatori M. Keding S.R. Semo Coffey P.J. Gigg J. Piggins H.D. Panda contributions irradiance coding the thalamo-cortical system.PLoS 8: e1000558Crossref (188) 8Dacey Liao H.W. Peterson B.B. Robinson F.R. Smith V.C. Pokorny Gamlin P.D. Melanopsin-expressing cells primate retina signal colour project LGN.Nature. 2005; 433: 749-754Crossref (993) 9Ecker J.L. Dumitrescu O.N. Wong K.Y. Alam N.M. LeGates Renna J.M. Prusky G.T. photoreceptors: cellular diversity role pattern vision.Neuron. 49-60Abstract (469) Scholar], but melanopsin's contribution, if any, encoding images remains unclear. We addressed this deficit using principles receptor silent substitution present which visibility melanopsin versus rods+cones was independently modulated, we recorded evoked mouse dorsal lateral geniculate nucleus (dLGN; thalamic relay cortical vision). Approximately 20% dLGN units responded patterns visible only melanopsin, revealing that alone can convey spatial information. Spatial receptive fields (RFs) mapped melanopsin-isolating stimuli had ON centers with diameters ∼13°. rod+cone differed temporal domain, slow changes radiance (<0.9 Hz) stationary were deficient when rendered invisible melanopsin. employed these data devise test a mathematical model involvement applied it, along further experimental recordings, explore under simulated active view natural scenes. Our findings reveal representation scenes containing local correlations radiance, compensating high frequency bias cone negative correlation between magnitude direction view. Together, distinct contribution images, predicting that, view, augments early system's ability encode over moderate scales.

Язык: Английский

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Organization of the dorsal lateral geniculate nucleus in the mouse

Visual Neuroscience, Год журнала: 2017, Номер 34

Опубликована: Янв. 1, 2017

Abstract The dorsal lateral geniculate nucleus (dLGN) of the thalamus is principal conduit for visual information from retina to cortex. Viewed initially as a simple relay, recent studies in mouse reveal far greater complexity way input combined, transmitted, and processed dLGN. Here we consider structural functional organization retinogeniculate pathway by examining patterns retinal projections dLGN how they converge onto thalamocortical neurons shape flow

Язык: Английский

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Distinct ipRGC subpopulations mediate light’s acute and circadian effects on body temperature and sleep

eLife, Год журнала: 2019, Номер 8

Опубликована: Июль 23, 2019

The light environment greatly impacts human alertness, mood, and cognition by both acute regulation of physiology indirect alignment circadian rhythms. These processes require the melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs), but relevant downstream brain areas involved remain elusive. ipRGCs project widely in brain, including to central pacemaker, suprachiasmatic nucleus (SCN). Here we show that body temperature sleep responses exposure are absent after genetic ablation all except a subpopulation projects SCN. Furthermore, chemogenetic activation avoid SCN, these sufficient for changes temperature. Our results challenge idea SCN is major relay effects on non-image forming behaviors identify sensory initiate light's profound sleep.

Язык: Английский

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