Dopamine regulates melanopsin mRNA expression in intrinsically photosensitive retinal ganglion cells

  title={Dopamine regulates melanopsin mRNA expression in intrinsically photosensitive retinal ganglion cells},
  author={Katsuhiko Sakamoto and Cuimei Liu and Manami Kasamatsu and Nikita V Pozdeyev and P. Michael Iuvone and Gianluca Tosini},
  journal={European Journal of Neuroscience},
In mammals a subpopulation of retinal ganglion cells are intrinsically photosensitive (ipRGCs), express the photopigment melanopsin, and play an important role in the regulation of the nonimage‐forming visual system. We have recently reported that melanopsin mRNA and protein levels in the rat retina are under photic and circadian control. The aim of the present work was to investigate the mechanisms that control melanopsin expression in the rat retina. We discovered that dopamine (DA) is… 

Phosphorylation of Mouse Melanopsin by Protein Kinase A

A heterologous expression system is used to demonstrate that mouse melanopsin can be phosphorylated by protein kinase A, and that phosphorylation can inhibit melanopsIn signaling in HEK cells, and it is suggested that the attenuation of the melanopsins-based light response by dopamine is mediated by direct PKA phosphorylations of melanopin, rather than phosphorylate of a downstream component of the signaling cascade.

Acute photoreceptor degeneration down-regulates melanopsin expression in adult rat retina

Dopaminergic modulation of ganglion‐cell photoreceptors in rat

It is suggested that dopamine, acting via D1‐family receptors, alters the responses of ipRGCs and thus of non‐image‐forming vision.

Genetic Advances in Ophthalmology: The Role of Melanopsin-Expressing, Intrinsically Photosensitive Retinal Ganglion Cells in the Circadian Organization of the Visual System

This review will cover the role that melanopsin and ipRGCs play in the circadian organization of the visual system and note that both central and peripheral oscillators share an endogenous, circadian-driven, transcription–translation feedback loop that cycles with a periodicity of approximately 24 hours.

Synaptic contact between melanopsin-containing retinal ganglion cells and rod bipolar cells.

It is demonstrated that melanopsin-containing RGCs have synaptic contact with PKC/CtBP2-containing rod bipolar cells and TH/VMAT2-immunoreactive amacrine cells through axodendritic and axosomatic contact, supporting electrophysiological observations that rods and cones signal to the melanopsIn-containing intrinsically photosensitive R GCs.

Co-Expression of Two Subtypes of Melatonin Receptor on Rat M1-Type Intrinsically Photosensitive Retinal Ganglion Cells

It is highly plausible that retinal melatonin may directly modulate the activity of ipRGCs, thus regulating non-image forming visual functions, and is studied by double-staining immunohistochemical technique.

Intraretinal signaling by ganglion cell photoreceptors to dopaminergic amacrine neurons

Ganglion-cell photoreceptors provide excitatory drive to DA neurons, most likely by way of the coramification of their dendrites and the processes of DA neurons in the inner plexiform layer, which provides a novel basis for the restructuring of retinal circuits by light.

Melatonin modulates M4-type ganglion-cell photoreceptors




Classical Photoreceptors Regulate Melanopsin mRNA Levels in the Rat Retina

The results suggest that classical photoreceptors (rods and cones) regulate the expression of melanopsin mRNA in the rat, and may provide an important insight on melanopigment function in patients affected by retinitis pigmentosa.

Melanopsin-Containing Retinal Ganglion Cells: Architecture, Projections, and Intrinsic Photosensitivity

It is shown that melanopsin is present in cell bodies, dendrites, and proximal axonal segments of a subset of rat RGCs, most likely the visual pigment of phototransducing R GCs that set the circadian clock and initiate other non–image-forming visual functions.

Illumination of the Melanopsin Signaling Pathway

It is found that expression of melanopsin in Xenopus oocytes results in light-dependent activation of membrane currents through the Gαq/Gα11 G protein pathway, with an action spectrum closely matching that of melanpsin-expressing ipRGCs and of behavioral responses to light in mice lacking rods and cones.

Induction of photosensitivity by heterologous expression of melanopsin

It is concluded that mammalian melanopsin is a functional sensory photopigment, that it is the photopigsment of ganglion-cell photoreceptors, and that these photoreCEPTors may use an invertebrate-like phototransduction cascade.

The Photopigment Melanopsin Is Exclusively Present in Pituitary Adenylate Cyclase-Activating Polypeptide-Containing Retinal Ganglion Cells of the Retinohypothalamic Tract

Cloned rat melanopsin photopigment cDNA is cloned and in situ hybridization histochemistry combined with immunohistochemistry and colocalization studies reveal that melanops in was found exclusively in the PACAP-containing retinal ganglion cells located at the surface of somata and dendrites.

Intrinsically photosensitive retinal ganglion cells detect light with a vitamin A-based photopigment, melanopsin.

  • Yingbin FuH. Zhong K. Yau
  • Biology
    Proceedings of the National Academy of Sciences of the United States of America
  • 2005
Study of mice lacking RPE65, a protein essential for the regeneration of rod and cone pigments, and exogenous all-trans-retinal was also able to rescue the low sensitivity of rpe65-/- ipRGCs suggest melanopsin could be a bistable pigment.

Melanopsin is expressed in PACAP-containing retinal ganglion cells of the human retinohypothalamic tract.

Given the expression of melanopsin in PACAP-containing RGCs of the human RHT, this photoreceptor is a likely first base in the chain of events leading to photoentrainment of both normal and blind people.

A Broad Role for Melanopsin in Nonvisual Photoreception

The results suggest that melanopsin expression defines a subset of RGCs that play a broad role in theregulation of nonvisual photoreception, providing collateralized projections that contribute to circadian entrainment, negative masking, the regulation of sleep-wake states, and the pupillary light reflex.

Addition of human melanopsin renders mammalian cells photoresponsive

It is shown that heterologous expression of human melanopsin in a mouse paraneuronal cell line (Neuro-2a) is sufficient to render these cells photoreceptive and that melanopigment functions as a bistable pigment in this system, having an intrinsic photoisomerase regeneration function that is chromatically shifted to longer wavelengths.