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The Journal of Comparative Neurology Oct 2009Horizontal cells (HCs) are involved in establishing the center-surround receptive field organization of photoreceptor and bipolar cells. In many species, HCs respond...
Horizontal cells (HCs) are involved in establishing the center-surround receptive field organization of photoreceptor and bipolar cells. In many species, HCs respond differentially to colors and may play a role in color vision. An earlier study from our laboratory suggested that four types of HCs exist in the zebrafish retina: three cone HCs (H1, H2 and H3) and one rod HC. In this study, we describe their photoreceptor connections. Cones are arranged in a mosaic in which rows of alternating blue (B)- and ultraviolet (UV)-sensitive single cones alternate with rows of red (R)- and green (G)-sensitive double cones; the G cones are adjacent to UV cones and B cones adjacent to R cones. Two small-field (H1 and H2) and two large-field (H3 and rod HC) cells were observed. The cone HC dendritic terminals connected to cones with single boutons, doublets, or rosettes, whereas the rod HCs connected to rods with single boutons. The single boutons/doublets/rosettes of cone HCs were arranged in double rows separated by single rows for H1 cells, in pairs and singles for H2 cells, and in a rectilinear pattern for H3 cells. These connectivity patterns suggest that H1 cells contact R, G, and B cones, H2 cells G, B, and UV cones, and H3 cells B and UV cones. These predictions were confirmed by applying the DiI method to SWS1-GFP retinas whose UV cones express green fluorescent protein. Each rod HC was adjacent to the soma or axon of a DiI-labeled cone HC and connected to 50-200 rods.
Topics: Animals; Dendrites; Microscopy, Confocal; Neural Pathways; Photoreceptor Cells, Vertebrate; Retinal Cone Photoreceptor Cells; Retinal Horizontal Cells; Retinal Rod Photoreceptor Cells; Ultraviolet Rays; Zebrafish
PubMed: 19655401
DOI: 10.1002/cne.22135 -
Stem Cell Reports Aug 2022Regenerative therapies aimed at replacing photoreceptors are a promising approach for the treatment of otherwise incurable causes of blindness. However, such therapies...
Regenerative therapies aimed at replacing photoreceptors are a promising approach for the treatment of otherwise incurable causes of blindness. However, such therapies still face significant hurdles, including the need to improve subretinal delivery and long-term survival rate of transplanted cells, and promote sufficient integration into the host retina. Here, we successfully delivered in vitro-derived human photoreceptor precursor cells (PRPCs; also known as immature photoreceptors) to the subretinal space of seven normal and three rcd1/PDE6B mutant dogs with advanced inherited retinal degeneration. Notably, while these xenografts were rejected in dogs that were not immunosuppressed, transplants in most dogs receiving systemic immunosuppression survived up to 3-5 months postinjection. Moreover, differentiation of donor PRPCs into photoreceptors with synaptic pedicle-like structures that established contact with second-order neurons was enhanced in rcd1/PDE6B mutant dogs. Together, our findings set the stage for evaluating functional vision restoration following photoreceptor replacement in canine models of inherited retinal degeneration.
Topics: Animals; Cell Differentiation; Dogs; Humans; Immunosuppression Therapy; Photoreceptor Cells; Photoreceptor Cells, Vertebrate; Retina; Retinal Degeneration
PubMed: 35905738
DOI: 10.1016/j.stemcr.2022.06.009 -
Neuron Jun 2019Light drives vision by directly activating opsin-based visual pigments in rod and cone photoreceptors. In this issue of Neuron, Morshedian et al. (2019) show that light...
Light drives vision by directly activating opsin-based visual pigments in rod and cone photoreceptors. In this issue of Neuron, Morshedian et al. (2019) show that light also drives regeneration of the cone visual pigments via an elegant biochemical mechanism in Müller glial cells of the neural retina that can contribute to sustained cone function under daytime conditions.
Topics: Opsins; Regeneration; Retina; Retinal Cone Photoreceptor Cells; Retinal Pigments; Retinal Rod Photoreceptor Cells; Rod Opsins
PubMed: 31220441
DOI: 10.1016/j.neuron.2019.05.051 -
Vision Research Jan 2009In the tiger salamander retina, visual signals are transmitted to the inner retina via six morphologically distinct types of photoreceptors: large/small rods,...
In the tiger salamander retina, visual signals are transmitted to the inner retina via six morphologically distinct types of photoreceptors: large/small rods, large/small single cones, and double cones composed of principal and accessory members. The objective of this study was to determine the morphology of these photoreceptors and their synaptic interconnection with bipolar cells and horizontal cells in the outer plexiform layer (OPL). Here we showed that glutamate antibodies labeled all photoreceptors and recovering antibodies strongly labeled all cones and weakly labeled all rods. Antibodies against calbindin selectively stained accessory members of double cones. Antibodies against S-cone opsin stained small rods, a subpopulation of small single cones, and the outer segments of accessory double cones and a subtype of unidentified single cones. On average, large rods and small S-cone opsin positive rods accounted for 98.6% and 1.4% of all rods, respectively. Large/small cones, principle/accessory double cones, S-cone opsin positive small single cones, and S-cone opsin positive unidentified single cones accounted for about 66.9%, 23%, 4.5%, and 5.6% of the total cones, respectively. Moreover, the differential connection between rods/cones and bipolar/horizontal cells and the wide distribution of AMPA receptor subunits GluR2/3 and GluR4 at the rod/cone synapses were observed. These results provide anatomical evidence for the physiological findings that bipolar/horizontal cells in the salamander retina are driven by rod/cone inputs of different weights, and that AMPA receptors play an important role in glutamatergic neurotransmission at the first visual synapses. The different photoreceptors selectively contacting bipolar and horizontal cells support the idea that visual signals may be conveyed to the inner retina by different functional pathways in the outer retina.
Topics: Ambystoma; Animals; Glutamic Acid; Immunohistochemistry; Larva; Microscopy, Confocal; Neural Pathways; Opsins; Photoreceptor Cells; Receptors, AMPA; Retinal Bipolar Cells; Retinal Cone Photoreceptor Cells; Retinal Horizontal Cells; Retinal Rod Photoreceptor Cells; Synapses; Visual Pathways
PubMed: 18977238
DOI: 10.1016/j.visres.2008.09.031 -
Human Molecular Genetics Oct 2016Ciliary defects can result in severe disorders called ciliopathies. Mutations in NPHP5 cause a ciliopathy characterized by severe childhood onset retinal blindness,...
Ciliary defects can result in severe disorders called ciliopathies. Mutations in NPHP5 cause a ciliopathy characterized by severe childhood onset retinal blindness, Leber congenital amaurosis (LCA), and renal disease. Using the canine NPHP5-LCA model we compared human and canine retinal phenotypes, and examined the early stages of photoreceptor development and degeneration, the kinetics of photoreceptor loss, the progression of degeneration and the expression profiles of selected genes. NPHP5-mutant dogs recapitulate the human phenotype of very early loss of rods, and relative retention of the central retinal cone photoreceptors that lack function. In mutant dogs, rod and cone photoreceptors have a sensory cilium, but develop and function abnormally and then rapidly degenerate; L/M cones are more severely affected than S-cones. The lack of outer segments in mutant cones indicates a ciliary dysfunction. Genes expressed in mutant rod or both rod and cone photoreceptors show significant downregulation, while those expressed only in cones are unchanged. Many genes in cell-death and -survival pathways also are downregulated. The canine disease is a non-syndromic LCA-ciliopathy, with normal renal structures and no CNS abnormalities. Our results identify the critical time points in the pathogenesis of the photoreceptor disease, and bring us closer to defining a potential time window for testing novel therapies for translation to patients.
Topics: Animals; Calmodulin-Binding Proteins; Cilia; Disease Models, Animal; Dogs; Humans; Leber Congenital Amaurosis; Mutation; Photoreceptor Cells; Retina; Retinal Cone Photoreceptor Cells; Retinal Rod Photoreceptor Cells
PubMed: 27506978
DOI: 10.1093/hmg/ddw254 -
Scientific Reports Jul 2016Retinal bipolar cells (BCs) divide photoreceptor output into different channels for the parallel extraction of temporal and chromatic stimulus properties. In rodents,...
Retinal bipolar cells (BCs) divide photoreceptor output into different channels for the parallel extraction of temporal and chromatic stimulus properties. In rodents, five types of OFF BCs have been differentiated, based on morphological and functional criteria, but their electrophysiological characterization remains incomplete. This study analyzed OFF BCs with the patch clamp technique in acute slices of rat retina. Their specific voltage-dependent currents and glutamate responses are shown to represent individual fingerprints which define the signal processing and filtering properties of each cell type and allow their unequivocal identification. Two additions to the rat BC repertoire are presented: OFF BC-2', a variation of BC-2 with wider axonal arbours and prominent Na(+) currents, is described for the first time in rodents, and OFF BC-3b, previously identified in mouse, is electrophysiologically characterized in rat. Moreover, the glutamate responses of rat OFF BCs are shown to be differentially sensitive to AMPA- and kainate-receptor blockers and to modulation by nitric oxide (NO) through a cGMP-dependent mechanism. These results contribute to our understanding of the diversity and function of bipolar cells in mammals.
Topics: Animals; Axons; Electrophysiological Phenomena; Patch-Clamp Techniques; Photic Stimulation; Photoreceptor Cells; Rats; Receptors, Kainic Acid; Retina; Retinal Bipolar Cells; Retinal Cone Photoreceptor Cells
PubMed: 27457753
DOI: 10.1038/srep30259 -
The Journal of Veterinary Medical... Mar 2018Owl monkeys are the only one species possessing the nocturnal lifestyles among the simian monkeys. Their eyes and retinas have been interested associating with the...
Owl monkeys are the only one species possessing the nocturnal lifestyles among the simian monkeys. Their eyes and retinas have been interested associating with the nocturnal adaptation. We examined the cellular specificity and electroretinogram (ERG) reactivity in the retina of the owl monkeys by comparison with the squirrel monkeys, taxonomically close-species and expressing diurnal behavior. Owl monkeys did not have clear structure of the foveal pit by the funduscope, whereas the retinal wholemount specimens indicated a small-condensed spot of the ganglion cells. There were abundant numbers of the rod photoreceptor cells in owl monkeys than those of the squirrel monkeys. However, the owl monkeys' retina did not possess superiority for rod cell-reactivity in the scotopic ERG responses. Scanning electron microscopic observation revealed that the rod cells in owl monkeys' retina had very small-sized inner and outer segments as compared with squirrel monkeys. Owl monkeys showed typical nocturnal traits such as rod-cell dominance. However, the individual photoreceptor cells seemed to be functionally weak for visual capacity, caused from the morphological immaturity at the inner and outer segments.
Topics: Animals; Aotidae; Electroretinography; Female; Male; Microscopy, Electron, Scanning; Night Vision; Ophthalmoscopes; Photoreceptor Cells, Vertebrate; Retina; Retinal Rod Photoreceptor Cells; Saimiri
PubMed: 29375079
DOI: 10.1292/jvms.17-0418 -
Developmental Cell Feb 2009In the developing retina the nuclear hormone receptor Nr2e3 has dual roles, promoting expression of rod-specific genes and repressing expression of cone specific genes.... (Review)
Review
In the developing retina the nuclear hormone receptor Nr2e3 has dual roles, promoting expression of rod-specific genes and repressing expression of cone specific genes. In a recent issue of Neuron, Onishi et al. show that PIAS3-mediated SUMOylation of Nr2e3 plays an essential role in the specification of rod photoreceptors by converting Nr2e3 to a potent repressor of cone gene expression.
Topics: Animals; Developmental Biology; Gene Expression Regulation, Developmental; Mice; Models, Biological; Molecular Chaperones; Orphan Nuclear Receptors; Photoreceptor Cells; Protein Inhibitors of Activated STAT; Receptors, Cytoplasmic and Nuclear; Retina; Retinal Cone Photoreceptor Cells; Retinal Rod Photoreceptor Cells; Signal Transduction; Small Ubiquitin-Related Modifier Proteins
PubMed: 19217419
DOI: 10.1016/j.devcel.2009.01.017 -
Neuron May 1998
Review
Topics: Animals; Biological Clocks; Humans; Photoreceptor Cells; Retinal Pigments; Sunlight
PubMed: 9620688
DOI: 10.1016/s0896-6273(00)80464-x -
The Journal of Physiology Jun 2017
Topics: Adaptation, Physiological; Photoreceptor Cells; Retinal Rod Photoreceptor Cells
PubMed: 28261801
DOI: 10.1113/JP274146