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Physiological Reviews Oct 2010Life on earth is subject to alternating cycles of day and night imposed by the rotation of the earth. Consequently, living things have evolved photodetective systems to... (Review)
Review
Life on earth is subject to alternating cycles of day and night imposed by the rotation of the earth. Consequently, living things have evolved photodetective systems to synchronize their physiology and behavior with the external light-dark cycle. This form of photodetection is unlike the familiar "image vision," in that the basic information is light or darkness over time, independent of spatial patterns. "Nonimage" vision is probably far more ancient than image vision and is widespread in living species. For mammals, it has long been assumed that the photoreceptors for nonimage vision are also the textbook rods and cones. However, recent years have witnessed the discovery of a small population of retinal ganglion cells in the mammalian eye that express a unique visual pigment called melanopsin. These ganglion cells are intrinsically photosensitive and drive a variety of nonimage visual functions. In addition to being photoreceptors themselves, they also constitute the major conduit for rod and cone signals to the brain for nonimage visual functions such as circadian photoentrainment and the pupillary light reflex. Here we review what is known about these novel mammalian photoreceptors.
Topics: Animals; Brain; Humans; Retinal Cone Photoreceptor Cells; Retinal Ganglion Cells; Retinal Rod Photoreceptor Cells; Sleep
PubMed: 20959623
DOI: 10.1152/physrev.00013.2010 -
Cell and Tissue Research Aug 2013Imaging has gained a key role in modern glaucoma management. Traditionally, interest was directed toward the appearance of the optic nerve head and the retinal nerve... (Review)
Review
Imaging has gained a key role in modern glaucoma management. Traditionally, interest was directed toward the appearance of the optic nerve head and the retinal nerve fiber layer. With the improvement of the resolution of optical coherence tomography, the ganglion cell complex has also become routinely accessible in the clinic. Further advances have been made in understanding the structure-function relationship in glaucoma. Nevertheless, direct imaging of the retinal ganglion cells in glaucoma would be advantageous. With the currently used techniques, this goal cannot be achieved, because the transversal resolution is limited by aberrations of the eye. The use of adaptive optics has significantly improved transversal resolution, and the imaging of several cell types including cones and astrocytes has become possible. Imaging of retinal ganglion cells, however, still remains a problem, because of the transparency of these cells. However, the visualization of retinal ganglion cells and their dendrites has been achieved in animal models. Furthermore, attempts have been made to visualize the apoptosis of retinal ganglion cells in vivo. Implementation of these techniques in clinical practice will probably improve glaucoma care and facilitate the development of neuroprotective strategies.
Topics: Animals; Diagnostic Imaging; Glaucoma; Humans; Retinal Ganglion Cells; Tomography, Optical Coherence
PubMed: 23512142
DOI: 10.1007/s00441-013-1600-3 -
Gene Expression Patterns : GEP Dec 2018The acetylation state of histones has been used as an indicator of the developmental state of progenitor and differentiating cells. The goal of this study was to...
BACKGROUND
The acetylation state of histones has been used as an indicator of the developmental state of progenitor and differentiating cells. The goal of this study was to determine the nuclear localization patterns of Class I histone deacetylases (HDACs) in retinal progenitor cells (RPCs) and retinal ganglion cells (RGCs), as the first step in understanding their potential importance in cell fate determination within the murine retina.
RESULTS
The only HDAC to label RPC nuclei at E16 and P5 was HDAC1. In contrast, there was generally increased nuclear localization of all Class I HDACs in differentiating RGCs. Between P5 and P30, SOX2 expression becomes restricted to Müller glial, cholinergic amacrine cells, and retinal astrocytes. Cholinergic amacrine showed a combination of changes in nuclear localization of Class I HDACs. Strikingly, although Müller glia and retinal astrocytes express many of the same genes, P30 Müller glial cells showed nuclear localization only of HDAC1, while retinal astrocytes were positive for HDACs 1, 2, and 3.
CONCLUSION
These results indicate there may be a role for one or more of the Class I HDACs in retinal cell type-specific differentiation.
Topics: Acetylation; Animals; Cell Differentiation; Cells, Cultured; Embryo, Mammalian; Gene Expression Regulation, Developmental; Gene Expression Regulation, Enzymologic; Histone Deacetylases; Mice; Mice, Inbred C57BL; Retinal Ganglion Cells; Stem Cells
PubMed: 30179675
DOI: 10.1016/j.gep.2018.08.007 -
The Journal of Comparative Neurology Apr 2020Multiple retinal ganglion cell (RGC) types in the mouse retina mediate pattern vision by responding to specific features of the visual scene. The M4 and M5...
Multiple retinal ganglion cell (RGC) types in the mouse retina mediate pattern vision by responding to specific features of the visual scene. The M4 and M5 melanopsin-expressing, intrinsically photosensitive retinal ganglion cell (ipRGC) subtypes are two RGC types that are thought to play major roles in pattern vision. The M4 ipRGCs overlap in population with ON-alpha RGCs, while M5 ipRGCs were recently reported to exhibit opponent responses to different wavelengths of light (color opponency). Despite their seemingly distinct roles in visual processing, previous reports have suggested that these two populations may exhibit overlap in their morphological and functional properties, which calls into question whether these are in fact distinct RGC types. Here, we show that M4 and M5 ipRGCs are distinct morphological classes of ipRGCs, but they cannot be exclusively differentiated based on color opponency and dendritic morphology as previously reported. Instead, we find that M4 and M5 ipRGCs can only be distinguished based on soma size and the number of dendritic branch points in combination with SMI-32 immunoreactivity. These results have important implications for clearly defining RGC types and their roles in visual behavior.
Topics: Animals; Female; Male; Mice; Retinal Ganglion Cells
PubMed: 31691279
DOI: 10.1002/cne.24806 -
PloS One 2021The retinal output is the sole source of visual information for the brain. Studies in non-primate mammals estimate that this information is carried by several dozens of...
The retinal output is the sole source of visual information for the brain. Studies in non-primate mammals estimate that this information is carried by several dozens of retinal ganglion cell types, each informing the brain about different aspects of a visual scene. Even though morphological studies of primate retina suggest a similar diversity of ganglion cell types, research has focused on the function of only a few cell types. In human retina, recordings from individual cells are anecdotal or focus on a small subset of identified types. Here, we present the first systematic ex-vivo recording of light responses from 342 ganglion cells in human retinas obtained from donors. We find a great variety in the human retinal output in terms of preferences for positive or negative contrast, spatio-temporal frequency encoding, contrast sensitivity, and speed tuning. Some human ganglion cells showed similar response behavior as known cell types in other primate retinas, while we also recorded light responses that have not been described previously. This first extensive description of the human retinal output should facilitate interpretation of primate data and comparison to other mammalian species, and it lays the basis for the use of ex-vivo human retina for in-vitro analysis of novel treatment approaches.
Topics: Animals; Contrast Sensitivity; Humans; Light; Photic Stimulation; Retinal Ganglion Cells
PubMed: 33592045
DOI: 10.1371/journal.pone.0246952 -
Methods in Molecular Biology (Clifton,... 2018Labeling of cellular structures is of fundamental importance in the investigation of diseases of the central nervous system. Biolistic labeling of retinal ganglion cells...
Labeling of cellular structures is of fundamental importance in the investigation of diseases of the central nervous system. Biolistic labeling of retinal ganglion cells (RGCs) allows visualization of dendritic and synaptic structures of RGCs in retinal explants from animal models of experimental glaucoma. This technique sparsely labels RGCs, and, due to the stochastic nature of the particle delivery, all RGC types can be potentially observed in the labeled tissue. Quantification of dendritic and synaptic properties permits examination of the specific alterations to RGC morphology at different stages of degeneration, such as dendritic shrinkage and excitatory synapse loss.
Topics: Animals; Biolistics; Dendrites; Disease Models, Animal; Glaucoma; Mice; Retinal Ganglion Cells; Synapses
PubMed: 29190026
DOI: 10.1007/978-1-4939-7407-8_14 -
Investigative Ophthalmology & Visual... Dec 2013
Topics: Animals; Cell Line, Transformed; Retinal Ganglion Cells
PubMed: 24302631
DOI: 10.1167/iovs.13-13292 -
Proceedings of the National Academy of... Jan 1996Retinal ganglion cells are the output neurons that encode and transmit information from the eye to the brain. Their diverse physiologic and anatomic properties have been... (Review)
Review
Retinal ganglion cells are the output neurons that encode and transmit information from the eye to the brain. Their diverse physiologic and anatomic properties have been intensively studied and appear to account well for a number of psychophysical phenomena such as lateral inhibition and chromatic opponency. In this paper, we summarize our current view of retinal ganglion cell properties and pose a number of questions regarding underlying molecular mechanisms. As an example of one approach to understanding molecular mechanisms, we describe recent work on several POU domain transcription factors that are expressed in subsets of retinal ganglion cells and that appear to be involved in ganglion cell development.
Topics: Animals; Color Perception; Light; Retina; Retinal Ganglion Cells; Space Perception; Synaptic Transmission; Transcription Factors
PubMed: 8570601
DOI: 10.1073/pnas.93.2.596 -
The European Journal of Neuroscience Apr 2019The retinogeniculate synapse transmits information from retinal ganglion cells (RGC) in the eye to thalamocortical relay neurons in the visual thalamus, the dorsal...
The retinogeniculate synapse transmits information from retinal ganglion cells (RGC) in the eye to thalamocortical relay neurons in the visual thalamus, the dorsal lateral geniculate nucleus (dLGN). Studies in mice have identified genetic markers for distinct classes of RGCs encoding different features of the visual space, facilitating the dissection of RGC subtype-specific physiology and anatomy. In this study, we examine the morphological properties of axon arbors of the BD-RGC class of ON-OFF direction selective cells that, by definition, exhibit a stereotypic dendritic arbor and termination pattern in the retina. We find that axon arbors from the same class of RGCs exhibit variations in their structure based on their target region of the dLGN. Our findings suggest that target regions may influence the morphologic and synaptic properties of their afferent inputs.
Topics: Animals; Axons; Geniculate Bodies; Mice; Neuronal Plasticity; Retinal Ganglion Cells
PubMed: 29883007
DOI: 10.1111/ejn.13986 -
Medical Science Monitor : International... Jan 2020Nuclear factor erythroid 2-related factor 2 (Nrf2) acts as a regulator of many biological processes and plays an essential role in preventing oxidation, inflammation,... (Review)
Review
Nuclear factor erythroid 2-related factor 2 (Nrf2) acts as a regulator of many biological processes and plays an essential role in preventing oxidation, inflammation, and fibrosis. In the past 20 years, there has been increasing research on the role of Nrf2 and oxidative stress in human glaucoma, including the roles of inflammation, trabecular meshwork cells, retinal ganglion cells, Tenon's capsule, antioxidants, fibrosis, and noncoding RNAs. Studies have shown that the upregulation of Nrf2 can reduce damage from oxidative stress in the trabecular meshwork cells and the retinal ganglion cells, reduce fibrosis in Tenon's capsule fibroblasts, which may reduce the progression of fibrosis after surgery for glaucoma. The regulatory roles of Nrf2, microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and exogenous compounds on trabecular meshwork cells (TMCs) and retinal ganglion cells have also been studied. The use of Nrf2 agonists, including noncoding RNAs, control the expression of Nrf2 through signaling pathways that continue to be investigated to identify effective treatments to improve clinical outcome following surgery for glaucoma. This review of publications between 1999 and 2019 aims to focus on the potential mechanisms of Nrf2 in the occurrence and development of glaucoma and the prognosis following surgical treatment. Also, several factors that induce the expression of Nrf2 in trabecular meshwork cells, retinal ganglion cells, and human Tenon's capsule fibroblasts are discussed.
Topics: Animals; Glaucoma; Humans; NF-E2-Related Factor 2; Oxidative Stress; RNA, Long Noncoding; Retinal Ganglion Cells; Trabecular Meshwork
PubMed: 31949124
DOI: 10.12659/MSM.921514