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Mattern KMJ, Blancas-Velázquez AS, Ngo MT, Bille S, Hertz H, Bering T, Rath MF. The ISL LIM-homeobox 2 transcription factor is negatively regulated by circadian adrenergic signaling to repress the expression of Aanat in pinealocytes of the rat pineal gland. J Pineal Res 2023; 75:e12905. [PMID: 37649242 DOI: 10.1111/jpi.12905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 07/19/2023] [Accepted: 08/07/2023] [Indexed: 09/01/2023]
Abstract
Melatonin is synthesized in the pineal gland during nighttime in response to nocturnal increase in the activity of the enzyme aralkylamine N-acetyltransferase (AANAT), the transcription of which is modulated by several homeodomain transcription factors. Recent work suggests that the homeodomain transcription factor ISL LIM homeobox 2 (ISL2) is expressed in the pineal gland, but its role is currently unknown. With the purpose of identifying the mechanisms that control pineal expression of Isl2 and the possible function of Isl2 in circadian pineal biology, we report that Isl2 is specifically expressed in the pinealocytes of the rat pineal gland. Its expression exhibits a 24 h rhythm with high transcript and protein levels during the day and a trough in the second half of the night. This rhythm persists in darkness, and lesion studies reveal that it requires intact function of the suprachiasmatic nuclei, suggesting intrinsic circadian regulation. In vivo and in vitro experiments show that pineal Isl2 expression is repressed by adrenergic signaling acting via cyclic AMP; further, Isl2 is negatively regulated by the nocturnal transcription factor cone-rod homeobox. During development, pineal Isl2 expression is detectable from embryonic day 19, preceding Aanat by several days. In vitro knockdown of Isl2 is accompanied by an increase in Aanat transcript levels suggesting that ISL2 represses its daytime expression. Thus, rhythmic expression of ISL2 in pinealocytes is under the control of the suprachiasmatic nucleus acting via adrenergic signaling in the gland to repress nocturnal expression, while ISL2 itself negatively regulates daytime pineal expression of Aanat and thereby suggestively enhances the circadian rhythm in melatonin synthesis.
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Affiliation(s)
- Kuno M-J Mattern
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Aurea S Blancas-Velázquez
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Mikaella T Ngo
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Signe Bille
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Henrik Hertz
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tenna Bering
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Martin F Rath
- Department of Neuroscience, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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2
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Zhang P, Vafaeva O, Dolf C, Ma Y, Wang G, Cho J, Chan HHL, Marsh-Armstrong N, Zawadzki RJ. Evaluating the performance of OCT in assessing static and potential dynamic properties of the retinal ganglion cells and nerve fiber bundles in the living mouse eye. BIOMEDICAL OPTICS EXPRESS 2023; 14:6422-6441. [PMID: 38420317 PMCID: PMC10898556 DOI: 10.1364/boe.504637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/08/2023] [Accepted: 11/11/2023] [Indexed: 03/02/2024]
Abstract
Glaucoma is a group of eye diseases characterized by the thinning of the retinal nerve fiber layer (RNFL), which is primarily caused by the progressive death of retinal ganglion cells (RGCs). Precise monitoring of these changes at a cellular resolution in living eyes is significant for glaucoma research. In this study, we aimed to assess the effectiveness of temporal speckle averaging optical coherence tomography (TSA-OCT) and dynamic OCT (dOCT) in examining the static and potential dynamic properties of RGCs and RNFL in living mouse eyes. We evaluated parameters such as RNFL thickness and possible dynamics, as well as compared the ganglion cell layer (GCL) soma density obtained from in vivo OCT, fluorescence scanning laser ophthalmoscopy (SLO), and ex vivo histology.
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Affiliation(s)
- Pengfei Zhang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, 116024, China
- UC Davis EyePod Small Animals Ocular Imaging Laboratory, University of California Davis, Davis, CA 95616, USA
| | - Olga Vafaeva
- Department of Ophthalmology & Vision Science, University of California Davis Eye Center, 4860 Y Street, Suite 2400, Sacramento, CA 95817, USA
| | - Christian Dolf
- Department of Ophthalmology & Vision Science, University of California Davis Eye Center, 4860 Y Street, Suite 2400, Sacramento, CA 95817, USA
| | - Yanhong Ma
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, 116024, China
| | - Guozhen Wang
- School of Optoelectronic Engineering and Instrumentation Science, Dalian University of Technology, Dalian, 116024, China
| | - Jessicca Cho
- UC Davis EyePod Small Animals Ocular Imaging Laboratory, University of California Davis, Davis, CA 95616, USA
| | - Henry Ho-Lung Chan
- Laboratory of Experimental Optometry (Neuroscience), School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
- Research Centre for SHARP Vision (RCSV), The Hong Kong Polytechnic University, Hong Kong, China
| | - Nicholas Marsh-Armstrong
- Department of Ophthalmology & Vision Science, University of California Davis Eye Center, 4860 Y Street, Suite 2400, Sacramento, CA 95817, USA
| | - Robert J Zawadzki
- UC Davis EyePod Small Animals Ocular Imaging Laboratory, University of California Davis, Davis, CA 95616, USA
- Center for Human Ocular Imaging Research (CHOIR), Dept. of Ophthalmology & Vision Science, University of California Davis, 4860 Y Street, Suite 2400, Sacramento, CA 95817, USA
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3
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Paşcalău R, Badea TC. Signaling - transcription interactions in mouse retinal ganglion cells early axon pathfinding -a literature review. FRONTIERS IN OPHTHALMOLOGY 2023; 3:1180142. [PMID: 38983012 PMCID: PMC11182120 DOI: 10.3389/fopht.2023.1180142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2023] [Accepted: 04/21/2023] [Indexed: 07/11/2024]
Abstract
Sending an axon out of the eye and into the target brain nuclei is the defining feature of retinal ganglion cells (RGCs). The literature on RGC axon pathfinding is vast, but it focuses mostly on decision making events such as midline crossing at the optic chiasm or retinotopic mapping at the target nuclei. In comparison, the exit of RGC axons out of the eye is much less explored. The first checkpoint on the RGC axons' path is the optic cup - optic stalk junction (OC-OS). OC-OS development and the exit of the RGC pioneer axons out of the eye are coordinated spatially and temporally. By the time the optic nerve head domain is specified, the optic fissure margins are in contact and the fusion process is ongoing, the first RGCs are born in its proximity and send pioneer axons in the optic stalk. RGC differentiation continues in centrifugal waves. Later born RGC axons fasciculate with the more mature axons. Growth cones at the end of the axons respond to guidance cues to adopt a centripetal direction, maintain nerve fiber layer restriction and to leave the optic cup. Although there is extensive information on OC-OS development, we still have important unanswered questions regarding its contribution to the exit of the RGC axons out of the eye. We are still to distinguish the morphogens of the OC-OS from the axon guidance molecules which are expressed in the same place at the same time. The early RGC transcription programs responsible for axon emergence and pathfinding are also unknown. This review summarizes the molecular mechanisms for early RGC axon guidance by contextualizing mouse knock-out studies on OC-OS development with the recent transcriptomic studies on developing RGCs in an attempt to contribute to the understanding of human optic nerve developmental anomalies. The published data summarized here suggests that the developing optic nerve head provides a physical channel (the closing optic fissure) as well as molecular guidance cues for the pioneer RGC axons to exit the eye.
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Affiliation(s)
- Raluca Paşcalău
- Research and Development Institute, Transilvania University of Braşov, Braşov, Romania
- Ophthalmology Clinic, Cluj County Emergency Hospital, Cluj-Napoca, Romania
| | - Tudor Constantin Badea
- Research and Development Institute, Transilvania University of Braşov, Braşov, Romania
- National Center for Brain Research, Institutul de Cercetări pentru Inteligență Artificială, Romanian Academy, Bucharest, Romania
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4
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Chen J, Huang L, Yang Y, Xu W, Qin Q, Qin R, Liang X, Lai X, Huang X, Xie M, Chen L. Somatic Cell Reprogramming for Nervous System Diseases: Techniques, Mechanisms, Potential Applications, and Challenges. Brain Sci 2023; 13:brainsci13030524. [PMID: 36979334 PMCID: PMC10046178 DOI: 10.3390/brainsci13030524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 03/14/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
Nervous system diseases present significant challenges to the neuroscience community due to ethical and practical constraints that limit access to appropriate research materials. Somatic cell reprogramming has been proposed as a novel way to obtain neurons. Various emerging techniques have been used to reprogram mature and differentiated cells into neurons. This review provides an overview of somatic cell reprogramming for neurological research and therapy, focusing on neural reprogramming and generating different neural cell types. We examine the mechanisms involved in reprogramming and the challenges that arise. We herein summarize cell reprogramming strategies to generate neurons, including transcription factors, small molecules, and microRNAs, with a focus on different types of cells.. While reprogramming somatic cells into neurons holds the potential for understanding neurological diseases and developing therapeutic applications, its limitations and risks must be carefully considered. Here, we highlight the potential benefits of somatic cell reprogramming for neurological disease research and therapy. This review contributes to the field by providing a comprehensive overview of the various techniques used to generate neurons by cellular reprogramming and discussing their potential applications.
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Affiliation(s)
- Jiafeng Chen
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Lijuan Huang
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Yue Yang
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Wei Xu
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Qingchun Qin
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Rongxing Qin
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Xiaojun Liang
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Xinyu Lai
- Key Laboratory of Longevity and Aging-Related Diseases of Chinese Ministry of Education, Nanning 530021, China
| | - Xiaoying Huang
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Minshan Xie
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
| | - Li Chen
- Department of Neurology, the First Affiliated Hospital of Guangxi Medical University, Nanning 530021, China
- Key Laboratory of Longevity and Aging-Related Diseases of Chinese Ministry of Education, Nanning 530021, China
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5
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Nadal-Nicolás FM, Galindo-Romero C, Lucas-Ruiz F, Marsh-Amstrong N, Li W, Vidal-Sanz M, Agudo-Barriuso M. Pan-retinal ganglion cell markers in mice, rats, and rhesus macaques. Zool Res 2023; 44:226-248. [PMID: 36594396 PMCID: PMC9841181 DOI: 10.24272/j.issn.2095-8137.2022.308] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Univocal identification of retinal ganglion cells (RGCs) is an essential prerequisite for studying their degeneration and neuroprotection. Before the advent of phenotypic markers, RGCs were normally identified using retrograde tracing of retinorecipient areas. This is an invasive technique, and its use is precluded in higher mammals such as monkeys. In the past decade, several RGC markers have been described. Here, we reviewed and analyzed the specificity of nine markers used to identify all or most RGCs, i.e., pan-RGC markers, in rats, mice, and macaques. The best markers in the three species in terms of specificity, proportion of RGCs labeled, and indicators of viability were BRN3A, expressed by vision-forming RGCs, and RBPMS, expressed by vision- and non-vision-forming RGCs. NEUN, often used to identify RGCs, was expressed by non-RGCs in the ganglion cell layer, and therefore was not RGC-specific. γ-SYN, TUJ1, and NF-L labeled the RGC axons, which impaired the detection of their somas in the central retina but would be good for studying RGC morphology. In rats, TUJ1 and NF-L were also expressed by non-RGCs. BM88, ERRβ, and PGP9.5 are rarely used as markers, but they identified most RGCs in the rats and macaques and ERRβ in mice. However, PGP9.5 was also expressed by non-RGCs in rats and macaques and BM88 and ERRβ were not suitable markers of viability.
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Affiliation(s)
- Francisco M Nadal-Nicolás
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria Pascual Parrilla (IMIB), Murcia 30120, Spain
- Dpto. Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia 30120, Spain
- Retinal Neurophysiology Section, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892-2510, USA
| | - Caridad Galindo-Romero
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria Pascual Parrilla (IMIB), Murcia 30120, Spain
- Dpto. Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia 30120, Spain
| | - Fernando Lucas-Ruiz
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria Pascual Parrilla (IMIB), Murcia 30120, Spain
- Dpto. Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia 30120, Spain
| | - Nicholas Marsh-Amstrong
- Department of Ophthalmology and Vision Science, University of California, Davis, CA 95817, USA
| | - Wei Li
- Retinal Neurophysiology Section, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892-2510, USA
| | - Manuel Vidal-Sanz
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria Pascual Parrilla (IMIB), Murcia 30120, Spain
- Dpto. Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia 30120, Spain. E-mail:
| | - Marta Agudo-Barriuso
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria Pascual Parrilla (IMIB), Murcia 30120, Spain
- Dpto. Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia 30120, Spain. E-mail:
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6
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A cell-ECM mechanism for connecting the ipsilateral eye to the brain. Proc Natl Acad Sci U S A 2021; 118:2104343118. [PMID: 34654745 PMCID: PMC8545493 DOI: 10.1073/pnas.2104343118] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/24/2021] [Indexed: 12/11/2022] Open
Abstract
Distinct features of the visual world are transmitted from the retina to the brain through anatomically segregated circuits. Despite this being an organizing principle of visual pathways in mammals, we lack an understanding of the signaling mechanisms guiding axons of different types of retinal neurons into segregated layers of brain regions. We explore this question by identifying how axons from the ipsilateral retina innervate a specific lamina of the superior colliculus. Our studies reveal a unique cell–extracellular matrix recognition mechanism that specifies precise targeting of these axons to the superior colliculus. Loss of this mechanism not only resulted in the absence of this eye-specific visual circuit, but it led to an impairment of innate predatory visual behavior as well. Information about features in the visual world is parsed by circuits in the retina and is then transmitted to the brain by distinct subtypes of retinal ganglion cells (RGCs). Axons from RGC subtypes are stratified in retinorecipient brain nuclei, such as the superior colliculus (SC), to provide a segregated relay of parallel and feature-specific visual streams. Here, we sought to identify the molecular mechanisms that direct the stereotyped laminar targeting of these axons. We focused on ipsilateral-projecting subtypes of RGCs (ipsiRGCs) whose axons target a deep SC sublamina. We identified an extracellular glycoprotein, Nephronectin (NPNT), whose expression is restricted to this ipsiRGC-targeted sublamina. SC-derived NPNT and integrin receptors expressed by ipsiRGCs are both required for the targeting of ipsiRGC axons to the deep sublamina of SC. Thus, a cell–extracellular matrix (ECM) recognition mechanism specifies precise laminar targeting of ipsiRGC axons and the assembly of eye-specific parallel visual pathways.
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Johnson KO, Triplett JW. Wiring subcortical image-forming centers: Topography, laminar targeting, and map alignment. Curr Top Dev Biol 2020; 142:283-317. [PMID: 33706920 DOI: 10.1016/bs.ctdb.2020.10.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Efficient sensory processing is a complex and important function for species survival. As such, sensory circuits are highly organized to facilitate rapid detection of salient stimuli and initiate motor responses. For decades, the retina's projections to image-forming centers have served as useful models to elucidate the mechanisms by which such exquisite circuitry is wired. In this chapter, we review the roles of molecular cues, neuronal activity, and axon-axon competition in the development of topographically ordered retinal ganglion cell (RGC) projections to the superior colliculus (SC) and dorsal lateral geniculate nucleus (dLGN). Further, we discuss our current state of understanding regarding the laminar-specific targeting of subclasses of RGCs in the SC and its homolog, the optic tectum (OT). Finally, we cover recent studies examining the alignment of projections from primary visual cortex with RGCs that monitor the same region of space in the SC.
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Affiliation(s)
- Kristy O Johnson
- Center for Neuroscience Research, Children's National Research Institute, Washington, DC, United States; Institute for Biomedical Sciences, The George Washington University School of Medicine, Washington, DC, United States
| | - Jason W Triplett
- Center for Neuroscience Research, Children's National Research Institute, Washington, DC, United States; Department of Pediatrics, The George Washington University School of Medicine, Washington, DC, United States.
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8
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Disruption of Critical Period Plasticity in a Mouse Model of Neurofibromatosis Type 1. J Neurosci 2020; 40:5495-5509. [PMID: 32527982 DOI: 10.1523/jneurosci.2235-19.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 05/04/2020] [Accepted: 05/07/2020] [Indexed: 11/21/2022] Open
Abstract
Neurofibromatosis type 1 (NF1) is a common monogenic neurodevelopmental disorder associated with physical and cognitive problems. The cognitive issues are thought to arise from increased release of the neurotransmitter GABA. Modulating the signaling pathways causing increased GABA release in a mouse model of NF1 reverts deficits in hippocampal learning. However, clinical trials based on these approaches have so far been unsuccessful. We therefore used a combination of slice electrophysiology, in vivo two-photon calcium imaging, and optical imaging of intrinsic signal in a mouse model of NF1 to investigate whether cortical development is affected in NF1, possibly causing lifelong consequences that cannot be rescued by reducing inhibition later in life. We find that, in NF1 mice of both sexes, inhibition increases strongly during the development of the visual cortex and remains high. While this increase in cortical inhibition does not affect spontaneous cortical activity patterns during early cortical development, the critical period for ocular dominance plasticity is shortened in NF1 mice due to its early closure but unaltered onset. Notably, after environmental enrichment, differences in inhibitory innervation and ocular dominance plasticity between NF1 mice and WT littermates disappear. These results provide the first evidence for critical period dysregulation in NF1 and suggest that treatments aimed at normalizing levels of inhibition will need to start at early stages of development.SIGNIFICANCE STATEMENT Neurofibromatosis type 1 is associated with cognitive problems for which no treatment is currently available. This study shows that, in a mouse model of neurofibromatosis type 1, cortical inhibition is increased during development and critical period regulation is disturbed. Rearing the mice in an environment that stimulates cognitive function overcomes these deficits. These results uncover critical period dysregulation as a novel mechanism in the pathogenesis of neurofibromatosis type 1. This suggests that targeting the affected signaling pathways in neurofibromatosis type 1 for the treatment of cognitive disabilities may have to start at a much younger age than has so far been tested in clinical trials.
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9
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Lu Y, Shiau F, Yi W, Lu S, Wu Q, Pearson JD, Kallman A, Zhong S, Hoang T, Zuo Z, Zhao F, Zhang M, Tsai N, Zhuo Y, He S, Zhang J, Stein-O'Brien GL, Sherman TD, Duan X, Fertig EJ, Goff LA, Zack DJ, Handa JT, Xue T, Bremner R, Blackshaw S, Wang X, Clark BS. Single-Cell Analysis of Human Retina Identifies Evolutionarily Conserved and Species-Specific Mechanisms Controlling Development. Dev Cell 2020; 53:473-491.e9. [PMID: 32386599 PMCID: PMC8015270 DOI: 10.1016/j.devcel.2020.04.009] [Citation(s) in RCA: 147] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/05/2020] [Accepted: 04/10/2020] [Indexed: 01/08/2023]
Abstract
The development of single-cell RNA sequencing (scRNA-seq) has allowed high-resolution analysis of cell-type diversity and transcriptional networks controlling cell-fate specification. To identify the transcriptional networks governing human retinal development, we performed scRNA-seq analysis on 16 time points from developing retina as well as four early stages of retinal organoid differentiation. We identified evolutionarily conserved patterns of gene expression during retinal progenitor maturation and specification of all seven major retinal cell types. Furthermore, we identified gene-expression differences between developing macula and periphery and between distinct populations of horizontal cells. We also identified species-specific patterns of gene expression during human and mouse retinal development. Finally, we identified an unexpected role for ATOH7 expression in regulation of photoreceptor specification during late retinogenesis. These results provide a roadmap to future studies of human retinal development and may help guide the design of cell-based therapies for treating retinal dystrophies.
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Affiliation(s)
- Yufeng Lu
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fion Shiau
- John F. Hardesty, MD, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Wenyang Yi
- Hefei National Laboratory for Physical Sciences, at the Microscale, Neurodegenerative Disorder Research Center, CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, University of Science and Technology of China, Hefei 230026, China
| | - Suying Lu
- Lunenfeld Tanenbaum Research Institute, Mt Sinai Hospital, Sinai Health Systems, Department of Ophthalmology and Vision Science, and Department of Lab Medicine and Pathobiology, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Qian Wu
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Joel D Pearson
- Lunenfeld Tanenbaum Research Institute, Mt Sinai Hospital, Sinai Health Systems, Department of Ophthalmology and Vision Science, and Department of Lab Medicine and Pathobiology, University of Toronto, Toronto, ON M5G 1X5, Canada
| | - Alyssa Kallman
- Department of Ophthalmology, Wilmer Eye Institute Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Suijuan Zhong
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Thanh Hoang
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Zhentao Zuo
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Fangqi Zhao
- Obstetrics and Gynecology Medical Center of Severe Cardiovascular of Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Mei Zhang
- Hefei National Laboratory for Physical Sciences, at the Microscale, Neurodegenerative Disorder Research Center, CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, University of Science and Technology of China, Hefei 230026, China; CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Nicole Tsai
- Departments of Ophthalmology and Physiology, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Yan Zhuo
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Sheng He
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Jun Zhang
- Obstetrics and Gynecology Medical Center of Severe Cardiovascular of Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Genevieve L Stein-O'Brien
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Thomas D Sherman
- Department of Oncology, Division of Biostatistics and Bioinformatics, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Xin Duan
- Departments of Ophthalmology and Physiology, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Elana J Fertig
- Department of Oncology, Division of Biostatistics and Bioinformatics, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; McKusick-Nathans Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Institute for Data Intensive Engineering and Science, Johns Hopkins University, Baltimore, MD 21218, USA; Institute for Computational Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Mathematical Institute for Data Science, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Applied Mathematics and Statistics, Johns Hopkins University, Baltimore, MD 21218, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Loyal A Goff
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; McKusick-Nathans Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Donald J Zack
- Department of Ophthalmology, Wilmer Eye Institute Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; McKusick-Nathans Institute for Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - James T Handa
- Department of Ophthalmology, Wilmer Eye Institute Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Tian Xue
- Hefei National Laboratory for Physical Sciences, at the Microscale, Neurodegenerative Disorder Research Center, CAS Key Laboratory of Brain Function and Disease, School of Life Sciences, University of Science and Technology of China, Hefei 230026, China; CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China.
| | - Rod Bremner
- Lunenfeld Tanenbaum Research Institute, Mt Sinai Hospital, Sinai Health Systems, Department of Ophthalmology and Vision Science, and Department of Lab Medicine and Pathobiology, University of Toronto, Toronto, ON M5G 1X5, Canada.
| | - Seth Blackshaw
- Department of Ophthalmology, Wilmer Eye Institute Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD 21218, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Center for Human Systems Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Xiaoqun Wang
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China; Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing 100101, China; Beijing Institute for Brain Disorders, Beijing 100069, China.
| | - Brian S Clark
- John F. Hardesty, MD, Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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10
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Abstract
Binocular vision depends on retinal ganglion cell (RGC) axon projection either to the same side or to the opposite side of the brain. In this article, we review the molecular mechanisms for decussation of RGC axons, with a focus on axon guidance signaling at the optic chiasm and ipsi- and contralateral axon organization in the optic tract prior to and during targeting. The spatial and temporal features of RGC neurogenesis that give rise to ipsilateral and contralateral identity are described. The albino visual system is highlighted as an apt comparative model for understanding RGC decussation, as albinos have a reduced ipsilateral projection and altered RGC neurogenesis associated with perturbed melanogenesis in the retinal pigment epithelium. Understanding the steps for RGC specification into ipsi- and contralateral subtypes will facilitate differentiation of stem cells into RGCs with proper navigational abilities for effective axon regeneration and correct targeting of higher-order visual centers.
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Affiliation(s)
- Carol Mason
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10027, USA; .,Department of Neuroscience, Columbia University, New York, NY 10027, USA.,Department of Ophthalmology, Columbia University, New York, NY 10027, USA.,Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA;
| | - Nefeli Slavi
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA;
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11
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Neuroprotective Strategies for Retinal Ganglion Cell Degeneration: Current Status and Challenges Ahead. Int J Mol Sci 2020; 21:ijms21072262. [PMID: 32218163 PMCID: PMC7177277 DOI: 10.3390/ijms21072262] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/19/2020] [Accepted: 03/20/2020] [Indexed: 12/12/2022] Open
Abstract
The retinal ganglion cells (RGCs) are the output cells of the retina into the brain. In mammals, these cells are not able to regenerate their axons after optic nerve injury, leaving the patients with optic neuropathies with permanent visual loss. An effective RGCs-directed therapy could provide a beneficial effect to prevent the progression of the disease. Axonal injury leads to the functional loss of RGCs and subsequently induces neuronal death, and axonal regeneration would be essential to restore the neuronal connectivity, and to reestablish the function of the visual system. The manipulation of several intrinsic and extrinsic factors has been proposed in order to stimulate axonal regeneration and functional repairing of axonal connections in the visual pathway. However, there is a missing point in the process since, until now, there is no therapeutic strategy directed to promote axonal regeneration of RGCs as a therapeutic approach for optic neuropathies.
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12
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Nguyen-Ba-Charvet KT, Rebsam A. Neurogenesis and Specification of Retinal Ganglion Cells. Int J Mol Sci 2020; 21:ijms21020451. [PMID: 31936811 PMCID: PMC7014133 DOI: 10.3390/ijms21020451] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 01/07/2020] [Accepted: 01/08/2020] [Indexed: 12/25/2022] Open
Abstract
Across all species, retinal ganglion cells (RGCs) are the first retinal neurons generated during development, followed by the other retinal cell types. How are retinal progenitor cells (RPCs) able to produce these cell types in a specific and timely order? Here, we will review the different models of retinal neurogenesis proposed over the last decades as well as the extrinsic and intrinsic factors controlling it. We will then focus on the molecular mechanisms, especially the cascade of transcription factors that regulate, more specifically, RGC fate. We will also comment on the recent discovery that the ciliary marginal zone is a new stem cell niche in mice contributing to retinal neurogenesis, especially to the generation of ipsilateral RGCs. Furthermore, RGCs are composed of many different subtypes that are anatomically, physiologically, functionally, and molecularly defined. We will summarize the different classifications of RGC subtypes and will recapitulate the specification of some of them and describe how a genetic disease such as albinism affects neurogenesis, resulting in profound visual deficits.
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13
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Whyland KL, Slusarczyk AS, Bickford ME. GABAergic cell types in the superficial layers of the mouse superior colliculus. J Comp Neurol 2019; 528:308-320. [PMID: 31396959 DOI: 10.1002/cne.24754] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 08/02/2019] [Accepted: 08/02/2019] [Indexed: 12/20/2022]
Abstract
To begin to unravel the complexities of GABAergic circuits in the superior colliculus (SC), we utilized mouse lines that express green fluorescent protein (GFP) in cells that contain the 67 kDa isoform of glutamic acid decarboxylase (GAD67-GFP), or Cre-recombinase in cells that contain glutamic acid decarboxylase (GAD; GAD2-cre). We used Cre-dependent virus injections in GAD2-Cre mice and tracer injections in GAD67-GFP mice, as well as immunocytochemical staining for gamma amino butyric acid (GABA) and parvalbumin (PV) to characterize GABAergic cells that project to the pretectum (PT), ventral lateral geniculate nucleus (vLGN) or parabigeminal nucleus (PBG), and interneurons in the stratum griseum superficiale (SGS) that do not project outside the SC. We found that approximately 30% of SGS neurons in the mouse are GABAergic. Of these GABAergic neurons, we identified three categories of potential interneurons in the GAD67-GFP line (GABA+GFP ~45%, GABA+GFP + PV ~15%, and GABA+PV ~10%). GABAergic cells that did not contain GFP or PV were identified as potential projection neurons (GABA only ~30%). We found that GABAergic neurons that project to the PBG are primarily located in the SGS and exhibit narrow field vertical, stellate, and horizontal dendritic morphologies, while GABAergic neurons that project to the PT and vLGN are primarily located in layers ventral to the SGS. In addition, we examined GABA and GAD67-containing elements of the mouse SGS using electron microscopy to further delineate the relationship between GABAergic circuits and retinotectal input. Approximately 30% of retinotectal synaptic targets are the presynaptic dendrites of GABAergic interneurons, and GAD67-GFP interneurons are a source of these presynaptic dendrites.
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Affiliation(s)
- Kyle L Whyland
- Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky
| | | | - Martha E Bickford
- Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky
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14
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Effect of ocular hypertension on the pattern of retinal ganglion cell subtype loss in a mouse model of early-onset glaucoma. Exp Eye Res 2019; 185:107703. [PMID: 31211954 PMCID: PMC7430001 DOI: 10.1016/j.exer.2019.107703] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 06/06/2019] [Accepted: 06/15/2019] [Indexed: 12/16/2022]
Abstract
Glaucoma is a neurodegenerative disease with elevated intraocular pressure as one of the major risk factors. Glaucoma leads to irreversible loss of vision and its progression involves optic nerve head cupping, axonal degeneration, retinal ganglion cell (RGC) loss, and visual field defects. Despite its high global prevalence, glaucoma still remains a major neurodegenerative disease. Introduction of mouse models of experimental glaucoma has become integral to glaucoma research due to well-studied genetics as well as ease of manipulations. Many established inherent and inducible mouse models of glaucoma are used to study the molecular and physiological progression of the disease. One such model of spontaneous mutation is the nee model, which is caused by mutation of the Sh3pxd2b gene. In both humans and mice, mutations disrupting function of the SH3PXD2B adaptor protein cause a developmental syndrome including secondary congenital glaucoma. The purpose of this study was to characterize the early onset nee glaucoma phenotype on the C57BL/6J background and to evaluate the pattern of RGC loss and axonal degeneration in specific RGC subtypes. We found that the B6.Sh3pxd2bnee mutant animals exhibit glaucoma phenotypes of elevated intraocular pressure, RGC loss and axonal degeneration. Moreover, the non-image forming RGCs survived longer than the On-Off direction selective RGCs (DSGC), and the axonal death in these RGCs was independent of their respective RGC subtype. In conclusion, through this study we characterized an experimental model of early onset glaucoma on a C57BL/6J background exhibiting key glaucoma phenotypes. In addition, we describe that RGC death has subtype-specific sensitivities and follows a specific pattern of cell death under glaucomatous conditions.
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15
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Murcia-Belmonte V, Erskine L. Wiring the Binocular Visual Pathways. Int J Mol Sci 2019; 20:ijms20133282. [PMID: 31277365 PMCID: PMC6651880 DOI: 10.3390/ijms20133282] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 06/29/2019] [Accepted: 07/03/2019] [Indexed: 02/06/2023] Open
Abstract
Retinal ganglion cells (RGCs) extend axons out of the retina to transmit visual information to the brain. These connections are established during development through the navigation of RGC axons along a relatively long, stereotypical pathway. RGC axons exit the eye at the optic disc and extend along the optic nerves to the ventral midline of the brain, where the two nerves meet to form the optic chiasm. In animals with binocular vision, the axons face a choice at the optic chiasm—to cross the midline and project to targets on the contralateral side of the brain, or avoid crossing the midline and project to ipsilateral brain targets. Ipsilaterally and contralaterally projecting RGCs originate in disparate regions of the retina that relate to the extent of binocular overlap in the visual field. In humans virtually all RGC axons originating in temporal retina project ipsilaterally, whereas in mice, ipsilaterally projecting RGCs are confined to the peripheral ventrotemporal retina. This review will discuss recent advances in our understanding of the mechanisms regulating specification of ipsilateral versus contralateral RGCs, and the differential guidance of their axons at the optic chiasm. Recent insights into the establishment of congruent topographic maps in both brain hemispheres also will be discussed.
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Affiliation(s)
| | - Lynda Erskine
- School of Medicine, Medical Sciences and Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, Scotland AB25 2ZD, UK
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16
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Miltner AM, Mercado-Ayon Y, Cheema SK, Zhang P, Zawadzki RJ, La Torre A. A Novel Reporter Mouse Uncovers Endogenous Brn3b Expression. Int J Mol Sci 2019; 20:E2903. [PMID: 31197108 PMCID: PMC6627301 DOI: 10.3390/ijms20122903] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/11/2019] [Accepted: 06/12/2019] [Indexed: 12/18/2022] Open
Abstract
Brn3b (Pou4f2) is a class-4 POU domain transcription factor known to play central roles in the development of different neuronal populations of the Central Nervous System, including retinal ganglion cells (RGCs), the neurons that connect the retina with the visual centers of the brain. Here, we have used CRISPR-based genetic engineering to generate a Brn3b-mCherry reporter mouse without altering the endogenous expression of Brn3b. In our mouse line, mCherry faithfully recapitulates normal Brn3b expression in the retina, the optic tracts, the midbrain tectum, and the trigeminal ganglia. The high sensitivity of mCherry also revealed novel expression of Brn3b in the neuroectodermal cells of the optic stalk during early stages of eye development. Importantly, the fluorescent intensity of Brn3b-mCherry in our reporter mice allows for noninvasive live imaging of RGCs using Scanning Laser Ophthalmoscopy (SLO), providing a novel tool for longitudinal monitoring of RGCs.
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Affiliation(s)
- Adam M Miltner
- Department of Cell Biology and Human Anatomy, University of California-Davis, Davis, CA 95616, USA.
| | - Yesica Mercado-Ayon
- Department of Cell Biology and Human Anatomy, University of California-Davis, Davis, CA 95616, USA.
| | - Simranjeet K Cheema
- Department of Cell Biology and Human Anatomy, University of California-Davis, Davis, CA 95616, USA.
| | - Pengfei Zhang
- Department of Cell Biology and Human Anatomy, University of California-Davis, Davis, CA 95616, USA.
- UC Davis EyePod Small Animal Ocular Imaging Laboratory, University of California-Davis, Davis, CA 95616, USA.
| | - Robert J Zawadzki
- UC Davis EyePod Small Animal Ocular Imaging Laboratory, University of California-Davis, Davis, CA 95616, USA.
- Department of Ophthalmology and Vision Science, University of California-Davis, Sacramento, CA 95817, USA.
| | - Anna La Torre
- Department of Cell Biology and Human Anatomy, University of California-Davis, Davis, CA 95616, USA.
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17
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Kiyama T, Long Y, Chen CK, Whitaker CM, Shay A, Wu H, Badea TC, Mohsenin A, Parker-Thornburg J, Klein WH, Mills SL, Massey SC, Mao CA. Essential Roles of Tbr1 in the Formation and Maintenance of the Orientation-Selective J-RGCs and a Group of OFF-Sustained RGCs in Mouse. Cell Rep 2019; 27:900-915.e5. [PMID: 30995485 PMCID: PMC6542366 DOI: 10.1016/j.celrep.2019.03.077] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 02/10/2019] [Accepted: 03/20/2019] [Indexed: 01/27/2023] Open
Abstract
In the mouse retina, more than 30 retinal ganglion cell (RGC) subtypes have been classified based on a combined metric of morphological and functional characteristics. RGCs arise from a common pool of retinal progenitor cells during embryonic stages and differentiate into mature subtypes in adult retinas. However, the cellular and molecular mechanisms controlling formation and maturation of such remarkable cellular diversity remain unknown. Here, we demonstrate that T-box transcription factor T-brain 1 (Tbr1) is expressed in two groups of morphologically and functionally distinct RGCs: the orientation-selective J-RGCs and a group of OFF-sustained RGCs with symmetrical dendritic arbors. When Tbr1 is genetically ablated during retinal development, these two RGC groups cannot develop. Ectopically expressing Tbr1 in M4 ipRGCs during development alters dendritic branching and density but not the inner plexiform layer stratification level. Our data indicate that Tbr1 plays critical roles in regulating the formation and dendritic morphogenesis of specific RGC types.
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Affiliation(s)
- Takae Kiyama
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Ye Long
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Ching-Kang Chen
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Christopher M Whitaker
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Allison Shay
- Department of Ophthalmology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hongyu Wu
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Tudor C Badea
- National Eye Institute, NIH, Bethesda, MD 20892, USA
| | - Amir Mohsenin
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA; Robert Cizik Eye Clinic, Houston, TX 77030, USA
| | - Jan Parker-Thornburg
- Department of Genetics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - William H Klein
- Department of Systems Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Stephen L Mills
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Stephen C Massey
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA
| | - Chai-An Mao
- Ruiz Department of Ophthalmology and Visual Science, McGovern Medical School at The University of Texas Health Science Center at Houston (UTHealth), Houston, TX 77030, USA.
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18
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GABA release selectively regulates synapse development at distinct inputs on direction-selective retinal ganglion cells. Proc Natl Acad Sci U S A 2018; 115:E12083-E12090. [PMID: 30509993 DOI: 10.1073/pnas.1803490115] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Synaptic inhibition controls a neuron's output via functionally distinct inputs at two subcellular compartments, the cell body and the dendrites. It is unclear whether the assembly of these distinct inhibitory inputs can be regulated independently by neurotransmission. In the mammalian retina, γ-aminobutyric acid (GABA) release from starburst amacrine cells (SACs) onto the dendrites of on-off direction-selective ganglion cells (ooDSGCs) is essential for directionally selective responses. We found that ooDSGCs also receive GABAergic input on their somata from other amacrine cells (ACs), including ACs containing the vasoactive intestinal peptide (VIP). When net GABAergic transmission is reduced, somatic, but not dendritic, GABAA receptor clusters on the ooDSGC increased in number and size. Correlative fluorescence imaging and serial electron microscopy revealed that these enlarged somatic receptor clusters are localized to synapses. By contrast, selectively blocking vesicular GABA release from either SACs or VIP ACs did not alter dendritic or somatic receptor distributions on the ooDSGCs, showing that neither SAC nor VIP AC GABA release alone is required for the development of inhibitory synapses in ooDSGCs. Furthermore, a reduction in net GABAergic transmission, but not a selective reduction from SACs, increased excitatory drive onto ooDSGCs. This increased excitation may drive a homeostatic increase in ooDSGC somatic GABAA receptors. Differential regulation of GABAA receptors on the ooDSGC's soma and dendrites could facilitate homeostatic control of the ooDSGC's output while enabling the assembly of the GABAergic connectivity underlying direction selectivity to be indifferent to altered transmission.
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19
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Cang J, Savier E, Barchini J, Liu X. Visual Function, Organization, and Development of the Mouse Superior Colliculus. Annu Rev Vis Sci 2018; 4:239-262. [PMID: 29852095 DOI: 10.1146/annurev-vision-091517-034142] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The superior colliculus (SC) is the most prominent visual center in mice. Studies over the past decade have greatly advanced our understanding of the function, organization, and development of the mouse SC, which has rapidly become a popular model in vision research. These studies have described the diverse and cell-type-specific visual response properties in the mouse SC, revealed their laminar and topographic organizations, and linked the mouse SC and downstream pathways with visually guided behaviors. Here, we summarize these findings, compare them with the rich literature of SC studies in other species, and highlight important gaps and exciting future directions. Given its clear importance in mouse vision and the available modern neuroscience tools, the mouse SC holds great promise for understanding the cellular, circuit, and developmental mechanisms that underlie visual processing, sensorimotor transformation, and, ultimately, behavior.
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Affiliation(s)
- Jianhua Cang
- Department of Biology and Department of Psychology, University of Virginia, Charlottesville, Virginia 22904, USA;
| | - Elise Savier
- Department of Biology and Department of Psychology, University of Virginia, Charlottesville, Virginia 22904, USA;
| | - Jad Barchini
- Department of Functional Architecture and Development of Cerebral Cortex, Max Planck Florida Institute for Neuroscience, Jupiter, Florida 33458, USA
| | - Xiaorong Liu
- Department of Biology and Department of Psychology, University of Virginia, Charlottesville, Virginia 22904, USA;
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20
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Langer KB, Ohlemacher SK, Phillips MJ, Fligor CM, Jiang P, Gamm DM, Meyer JS. Retinal Ganglion Cell Diversity and Subtype Specification from Human Pluripotent Stem Cells. Stem Cell Reports 2018; 10:1282-1293. [PMID: 29576537 PMCID: PMC5998302 DOI: 10.1016/j.stemcr.2018.02.010] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 02/20/2018] [Accepted: 02/21/2018] [Indexed: 12/01/2022] Open
Abstract
Retinal ganglion cells (RGCs) are the projection neurons of the retina and transmit visual information to postsynaptic targets in the brain. While this function is shared among nearly all RGCs, this class of cell is remarkably diverse, comprised of multiple subtypes. Previous efforts have identified numerous RGC subtypes in animal models, but less attention has been paid to human RGCs. Thus, efforts of this study examined the diversity of RGCs differentiated from human pluripotent stem cells (hPSCs) and characterized defined subtypes through the expression of subtype-specific markers. Further investigation of these subtypes was achieved using single-cell transcriptomics, confirming the combinatorial expression of molecular markers associated with these subtypes, and also provided insight into more subtype-specific markers. Thus, the results of this study describe the derivation of RGC subtypes from hPSCs and will support the future exploration of phenotypic and functional diversity within human RGCs. Unique transcriptional profiles demonstrate diversity among hPSC-derived RGCs Numerous RGC subtypes characterized from hPSC-derived RGCs Molecular markers identified for RGC subtypes through single-cell RNA-seq analysis
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Affiliation(s)
- Kirstin B Langer
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN 46202, USA
| | - Sarah K Ohlemacher
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN 46202, USA
| | - M Joseph Phillips
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Clarisse M Fligor
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN 46202, USA
| | - Peng Jiang
- Morgridge Institute for Research, Madison, WI 53705, USA
| | - David M Gamm
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA; McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI 53705, USA; Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Jason S Meyer
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN 46202, USA; Department of Medical and Molecular Genetics, Indiana University, Indianapolis, IN 46202, USA; Stark Neurosciences Research Institute, Indiana University, Indianapolis, IN 46202, USA.
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21
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Guidance of retinal axons in mammals. Semin Cell Dev Biol 2017; 85:48-59. [PMID: 29174916 DOI: 10.1016/j.semcdb.2017.11.027] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Revised: 11/17/2017] [Accepted: 11/20/2017] [Indexed: 11/21/2022]
Abstract
In order to navigate through the surrounding environment many mammals, including humans, primarily rely on vision. The eye, composed of the choroid, sclera, retinal pigmented epithelium, cornea, lens, iris and retina, is the structure that receives the light and converts it into electrical impulses. The retina contains six major types of neurons involving in receiving and modifying visual information and passing it onto higher visual processing centres in the brain. Visual information is relayed to the brain via the axons of retinal ganglion cells (RGCs), a projection known as the optic pathway. The proper formation of this pathway during development is essential for normal vision in the adult individual. Along this pathway there are several points where visual axons face 'choices' in their direction of growth. Understanding how these choices are made has advanced significantly our knowledge of axon guidance mechanisms. Thus, the development of the visual pathway has served as an extremely useful model to reveal general principles of axon pathfinding throughout the nervous system. However, due to its particularities, some cellular and molecular mechanisms are specific for the visual circuit. Here we review both general and specific mechanisms involved in the guidance of mammalian RGC axons when they are traveling from the retina to the brain to establish precise and stereotyped connections that will sustain vision.
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22
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Freed MA. Asymmetry between ON and OFF α ganglion cells of mouse retina: integration of signal and noise from synaptic inputs. J Physiol 2017; 595:6979-6991. [PMID: 28913831 PMCID: PMC5685833 DOI: 10.1113/jp274736] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 09/12/2017] [Indexed: 01/12/2023] Open
Abstract
KEY POINTS Bipolar and amacrine cells presynaptic to the ON sustained α cell of mouse retina provide currents with a higher signal-to-noise power ratio (SNR) than those presynaptic to the OFF sustained α cell. Yet the ON cell loses proportionately more SNR from synaptic inputs to spike output than the OFF cell does. The higher SNR of ON bipolar cells at the beginning of the ON pathway compensates for losses incurred by the ON ganglion cell, and improves the processing of positive contrasts. ABSTRACT ON and OFF pathways in the retina include functional pairs of neurons that, at first glance, appear to have symmetrically similar responses to brightening and darkening, respectively. Upon careful examination, however, functional pairs exhibit asymmetries in receptive field size and response kinetics. Until now, descriptions of how light-adapted retinal circuitry maintains a preponderance of signal over the noise have not distinguished between ON and OFF pathways. Here I present evidence of marked asymmetries between members of a functional pair of sustained α ganglion cells in the mouse retina. The ON cell exhibited a proportionately greater loss of signal-to-noise power ratio (SNR) from its presynaptic arrays to its postsynaptic currents. Thus the ON cell combines signal and noise from its presynaptic arrays of bipolar and amacrine cells less efficiently than the OFF cell does. Yet the inefficiency of the ON cell is compensated by its presynaptic arrays providing a higher SNR than the arrays presynaptic to the OFF cell, apparently to improve visual processing of positive contrasts. Dynamic clamp experiments were performed that introduced synaptic conductances into ON and OFF cells. When the amacrine-modulated conductance was removed, the ON cell's spike train exhibited an increase in SNR. The OFF cell, however, showed the opposite effect of removing amacrine input, which was a decrease in SNR. Thus ON and OFF cells have different modes of synaptic integration with direct effects on the SNR of the spike output.
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Affiliation(s)
- Michael A. Freed
- Department of NeuroscienceUniversity of PennsylvaniaPhiladelphiaPAUSA
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23
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Kay RB, Triplett JW. Visual Neurons in the Superior Colliculus Innervated by Islet2 + or Islet2 - Retinal Ganglion Cells Display Distinct Tuning Properties. Front Neural Circuits 2017; 11:73. [PMID: 29066954 PMCID: PMC5641327 DOI: 10.3389/fncir.2017.00073] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 09/19/2017] [Indexed: 11/20/2022] Open
Abstract
Throughout the visual system, different subtypes of neurons are tuned to distinct aspects of the visual scene, establishing parallel circuits. Defining the mechanisms by which such tuning arises has been a long-standing challenge for neuroscience. To investigate this, we have focused on the retina’s projection to the superior colliculus (SC), where multiple visual neuron subtypes have been described. The SC receives inputs from a variety of retinal ganglion cell (RGC) subtypes; however, which RGCs drive the tuning of different SC neurons remains unclear. Here, we pursued a genetic approach that allowed us to determine the tuning properties of neurons innervated by molecularly defined subpopulations of RGCs. In homozygous Islet2-EphA3 knock-in (Isl2EA3/EA3) mice, Isl2+ and Isl2− RGCs project to non-overlapping sub-regions of the SC. Based on molecular and anatomic data, we show that significantly more Isl2− RGCs are direction-selective (DS) in comparison with Isl2+ RGCs. Targeted recordings of visual responses from each SC sub-region in Isl2EA3/EA3 mice revealed that Isl2− RGC-innervated neurons were significantly more DS than those innervated by Isl2+ RGCs. Axis-selective (AS) neurons were found in both sub-regions, though AS neurons innervated by Isl2+ RGCs were more tightly tuned. Despite this segregation, DS and AS neurons innervated by Isl2+ or Isl2− RGCs did not differ in their spatial summation or spatial frequency (SF) tuning. Further, we did not observe alterations in receptive field (RF) size or structure of SC neurons innervated by Isl2+ or Isl2− RGCs. Together, these data show that innervation by Isl2+ and Isl2− RGCs results in distinct tuning in the SC and set the stage for future studies investigating the mechanisms by which these circuits are built.
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Affiliation(s)
- Rachel B Kay
- Center for Neuroscience Research, Children's National Medical Center, Washington, DC, United States
| | - Jason W Triplett
- Center for Neuroscience Research, Children's National Medical Center, Washington, DC, United States.,Department of Pediatrics, The George Washington University School of Medicine and Health Science, Washington, DC, United States
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Groman-Lupa S, Adewumi J, Park KU, Brzezinski JA. The Transcription Factor Prdm16 Marks a Single Retinal Ganglion Cell Subtype in the Mouse Retina. Invest Ophthalmol Vis Sci 2017; 58:5421-5433. [PMID: 29053761 PMCID: PMC5656415 DOI: 10.1167/iovs.17-22442] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 09/20/2017] [Indexed: 12/04/2022] Open
Abstract
Purpose Retinal ganglion cells (RGC) can be categorized into roughly 30 distinct subtypes. How these subtypes develop is poorly understood, in part because few unique subtype markers have been characterized. We tested whether the Prdm16 transcription factor is expressed by RGCs as a class or within particular ganglion cell subtypes. Methods Embryonic and mature retinal sections and flatmount preparations were examined by immunohistochemistry for Prdm16 and several other cell type-specific markers. To visualize the morphology of Prdm16+ cells, we utilized Thy1-YFP-H transgenic mice, where a small random population of RGCs expresses yellow fluorescent protein (YFP) throughout the cytoplasm. Results Prdm16 was expressed in the retina starting late in embryogenesis. Prdm16+ cells coexpressed the RGC marker Brn3a. These cells were arranged in an evenly spaced pattern and accounted for 2% of all ganglion cells. Prdm16+ cells coexpressed parvalbumin, but not calretinin, melanopsin, Smi32, or CART. This combination of marker expression and morphology data from Thy1-YFP-H mice suggested that the Prdm16+ cells represented a single ganglion cell subtype. Prdm16 also marked vascular endothelial cells and mural cells of retinal arterioles. Conclusions A single subtype of ganglion cell appears to be uniquely marked by Prdm16 expression. While the precise identity of these ganglion cells is unclear, they most resemble the G9 subtype described by Völgyi and colleagues in 2009. Future studies are needed to determine the function of these ganglion cells and whether Prdm16 regulates their development.
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Affiliation(s)
- Sergio Groman-Lupa
- Department of Ophthalmology, University of Colorado Denver, Aurora, Colorado, United States
| | - Joseph Adewumi
- Department of Ophthalmology, University of Colorado Denver, Aurora, Colorado, United States
| | - Ko Uoon Park
- Department of Ophthalmology, University of Colorado Denver, Aurora, Colorado, United States
| | - Joseph A. Brzezinski
- Department of Ophthalmology, University of Colorado Denver, Aurora, Colorado, United States
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Corticothalamic Axons Are Essential for Retinal Ganglion Cell Axon Targeting to the Mouse Dorsal Lateral Geniculate Nucleus. J Neurosci 2017; 36:5252-63. [PMID: 27170123 DOI: 10.1523/jneurosci.4599-15.2016] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 03/25/2016] [Indexed: 01/21/2023] Open
Abstract
UNLABELLED Retinal ganglion cells (RGCs) relay information about the outside world to multiple subcortical targets within the brain. This information is either used to dictate reflexive behaviors or relayed to the visual cortex for further processing. Many subcortical visual nuclei also receive descending inputs from projection neurons in the visual cortex. Most areas receive inputs from layer 5 cortical neurons in the visual cortex but one exception is the dorsal lateral geniculate nucleus (dLGN), which receives layer 6 inputs and is also the only RGC target that sends direct projections to the cortex. Here we ask how visual system development and function changes in mice that develop without a cortex. We find that the development of a cortex is essential for RGC axons to terminate in the dLGN, but is not required for targeting RGC axons to other subcortical nuclei. RGC axons also fail to target to the dLGN in mice that specifically lack cortical layer 6 projections to the dLGN. Finally, we show that when mice develop without a cortex they can still perform a number of vision-dependent tasks. SIGNIFICANCE STATEMENT The dorsal lateral geniculate nucleus (dLGN) is a sensory thalamic relay area that receives feedforward inputs from retinal ganglion cells (RGCs) in the retina, and feed back inputs from layer 6 neurons in the visual cortex. In this study we examined genetically manipulated mice that develop without a cortex or without cortical layer 6 axonal projections, and find that RGC axons fail to project to the dLGN. Other RGC recipient areas, such as the superior colliculus and suprachiasmatic nucleus, are targeted normally. These results provide support for a new mechanism of target selection that may be specific to the thalamus, whereby descending cortical axons provide an activity that promotes feedforward targeting of RGC axons to the dLGN.
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Molecular codes for cell type specification in Brn3 retinal ganglion cells. Proc Natl Acad Sci U S A 2017; 114:E3974-E3983. [PMID: 28465430 DOI: 10.1073/pnas.1618551114] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Visual information is conveyed from the eye to the brain by distinct types of retinal ganglion cells (RGCs). It is largely unknown how RGCs acquire their defining morphological and physiological features and connect to upstream and downstream synaptic partners. The three Brn3/Pou4f transcription factors (TFs) participate in a combinatorial code for RGC type specification, but their exact molecular roles are still unclear. We use deep sequencing to define (i) transcriptomes of Brn3a- and/or Brn3b-positive RGCs, (ii) Brn3a- and/or Brn3b-dependent RGC transcripts, and (iii) transcriptomes of retinorecipient areas of the brain at developmental stages relevant for axon guidance, dendrite formation, and synaptogenesis. We reveal a combinatorial code of TFs, cell surface molecules, and determinants of neuronal morphology that is differentially expressed in specific RGC populations and selectively regulated by Brn3a and/or Brn3b. This comprehensive molecular code provides a basis for understanding neuronal cell type specification in RGCs.
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Sweeney NT, James KN, Nistorica A, Lorig-Roach RM, Feldheim DA. Expression of transcription factors divides retinal ganglion cells into distinct classes. J Comp Neurol 2017; 527:225-235. [PMID: 28078709 DOI: 10.1002/cne.24172] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 12/16/2016] [Accepted: 12/23/2016] [Indexed: 12/12/2022]
Abstract
Retinal ganglion cells (RGCs) are tasked with transmitting all light information from the eye to the retinal recipient areas of the brain. RGCs can be classified into many different types by morphology, gene expression, axonal projections, and functional responses to different light stimuli. Ultimately, these classification systems should be unified into an all-encompassing taxonomy. Toward that end, we show here that nearly all RGCs express either Islet-2 (Isl2), Tbr2, or a combination of Satb1 and Satb2. We present gene expression data supporting the hypothesis that Satb1 and Satb2 are expressed in ON-OFF direction-selective (DS) RGCs, complementing our previous work demonstrating that RGCs that express Isl2 and Tbr2 are non-DS and non-image-forming, respectively. Expression of these transcription factors emerges at distinct embryonic ages and only in postmitotic cells. Finally, we demonstrate that these transcription factor-defined RGC classes are born throughout RGC genesis.
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Affiliation(s)
- Neal T Sweeney
- Department of Molecular, Cellular and Developmental Biology, University of California Santa Cruz, Santa Cruz, California
| | - Kiely N James
- Department of Molecular, Cellular and Developmental Biology, University of California Santa Cruz, Santa Cruz, California
| | - Andreea Nistorica
- Department of Molecular, Cellular and Developmental Biology, University of California Santa Cruz, Santa Cruz, California
| | - Ryan M Lorig-Roach
- Department of Molecular, Cellular and Developmental Biology, University of California Santa Cruz, Santa Cruz, California
| | - David A Feldheim
- Department of Molecular, Cellular and Developmental Biology, University of California Santa Cruz, Santa Cruz, California
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Monavarfeshani A, Sabbagh U, Fox MA. Not a one-trick pony: Diverse connectivity and functions of the rodent lateral geniculate complex. Vis Neurosci 2017; 34:E012. [PMID: 28965517 PMCID: PMC5755970 DOI: 10.1017/s0952523817000098] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Often mislabeled as a simple relay of sensory information, the thalamus is a complicated structure with diverse functions. This diversity is exemplified by roles visual thalamus plays in processing and transmitting light-derived stimuli. Such light-derived signals are transmitted to the thalamus by retinal ganglion cells (RGCs), the sole projection neurons of the retina. Axons from RGCs innervate more than ten distinct nuclei within thalamus, including those of the lateral geniculate complex. Nuclei within the lateral geniculate complex of nocturnal rodents, which include the dorsal lateral geniculate nucleus (dLGN), ventral lateral geniculate nucleus (vLGN), and intergeniculate leaflet (IGL), are each densely innervated by retinal projections, yet, exhibit distinct cytoarchitecture and connectivity. These features suggest that each nucleus within this complex plays a unique role in processing and transmitting light-derived signals. Here, we review the diverse cytoarchitecture and connectivity of these nuclei in nocturnal rodents, in an effort to highlight roles for dLGN in vision and for vLGN and IGL in visuomotor, vestibular, ocular, and circadian function.
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Affiliation(s)
- Aboozar Monavarfeshani
- Developmental and Translational Neurobiology Center,Virginia Tech Carilion Research Institute,Roanoke,Virginia
| | - Ubadah Sabbagh
- Developmental and Translational Neurobiology Center,Virginia Tech Carilion Research Institute,Roanoke,Virginia
| | - Michael A Fox
- Developmental and Translational Neurobiology Center,Virginia Tech Carilion Research Institute,Roanoke,Virginia
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Novel Models of Visual Topographic Map Alignment in the Superior Colliculus. PLoS Comput Biol 2016; 12:e1005315. [PMID: 28027309 PMCID: PMC5226834 DOI: 10.1371/journal.pcbi.1005315] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Revised: 01/11/2017] [Accepted: 12/16/2016] [Indexed: 01/22/2023] Open
Abstract
The establishment of precise neuronal connectivity during development is critical for sensing the external environment and informing appropriate behavioral responses. In the visual system, many connections are organized topographically, which preserves the spatial order of the visual scene. The superior colliculus (SC) is a midbrain nucleus that integrates visual inputs from the retina and primary visual cortex (V1) to regulate goal-directed eye movements. In the SC, topographically organized inputs from the retina and V1 must be aligned to facilitate integration. Previously, we showed that retinal input instructs the alignment of V1 inputs in the SC in a manner dependent on spontaneous neuronal activity; however, the mechanism of activity-dependent instruction remains unclear. To begin to address this gap, we developed two novel computational models of visual map alignment in the SC that incorporate distinct activity-dependent components. First, a Correlational Model assumes that V1 inputs achieve alignment with established retinal inputs through simple correlative firing mechanisms. A second Integrational Model assumes that V1 inputs contribute to the firing of SC neurons during alignment. Both models accurately replicate in vivo findings in wild type, transgenic and combination mutant mouse models, suggesting either activity-dependent mechanism is plausible. In silico experiments reveal distinct behaviors in response to weakening retinal drive, providing insight into the nature of the system governing map alignment depending on the activity-dependent strategy utilized. Overall, we describe novel computational frameworks of visual map alignment that accurately model many aspects of the in vivo process and propose experiments to test them.
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Struebing FL, Lee RK, Williams RW, Geisert EE. Genetic Networks in Mouse Retinal Ganglion Cells. Front Genet 2016; 7:169. [PMID: 27733864 PMCID: PMC5039302 DOI: 10.3389/fgene.2016.00169] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 09/06/2016] [Indexed: 01/17/2023] Open
Abstract
Retinal ganglion cells (RGCs) are the output neuron of the eye, transmitting visual information from the retina through the optic nerve to the brain. The importance of RGCs for vision is demonstrated in blinding diseases where RGCs are lost, such as in glaucoma or after optic nerve injury. In the present study, we hypothesize that normal RGC function is transcriptionally regulated. To test our hypothesis, we examine large retinal expression microarray datasets from recombinant inbred mouse strains in GeneNetwork and define transcriptional networks of RGCs and their subtypes. Two major and functionally distinct transcriptional networks centering around Thy1 and Tubb3 (Class III beta-tubulin) were identified. Each network is independently regulated and modulated by unique genomic loci. Meta-analysis of publically available data confirms that RGC subtypes are differentially susceptible to death, with alpha-RGCs and intrinsically photosensitive RGCs (ipRGCs) being less sensitive to cell death than other RGC subtypes in a mouse model of glaucoma.
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Affiliation(s)
- Felix L Struebing
- Department of Ophthalmology, Emory University School of Medicine Atlanta, GA, USA
| | - Richard K Lee
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine Miami, FL, USA
| | - Robert W Williams
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center Memphis, TN, USA
| | - Eldon E Geisert
- Department of Ophthalmology, Emory University School of Medicine Atlanta, GA, USA
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Shanks JA, Ito S, Schaevitz L, Yamada J, Chen B, Litke A, Feldheim DA. Corticothalamic Axons Are Essential for Retinal Ganglion Cell Axon Targeting to the Mouse Dorsal Lateral Geniculate Nucleus. J Neurosci 2016. [PMID: 27170123 DOI: 10.6080/k07d2s2f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2023] Open
Abstract
UNLABELLED Retinal ganglion cells (RGCs) relay information about the outside world to multiple subcortical targets within the brain. This information is either used to dictate reflexive behaviors or relayed to the visual cortex for further processing. Many subcortical visual nuclei also receive descending inputs from projection neurons in the visual cortex. Most areas receive inputs from layer 5 cortical neurons in the visual cortex but one exception is the dorsal lateral geniculate nucleus (dLGN), which receives layer 6 inputs and is also the only RGC target that sends direct projections to the cortex. Here we ask how visual system development and function changes in mice that develop without a cortex. We find that the development of a cortex is essential for RGC axons to terminate in the dLGN, but is not required for targeting RGC axons to other subcortical nuclei. RGC axons also fail to target to the dLGN in mice that specifically lack cortical layer 6 projections to the dLGN. Finally, we show that when mice develop without a cortex they can still perform a number of vision-dependent tasks. SIGNIFICANCE STATEMENT The dorsal lateral geniculate nucleus (dLGN) is a sensory thalamic relay area that receives feedforward inputs from retinal ganglion cells (RGCs) in the retina, and feed back inputs from layer 6 neurons in the visual cortex. In this study we examined genetically manipulated mice that develop without a cortex or without cortical layer 6 axonal projections, and find that RGC axons fail to project to the dLGN. Other RGC recipient areas, such as the superior colliculus and suprachiasmatic nucleus, are targeted normally. These results provide support for a new mechanism of target selection that may be specific to the thalamus, whereby descending cortical axons provide an activity that promotes feedforward targeting of RGC axons to the dLGN.
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Affiliation(s)
- James A Shanks
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, California 95064
| | - Shinya Ito
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, Santa Cruz, California 95064, and
| | - Laura Schaevitz
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, California 95064, Department of Biology, Trinity College, Hartford, Connecticut 06106
| | - Jena Yamada
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, California 95064
| | - Bin Chen
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, California 95064
| | - Alan Litke
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, Santa Cruz, California 95064, and
| | - David A Feldheim
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, California 95064,
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Owens MT, Feldheim DA, Stryker MP, Triplett JW. Stochastic Interaction between Neural Activity and Molecular Cues in the Formation of Topographic Maps. Neuron 2015; 87:1261-1273. [PMID: 26402608 DOI: 10.1016/j.neuron.2015.08.030] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Revised: 07/23/2015] [Accepted: 08/18/2015] [Indexed: 11/25/2022]
Abstract
Topographic maps in visual processing areas maintain the spatial order of the visual world. Molecular cues and neuronal activity both play critical roles in map formation, but their interaction remains unclear. Here, we demonstrate that when molecular- and activity-dependent cues are rendered nearly equal in force, they drive topographic mapping stochastically. The functional and anatomical representation of azimuth in the superior colliculus of heterozygous Islet2-EphA3 knockin (Isl2(EphA3/+)) mice is variable: maps may be single, duplicated, or a combination of the two. This heterogeneity is not due to genetic differences, since map organizations in individual mutant animals often differ between colliculi. Disruption of spontaneous waves of retinal activity resulted in uniform map organization in Isl2(EphA3/+) mice, demonstrating that correlated spontaneous activity is required for map heterogeneity. Computational modeling replicates this heterogeneity, revealing that molecular- and activity-dependent forces interact simultaneously and stochastically during topographic map formation.
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Affiliation(s)
- Melinda T Owens
- Center for Integrative Neuroscience and Departments of Physiology and Bioengineering & Therapeutic Sciences, University of California, San Francisco, San Francisco, CA 94143, USA
| | - David A Feldheim
- Molecular, Cell & Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Michael P Stryker
- Center for Integrative Neuroscience and Departments of Physiology and Bioengineering & Therapeutic Sciences, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jason W Triplett
- Molecular, Cell & Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA 95064, USA; Center for Neuroscience Research, Children's National Health System, Washington, DC 20010, USA.
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Kim T, Soto F, Kerschensteiner D. An excitatory amacrine cell detects object motion and provides feature-selective input to ganglion cells in the mouse retina. eLife 2015; 4. [PMID: 25988808 PMCID: PMC4467229 DOI: 10.7554/elife.08025] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 05/18/2015] [Indexed: 11/16/2022] Open
Abstract
Retinal circuits detect salient features of the visual world and report them to the brain through spike trains of retinal ganglion cells. The most abundant ganglion cell type in mice, the so-called W3 ganglion cell, selectively responds to movements of small objects. Where and how object motion sensitivity arises in the retina is incompletely understood. In this study, we use 2-photon-guided patch-clamp recordings to characterize responses of vesicular glutamate transporter 3 (VGluT3)-expressing amacrine cells (ACs) to a broad set of visual stimuli. We find that these ACs are object motion sensitive and analyze the synaptic mechanisms underlying this computation. Anatomical circuit reconstructions suggest that VGluT3-expressing ACs form glutamatergic synapses with W3 ganglion cells, and targeted recordings show that the tuning of W3 ganglion cells' excitatory input matches that of VGluT3-expressing ACs' responses. Synaptic excitation of W3 ganglion cells is diminished, and responses to object motion are suppressed in mice lacking VGluT3. Object motion, thus, is first detected by VGluT3-expressing ACs, which provide feature-selective excitatory input to W3 ganglion cells. DOI:http://dx.doi.org/10.7554/eLife.08025.001 Animals can use their eyes to detect moving objects, which helps them to avoid predators and other threats, and to spot potential prey or allies. Visual information from the eyes is sent to the brain, which processes the information to form a coherent picture of how the objects are moving. This processing has to be able to account for movements of the head, eyes, and body—which can cause the image of an object on the retina within the eye to move even if the object itself remains stationary. Within the retina, light is converted into electrical signals by cells called rods and cones. A layer of cells called bipolar cells relay these signals to the ‘ganglion’ cells, which in turn pass them on to the brain. In mice, a type of ganglion cell called the W3 ganglion cell has been shown to respond selectively to small moving objects, but exactly how these cells acquire their motion sensitivity remained unclear. Kim et al. now reveal that cells called amacrine cells, which regulate the transfer of signals from the bipolar cells to ganglion cells, supply the information needed for motion detection. The mouse eye contains up to 50 different types of amacrine cells. One of these—called the VG3-amacrine cell—increases its activity whenever an object moves relative to its background, but decreases its activity whenever the object and background move together. The overall effect is that the cells respond selectively to the presence of small moving objects. Most amacrine cells regulate the transfer of signals within the retina by inhibiting the activity of ganglion cells. But, Kim et al. show that VG3-amacrine cells release a molecule called glutamate to activate W3 ganglion cells when a moving object is detected. These unusual and specialized cells are, thus, an essential component of a circuit in the nervous system that supports motion detection. It is possible that some other types of amacrine cells may also play specialized roles in the detection of other features in the visual world. DOI:http://dx.doi.org/10.7554/eLife.08025.002
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Affiliation(s)
- Tahnbee Kim
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States
| | - Florentina Soto
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States
| | - Daniel Kerschensteiner
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, Saint Louis, United States
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Sun LO, Brady CM, Cahill H, Al-Khindi T, Sakuta H, Dhande OS, Noda M, Huberman AD, Nathans J, Kolodkin AL. Functional assembly of accessory optic system circuitry critical for compensatory eye movements. Neuron 2015; 86:971-984. [PMID: 25959730 DOI: 10.1016/j.neuron.2015.03.064] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Revised: 02/09/2015] [Accepted: 03/24/2015] [Indexed: 10/23/2022]
Abstract
Accurate motion detection requires neural circuitry that compensates for global visual field motion. Select subtypes of retinal ganglion cells perceive image motion and connect to the accessory optic system (AOS) in the brain, which generates compensatory eye movements that stabilize images during slow visual field motion. Here, we show that the murine transmembrane semaphorin 6A (Sema6A) is expressed in a subset of On direction-selective ganglion cells (On DSGCs) and is required for retinorecipient axonal targeting to the medial terminal nucleus (MTN) of the AOS. Plexin A2 and A4, two Sema6A binding partners, are expressed in MTN cells, attract Sema6A(+) On DSGC axons, and mediate MTN targeting of Sema6A(+) RGC projections. Furthermore, Sema6A/Plexin-A2/A4 signaling is required for the functional output of the AOS. These data reveal molecular mechanisms underlying the assembly of AOS circuits critical for moving image perception.
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Affiliation(s)
- Lu O Sun
- The Solomon H. Snyder Department of Neuroscience, Howard Hughes Medical Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Colleen M Brady
- The Solomon H. Snyder Department of Neuroscience, Howard Hughes Medical Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hugh Cahill
- Department of Molecular Biology and Genetics, Department of Neuroscience, Department of Ophthalmology, Howard Hughes Medical Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Timour Al-Khindi
- The Solomon H. Snyder Department of Neuroscience, Howard Hughes Medical Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Hiraki Sakuta
- Division of Molecular Neuroscience, National Institute for Basic Biology, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787, Japan
| | - Onkar S Dhande
- Department of Neurosciences, Neurobiology Section in the Division of Biological Sciences, Department of Ophthalmology, University of California, San Diego, San Diego, CA 92093, USA
| | - Masaharu Noda
- Division of Molecular Neuroscience, National Institute for Basic Biology, 5-1 Higashiyama, Myodaiji-cho, Okazaki 444-8787, Japan
| | - Andrew D Huberman
- Department of Neurosciences, Neurobiology Section in the Division of Biological Sciences, Department of Ophthalmology, University of California, San Diego, San Diego, CA 92093, USA
| | - Jeremy Nathans
- Department of Molecular Biology and Genetics, Department of Neuroscience, Department of Ophthalmology, Howard Hughes Medical Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Alex L Kolodkin
- The Solomon H. Snyder Department of Neuroscience, Howard Hughes Medical Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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Soares CA, Mason CA. Transient ipsilateral retinal ganglion cell projections to the brain: Extent, targeting, and disappearance. Dev Neurobiol 2015; 75:1385-401. [PMID: 25788284 DOI: 10.1002/dneu.22291] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 03/13/2015] [Accepted: 03/15/2015] [Indexed: 12/27/2022]
Abstract
During development of the mammalian eye, the first retinal ganglion cells (RGCs) that extend to the brain are located in the dorsocentral (DC) retina. These RGCs extend to either ipsilateral or contralateral targets, but the ipsilateral projections do not survive into postnatal periods. The function and means of disappearance of the transient ipsilateral projection are not known. We have followed the course of this transient early ipsilateral cohort of RGCs, paying attention to how far they extend, whether they enter targets and if so, which ones, and the time course of their disappearance. The DC ipsilateral RGC axons were traced using DiI labeling at E13.5 and E15.5 to compare the proportion of ipsi- versus contralateral projections during the first period of growth. In utero electroporation of E12.5 retina with GFP constructs was used to label axons that could be visualized at succeeding time points into postnatal ages. Our results show that the earliest ipsilateral axons grow along the cellular border of the brain, and are segregated from the laterally positioned contralateral axons from the same retinal origin. In agreement with previous reports, although many early RGCs extend ipsilaterally, after E16 their number rapidly declines. Nonetheless, some ipsilateral axons from the DC retina enter the superior colliculus and arborize minimally, but very few enter the dorsal lateral geniculate nucleus and those that do extend only short branches. While the mechanism of selective axonal disappearance remains elusive, these data give further insight into establishment of the visual pathways.
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Affiliation(s)
- Célia A Soares
- Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York.,Life and Health Science Research Institute, School of Health Sciences, University of Minho, Braga, Portugal.,ICVS/3B's, PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Carol A Mason
- Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York.,Department of Neuroscience, College of Physicians and Surgeons, Columbia University, New York.,Department of Ophthalmology, College of Physicians and Surgeons, Columbia University, New York
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Onecut1 and Onecut2 redundantly regulate early retinal cell fates during development. Proc Natl Acad Sci U S A 2014; 111:E4086-95. [PMID: 25228773 DOI: 10.1073/pnas.1405354111] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Previously, we have shown that Onecut1 (Oc1) and Onecut2 (Oc2) are expressed in retinal progenitor cells, developing retinal ganglion cells (RGCs), and horizontal cells (HCs). However, in Oc1-null mice, we only observed an 80% reduction in HCs, but no defects in other cell types. We postulated that the lack of defects in other cell types in Oc1-null retinas was a result of redundancy with Oc2. To test this theory, we have generated Oc2-null mice and now show that their retinas also only have defects in HCs, with a 50% reduction in their numbers. However, when both Oc1 and Oc2 are knocked out, the retinas exhibit more profound defects in the development of all early retinal cell types, including completely failed genesis of HCs, compromised generation of cones, reduced production (by 30%) of RGCs, and absence of starburst amacrine cells. Cone subtype diversification and RGC subtype composition also were affected in the double-null retina. Using RNA-Seq expression profiling, we have identified downstream genes of Oc1 and Oc2, which not only confirms the redundancy between the two factors and renders a molecular explanation for the defects in the double-null retinas, but also shows that the onecut factors suppress the production of the late cell type, rods, indicating that the two factors contribute to the competence of retinal progenitor cells for the early retinal cell fates. Our results provide insight into how onecut factors regulate the creation of cellular diversity in the retina and, by extension, in the central nervous system in general.
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Hammer S, Carrillo GL, Govindaiah G, Monavarfeshani A, Bircher JS, Su J, Guido W, Fox MA. Nuclei-specific differences in nerve terminal distribution, morphology, and development in mouse visual thalamus. Neural Dev 2014; 9:16. [PMID: 25011644 PMCID: PMC4108237 DOI: 10.1186/1749-8104-9-16] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 06/25/2014] [Indexed: 12/04/2022] Open
Abstract
Background Mouse visual thalamus has emerged as a powerful model for understanding the mechanisms underlying neural circuit formation and function. Three distinct nuclei within mouse thalamus receive retinal input, the dorsal lateral geniculate nucleus (dLGN), the ventral lateral geniculate nucleus (vLGN), and the intergeniculate nucleus (IGL). However, in each of these nuclei, retinal inputs are vastly outnumbered by nonretinal inputs that arise from cortical and subcortical sources. Although retinal and nonretinal terminals associated within dLGN circuitry have been well characterized, we know little about nerve terminal organization, distribution and development in other nuclei of mouse visual thalamus. Results Immunolabeling specific subsets of synapses with antibodies against vesicle-associated neurotransmitter transporters or neurotransmitter synthesizing enzymes revealed significant differences in the composition, distribution and morphology of nonretinal terminals in dLGN, vLGN and IGL. For example, inhibitory terminals are more densely packed in vLGN, and cortical terminals are more densely distributed in dLGN. Overall, synaptic terminal density appears least dense in IGL. Similar nuclei-specific differences were observed for retinal terminals using immunolabeling, genetic labeling, axonal tracing and serial block face scanning electron microscopy: retinal terminals are smaller, less morphologically complex, and more densely distributed in vLGN than in dLGN. Since glutamatergic terminal size often correlates with synaptic function, we used in vitro whole cell recordings and optic tract stimulation in acutely prepared thalamic slices to reveal that excitatory postsynaptic currents (EPSCs) are considerably smaller in vLGN and show distinct responses following paired stimuli. Finally, anterograde labeling of retinal terminals throughout early postnatal development revealed that anatomical differences in retinal nerve terminal structure are not observable as synapses initially formed, but rather developed as retinogeniculate circuits mature. Conclusions Taken together, these results reveal nuclei-specific differences in nerve terminal composition, distribution, and morphology in mouse visual thalamus. These results raise intriguing questions about the different functions of these nuclei in processing light-derived information, as well as differences in the mechanisms that underlie their unique, nuclei-specific development.
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Affiliation(s)
| | | | | | | | | | | | | | - Michael A Fox
- Virginia Tech Carilion Research Institute, 2 Riverside Circle, Roanoke, VA 24016, USA.
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Wagner E, Stolfi A, Gi Choi Y, Levine M. Islet is a key determinant of ascidian palp morphogenesis. Development 2014; 141:3084-92. [PMID: 24993943 DOI: 10.1242/dev.110684] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The anterior-most ectoderm of ascidian larvae contains the adhesive papillae, or palps, which play an important role in triggering the metamorphosis of swimming tadpoles. In Ciona intestinalis, the palps consist of three conical protrusions within a field of thickened epithelium that form late in embryogenesis, as tailbuds mature into larvae. The palp protrusions express the LIM-homeodomain transcription factor Islet. Protrusion occurs through differential cell elongation, probably mediated by Islet, as we find that ectopic expression of Islet is sufficient to promote cell lengthening. FGF signaling is required for both Islet expression and palp morphogenesis. Importantly, we show that Islet expression can rescue the palp-deficient phenotype that results from inhibition of FGF signaling. We conclude that Islet is a key regulatory factor governing morphogenesis of the palps. It is conceivable that Islet is also essential for the cellular morphogenesis of placode-derived sensory neurons in vertebrates.
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Affiliation(s)
- Eileen Wagner
- Center for Integrative Genomics, Division of Genetics, Genomics, and Development, Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley, CA 94720, USA
| | - Alberto Stolfi
- New York University, Center for Developmental Genetics, Department of Biology, 1009 Silver Center, 100 Washington Square East, New York, NY 10003-6688, USA
| | - Yoon Gi Choi
- Functional Genomics Laboratory, Department of Molecular and Cell Biology, University of California-Berkeley, 255 Life Sciences Addition #3200, Berkeley, CA 94720-3200, USA
| | - Mike Levine
- Center for Integrative Genomics, Division of Genetics, Genomics, and Development, Department of Molecular and Cell Biology, University of California-Berkeley, Berkeley, CA 94720, USA
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Abstract
There are ∼20 types of retinal ganglion cells (RGCs) in mice, each of which has distinct molecular, morphological, and physiological characteristics. Each RGC type sends axon projections to specific brain areas that execute light-dependent behaviors. Here, we show that the T-box transcription factor Tbr2 is required for the development of several RGC types that participate in non-image-forming circuits. These types are molecularly distinct, project to non-image-forming targets, and include intrinsically photosensitive RGCs. Tbr2 mutant mice have reduced retinal projections to non-image-forming nuclei and an attenuated pupillary light reflex. These data demonstrate that Tbr2 acts to execute RGC type choice and/or survival in a set of RGCs that mediates light-induced subconscious behaviors.
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Mathis C, Savier E, Bott JB, Clesse D, Bevins N, Sage-Ciocca D, Geiger K, Gillet A, Laux-Biehlmann A, Goumon Y, Lacaud A, Lelièvre V, Kelche C, Cassel JC, Pfrieger FW, Reber M. Defective response inhibition and collicular noradrenaline enrichment in mice with duplicated retinotopic map in the superior colliculus. Brain Struct Funct 2014; 220:1573-84. [PMID: 24647754 PMCID: PMC4409641 DOI: 10.1007/s00429-014-0745-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 02/28/2014] [Indexed: 10/27/2022]
Abstract
The superior colliculus is a hub for multisensory integration necessary for visuo-spatial orientation, control of gaze movements and attention. The multiple functions of the superior colliculus have prompted hypotheses about its involvement in neuropsychiatric conditions, but to date, this topic has not been addressed experimentally. We describe experiments on genetically modified mice, the Isl2-EphA3 knock-in line, that show a well-characterized duplication of the retino-collicular and cortico-collicular axonal projections leading to hyperstimulation of the superior colliculus. To explore the functional impact of collicular hyperstimulation, we compared the performance of homozygous knock-in, heterozygous knock-in and wild-type mice in several behavioral tasks requiring collicular activity. The light/dark box test and Go/No-Go conditioning task revealed that homozygous mutant mice exhibit defective response inhibition, a form of impulsivity. This defect was specific to attention as other tests showed no differences in visually driven behavior, motivation, visuo-spatial learning and sensorimotor abilities among the different groups of mice. Monoamine quantification and gene expression profiling demonstrated a specific enrichment of noradrenaline only in the superficial layers of the superior colliculus of Isl2-EphA3 knock-in mice, where the retinotopy is duplicated, whereas transcript levels of receptors, transporters and metabolic enzymes of the monoaminergic pathway were not affected. We demonstrate that the defect in response inhibition is a consequence of noradrenaline imbalance in the superficial layers of the superior colliculus caused by retinotopic map duplication. Our results suggest that structural abnormalities in the superior colliculus can cause defective response inhibition, a key feature of attention-deficit disorders.
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Affiliation(s)
- Chantal Mathis
- Laboratory of Adaptative and Cognitive Neurosciences, CNRS, University of Strasbourg UMR 7364, 67000 Strasbourg, France
| | - Elise Savier
- Institute of Cellular and Integrative Neurosciences, CNRS UPR 3212, University of Strasbourg, 5, rue blaise Pascal, 67084 Strasbourg, France
| | - Jean-Bastien Bott
- Laboratory of Adaptative and Cognitive Neurosciences, CNRS, University of Strasbourg UMR 7364, 67000 Strasbourg, France
| | - Daniel Clesse
- Institute of Cellular and Integrative Neurosciences, CNRS UPR 3212, University of Strasbourg, 5, rue blaise Pascal, 67084 Strasbourg, France
| | - Nicholas Bevins
- Molecular Neurobiology Laboratory, The Salk Institute, La Jolla, San Diego, CA 92037 USA
- Department of Neurosciences, University of California, La Jolla, San Diego, CA 92039 USA
| | | | - Karin Geiger
- Laboratory of Adaptative and Cognitive Neurosciences, CNRS, University of Strasbourg UMR 7364, 67000 Strasbourg, France
| | - Anaïs Gillet
- Laboratory of Adaptative and Cognitive Neurosciences, CNRS, University of Strasbourg UMR 7364, 67000 Strasbourg, France
| | - Alexis Laux-Biehlmann
- Institute of Cellular and Integrative Neurosciences, CNRS UPR 3212, University of Strasbourg, 5, rue blaise Pascal, 67084 Strasbourg, France
| | - Yannick Goumon
- Institute of Cellular and Integrative Neurosciences, CNRS UPR 3212, University of Strasbourg, 5, rue blaise Pascal, 67084 Strasbourg, France
| | - Adrien Lacaud
- Institute of Cellular and Integrative Neurosciences, CNRS UPR 3212, University of Strasbourg, 5, rue blaise Pascal, 67084 Strasbourg, France
| | - Vincent Lelièvre
- Institute of Cellular and Integrative Neurosciences, CNRS UPR 3212, University of Strasbourg, 5, rue blaise Pascal, 67084 Strasbourg, France
| | - Christian Kelche
- Laboratory of Adaptative and Cognitive Neurosciences, CNRS, University of Strasbourg UMR 7364, 67000 Strasbourg, France
| | - Jean-Christophe Cassel
- Laboratory of Adaptative and Cognitive Neurosciences, CNRS, University of Strasbourg UMR 7364, 67000 Strasbourg, France
| | - Frank W. Pfrieger
- Institute of Cellular and Integrative Neurosciences, CNRS UPR 3212, University of Strasbourg, 5, rue blaise Pascal, 67084 Strasbourg, France
| | - Michael Reber
- Institute of Cellular and Integrative Neurosciences, CNRS UPR 3212, University of Strasbourg, 5, rue blaise Pascal, 67084 Strasbourg, France
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