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Yu M, Hao W, Wang M, Ruan Z, Li Z, Xiang C, Wang L, Hu Y, Yang X. Characterizing Retinal Sensitivity and Structure in Congenital Stationary Night Blindness: A Combined Microperimetry and OCT Study. Invest Ophthalmol Vis Sci 2024; 65:35. [PMID: 38916884 PMCID: PMC11204054 DOI: 10.1167/iovs.65.6.35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Accepted: 05/17/2024] [Indexed: 06/26/2024] Open
Abstract
Purpose To investigate the characteristics of microperimetry and optical coherence tomography (OCT) in congenital stationary night blindness (CSNB), as well as their structure-function association. Methods This cross-sectional study included 32 eyes from 32 participants with CSNB, comprising 18 with complete CSNB and 14 with incomplete CSNB, along with 36 eyes from 36 CSNB-unaffected controls matched for age, sex, and spherical equivalent. Using MP-3 microperimetry, central retinal sensitivity was assessed within a 20° field, distributed across six concentric rings (0°, 2°, 4°, 6°, 8°, and 10°). OCT was used to analyze retinal and choroidal thickness. The study aimed to assess the overall and ring-wise retinal sensitivity, as well as choroidal and retinal thickness in CSNB and CSNB-unaffected controls, with a secondary focus on the relationship between retinal sensitivity and microstructural features on OCT. Results In comparison with CSNB-unaffected subjects, the overall and ring-wise retinal sensitivity as well as choroidal thickness were reduced in patients with CSNB (P < 0.001). Moreover, the central sensitivity in incomplete CSNB group was lower than in complete CSNB group (25.72 ± 3.93 dB vs. 21.92 ± 4.10 dB; P < 0.001). The retinal thickness in the CSNB group was thinner outside the fovea compared with the CSNB-unaffected group. Multiple mixed regression analyses revealed that point-to-point retinal sensitivity was significantly correlated with BCVA (P = 0.002) and the corresponding retinal thickness (P = 0.004). Conclusions Examination of retinal sensitivity and OCT revealed different spatial distribution profiles in CSNB and its subtypes. In CSNB eyes, retinal sensitivity on microperimetry was associated with retinal thickness on OCT.
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Affiliation(s)
- Mengting Yu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Wenlong Hao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Mengyi Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Zhenbang Ruan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Zixuan Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Chuqi Xiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Lili Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Yin Hu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
| | - Xiao Yang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangzhou, China
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Hou YJ, Yang XX, He L, Meng HX. Pathological mechanisms of cold and mechanical stress in modulating cancer progression. Hum Cell 2024; 37:593-606. [PMID: 38538930 DOI: 10.1007/s13577-024-01049-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/22/2024] [Indexed: 04/15/2024]
Abstract
Environmental temperature and cellular mechanical force are the inherent factors that participate in various biological processes and regulate cancer progress, which have been hot topics worldwide. They occupy a dominant part in the cancer tissues through different approaches. However, extensive investigation regarding pathological mechanisms in the carcinogenic field. After research, we found cold stress via two means to manipulate tumors: neuroscience and mechanically sensitive ion channels (MICHs) such as TRP families to regulate the physiological and pathological activities. Excessive cold stimulation mediated neuroscience acting on every cancer stage through the hypothalamus-pituitary-adrenocorticoid (HPA) to reach the target organs. Comparatively speaking, mechanical force via Piezo of MICHs controls cancer development. The progression of cancer depends on the internal activation of proto-oncogenes and the external tumorigenic factors; the above two means eventually lead to genetic disorders at the molecular level. This review summarizes the interaction of bidirectional communication between them and the tumor. It covers the main processes from cytoplasm to nucleus related to metastasis cascade and tumor immune escape.
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Affiliation(s)
- Yun-Jing Hou
- Harbin Medical University, Harbin, China
- Department of Precision Medicine Center, Harbin Medical University Cancer Hospital, Harbin, China
| | - Xin-Xin Yang
- Harbin Medical University, Harbin, China
- Department of Precision Medicine Center, Harbin Medical University Cancer Hospital, Harbin, China
| | - Lin He
- Department of Stomatology, Heilongjiang Provincial Hospital, Harbin, China
| | - Hong-Xue Meng
- Harbin Medical University, Harbin, China.
- Department of Pathology, Harbin Medical University Cancer Hospital, 150 Haping Road, Harbin, China.
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Kawashima R, Matsushita K, Mandai K, Sugita Y, Maruo T, Mizutani K, Midoh Y, Oguchi A, Murakawa Y, Kuniyoshi K, Sato R, Furukawa T, Nishida K, Takai Y. Necl-1/CADM3 regulates cone synapse formation in the mouse retina. iScience 2024; 27:109577. [PMID: 38623325 PMCID: PMC11016759 DOI: 10.1016/j.isci.2024.109577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 12/22/2023] [Accepted: 03/25/2024] [Indexed: 04/17/2024] Open
Abstract
In vertebrates, retinal neural circuitry for visual perception is organized in specific layers. The outer plexiform layer is the first synaptic region in the visual pathway, where photoreceptor synaptic terminals connect with bipolar and horizontal cell processes. However, molecular mechanisms underlying cone synapse formation to mediate OFF pathways remain unknown. This study reveals that Necl-1/CADM3 is localized at S- and S/M-opsin-containing cones and dendrites of type 4 OFF cone bipolar cells (CBCs). In Necl-1-/- mouse retina, synapses between cones and type 4 OFF CBCs were dislocated, horizontal cell distribution became abnormal, and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors were dislocated. Necl-1-/- mice exhibited aberrant short-wavelength-light-elicited signal transmission from cones to OFF CBCs, which was rescued by AMPA receptor potentiator. Additionally, Necl-1-/- mice showed impaired optokinetic responses. These findings suggest that Necl-1 regulates cone synapse formation to mediate OFF cone pathways elicited by short-wavelength light in mouse retina.
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Affiliation(s)
- Rumi Kawashima
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871, Japan
| | - Kenji Matsushita
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871, Japan
| | - Kenji Mandai
- Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo 650-0047, Japan
- Department of Molecular and Cellular Neurobiology, Kitasato University Graduate School of Medical Sciences, Sagamihara, Kanagawa 252-0374, Japan
- Department of Biochemistry, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Yuko Sugita
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan
| | - Tomohiko Maruo
- Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo 650-0047, Japan
- Department of Molecular and Cellular Neurobiology, Kitasato University Graduate School of Medical Sciences, Sagamihara, Kanagawa 252-0374, Japan
| | - Kiyohito Mizutani
- Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo 650-0047, Japan
- Division of Pathogenetic Signaling, Institute of Advanced Medical Sciences, Tokushima University, Tokushima 770-8503, Japan
| | - Yoshihiro Midoh
- Graduate School of Information Science and Technology, Osaka University, Suita, Osaka 565-0871, Japan
| | - Akiko Oguchi
- RIKEN-IFOM Joint Laboratory for Cancer Genomics, IMS RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa 230-0045, Japan
| | - Yasuhiro Murakawa
- RIKEN-IFOM Joint Laboratory for Cancer Genomics, IMS RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa 230-0045, Japan
| | - Kazuki Kuniyoshi
- Department of Ophthalmology, Kindai University Faculty of Medicine, Osakasayama, Osaka 589-8511, Japan
| | - Ryohei Sato
- Forefront Research Center for Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Takahisa Furukawa
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan
| | - Kohji Nishida
- Department of Ophthalmology, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871, Japan
| | - Yoshimi Takai
- Division of Pathogenetic Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe, Hyogo 650-0047, Japan
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Hölzel MB, Kamermans W, Winkelman BHJ, Howlett MHC, De Zeeuw CI, Kamermans M. A common cause for nystagmus in different congenital stationary night blindness mouse models. J Physiol 2023; 601:5317-5340. [PMID: 37864560 DOI: 10.1113/jp284965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 09/22/2023] [Indexed: 10/23/2023] Open
Abstract
In Nyxnob mice, a model for congenital nystagmus associated with congenital stationary night blindness (CSNB), synchronous oscillating retinal ganglion cells (RGCs) lead to oscillatory eye movements, i.e. nystagmus. Given the specific expression of mGluR6 and Cav 1.4 in the photoreceptor to bipolar cell synapses, as well as their clinical association with CSNB, we hypothesize that Grm6nob3 and Cav 1.4-KO mutants show, like the Nyxnob mouse, oscillations in both their RGC activity and eye movements. Using multi-electrode array recordings of RGCs and measurements of the eye movements, we demonstrate that Grm6nob3 and Cav 1.4-KO mice also show oscillations of their RGCs as well as a nystagmus. Interestingly, the preferred frequencies of RGC activity as well as the eye movement oscillations of the Grm6nob3 , Cav 1.4-KO and Nyxnob mice differ among mutants, but the neuronal activity and eye movement behaviour within a strain remain aligned in the same frequency domain. Model simulations indicate that mutations affecting the photoreceptor-bipolar cell synapse can form a common cause of the nystagmus of CSNB by driving oscillations in RGCs via AII amacrine cells. KEY POINTS: In Nyxnob mice, a model for congenital nystagmus associated with congenital stationary night blindness (CSNB), their oscillatory eye movements (i.e. nystagmus) are caused by synchronous oscillating retinal ganglion cells. Here we show that the same mechanism applies for two other CSNB mouse models - Grm6nob3 and Cav 1.4-KO mice. We propose that the retinal ganglion cell oscillations originate in the AII amacrine cells. Model simulations show that by only changing the input to ON-bipolar cells, all phenotypical differences between the various genetic mouse models can be reproduced.
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Affiliation(s)
- Maj-Britt Hölzel
- Netherlands Institute for Neuroscience Amsterdam, Amsterdam, the Netherlands
| | - Wouter Kamermans
- Netherlands Institute for Neuroscience Amsterdam, Amsterdam, the Netherlands
| | - Beerend H J Winkelman
- Netherlands Institute for Neuroscience Amsterdam, Amsterdam, the Netherlands
- Department of Neuroscience, Erasmus MC, Rotterdam, the Netherlands
| | - Marcus H C Howlett
- Netherlands Institute for Neuroscience Amsterdam, Amsterdam, the Netherlands
| | - Chris I De Zeeuw
- Netherlands Institute for Neuroscience Amsterdam, Amsterdam, the Netherlands
- Department of Neuroscience, Erasmus MC, Rotterdam, the Netherlands
| | - Maarten Kamermans
- Netherlands Institute for Neuroscience Amsterdam, Amsterdam, the Netherlands
- Department of Biomedical Physics, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
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5
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Wakeham CM, Shi Q, Ren G, Haley TL, Duvoisin RM, von Gersdorff H, Morgans CW. Trophoblast glycoprotein is required for efficient synaptic vesicle exocytosis from retinal rod bipolar cells. Front Cell Neurosci 2023; 17:1306006. [PMID: 38099150 PMCID: PMC10720453 DOI: 10.3389/fncel.2023.1306006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 11/02/2023] [Indexed: 12/17/2023] Open
Abstract
Introduction Rod bipolar cells (RBCs) faithfully transmit light-driven signals from rod photoreceptors in the outer retina to third order neurons in the inner retina. Recently, significant work has focused on the role of leucine-rich repeat (LRR) proteins in synaptic development and signal transduction at RBC synapses. We previously identified trophoblast glycoprotein (TPBG) as a novel transmembrane LRR protein localized to the dendrites and axon terminals of RBCs. Methods We examined the effects on RBC physiology and retinal processing of TPBG genetic knockout in mice using immunofluorescence and electron microscopy, electroretinogram recording, patch-clamp electrophysiology, and time-resolved membrane capacitance measurements. Results The scotopic electroretinogram showed a modest increase in the b-wave and a marked attenuation in oscillatory potentials in the TPBG knockout. No effect of TPBG knockout was observed on the RBC dendritic morphology, TRPM1 currents, or RBC excitability. Because scotopic oscillatory potentials primarily reflect RBC-driven rhythmic activity of the inner retina, we investigated the contribution of TPBG to downstream transmission from RBCs to third-order neurons. Using electron microscopy, we found shorter synaptic ribbons in TPBG knockout axon terminals in RBCs. Time-resolved capacitance measurements indicated that TPBG knockout reduces synaptic vesicle exocytosis and subsequent GABAergic reciprocal feedback without altering voltage-gated Ca2+ currents. Discussion TPBG is required for normal synaptic ribbon development and efficient neurotransmitter release from RBCs to downstream cells. Our results highlight a novel synaptic role for TPBG at RBC ribbon synapses and support further examination into the mechanisms by which TPBG regulates RBC physiology and circuit function.
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Affiliation(s)
- Colin M. Wakeham
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Qing Shi
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Gaoying Ren
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Tammie L. Haley
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Robert M. Duvoisin
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
| | - Henrique von Gersdorff
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
- Vollum Institute, Oregon Health and Science University, Portland, OR, United States
- Casey Eye Institute, Oregon Health and Science University, Portland, OR, United States
| | - Catherine W. Morgans
- Department of Chemical Physiology and Biochemistry, Oregon Health and Science University, Portland, OR, United States
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6
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Shimohata A, Rai D, Akagi T, Usui S, Ogiwara I, Kaneda M. The intracellular C-terminal domain of mGluR6 contains ER retention motifs. Mol Cell Neurosci 2023; 126:103875. [PMID: 37352898 DOI: 10.1016/j.mcn.2023.103875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 06/15/2023] [Accepted: 06/19/2023] [Indexed: 06/25/2023] Open
Abstract
Metabotropic glutamate receptor 6 (mGluR6) predominantly localizes to the postsynaptic sites of retinal ON-bipolar cells, at which it recognizes glutamate released from photoreceptors. The C-terminal domain (CTD) of mGluR6 contains a cluster of basic amino acids resembling motifs for endoplasmic reticulum (ER) retention. We herein investigated whether these basic residues are involved in regulating the subcellular localization of mGluR6 in 293T cells expressing mGluR6 CTD mutants using immunocytochemistry, immunoprecipitation, and flow cytometry. We showed that full-length mGluR6 localized to the ER and cell surface, whereas mGluR6 mutants with 15- and 20-amino acid deletions from the C terminus localized to the ER, but were deficient at the cell surface. We also demonstrated that the cell surface deficiency of mGluR6 mutants was rescued by introducing an alanine substitution at basic residues within the CTD. The surface-deficient mGluR6 mutant still did not localize to the cell surface and was retained in the ER when co-expressed with surface-expressible constructs, including full-length mGluR6, even though surface-deficient and surface-expressible constructs formed heteromeric complexes. The co-expression of the surface-deficient mGluR6 mutant reduced the surface levels of surface-expressible constructs. These results indicate that basic residues in the mGluR6 CTD served as ER retention signals. We suggest that exposed ER retention motifs in the aberrant assembly containing truncated or misfolded mGluR6 prevent these protein complexes from being transported to the cell surface.
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Affiliation(s)
- Atsushi Shimohata
- Department of Physiology, Nippon Medical School, Tokyo 113-8602, Japan
| | - Dilip Rai
- Department of Physiology, Nippon Medical School, Tokyo 113-8602, Japan
| | - Takumi Akagi
- Department of Physiology, Nippon Medical School, Tokyo 113-8602, Japan
| | - Sumiko Usui
- Department of Physiology, Nippon Medical School, Tokyo 113-8602, Japan
| | - Ikuo Ogiwara
- Department of Physiology, Nippon Medical School, Tokyo 113-8602, Japan.
| | - Makoto Kaneda
- Department of Physiology, Nippon Medical School, Tokyo 113-8602, Japan
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7
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Zeitz C, Roger JE, Audo I, Michiels C, Sánchez-Farías N, Varin J, Frederiksen H, Wilmet B, Callebert J, Gimenez ML, Bouzidi N, Blond F, Guilllonneau X, Fouquet S, Léveillard T, Smirnov V, Vincent A, Héon E, Sahel JA, Kloeckener-Gruissem B, Sennlaub F, Morgans CW, Duvoisin RM, Tkatchenko AV, Picaud S. Shedding light on myopia by studying complete congenital stationary night blindness. Prog Retin Eye Res 2023; 93:101155. [PMID: 36669906 DOI: 10.1016/j.preteyeres.2022.101155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 01/20/2023]
Abstract
Myopia is the most common eye disorder, caused by heterogeneous genetic and environmental factors. Rare progressive and stationary inherited retinal disorders are often associated with high myopia. Genes implicated in myopia encode proteins involved in a variety of biological processes including eye morphogenesis, extracellular matrix organization, visual perception, circadian rhythms, and retinal signaling. Differentially expressed genes (DEGs) identified in animal models mimicking myopia are helpful in suggesting candidate genes implicated in human myopia. Complete congenital stationary night blindness (cCSNB) in humans and animal models represents an ON-bipolar cell signal transmission defect and is also associated with high myopia. Thus, it represents also an interesting model to identify myopia-related genes, as well as disease mechanisms. While the origin of night blindness is molecularly well established, further research is needed to elucidate the mechanisms of myopia development in subjects with cCSNB. Using whole transcriptome analysis on three different mouse models of cCSNB (in Gpr179-/-, Lrit3-/- and Grm6-/-), we identified novel actors of the retinal signaling cascade, which are also novel candidate genes for myopia. Meta-analysis of our transcriptomic data with published transcriptomic databases and genome-wide association studies from myopia cases led us to propose new biological/cellular processes/mechanisms potentially at the origin of myopia in cCSNB subjects. The results provide a foundation to guide the development of pharmacological myopia therapies.
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Affiliation(s)
- Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.
| | - Jérome E Roger
- Paris-Saclay Institute of Neuroscience, CERTO-Retina France, CNRS, Université Paris-Saclay, Saclay, France
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France; CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, Paris, France
| | | | | | - Juliette Varin
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Helen Frederiksen
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Baptiste Wilmet
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Jacques Callebert
- Service of Biochemistry and Molecular Biology, INSERM U942, Hospital Lariboisière, APHP, Paris, France
| | | | - Nassima Bouzidi
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Frederic Blond
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Stéphane Fouquet
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Vasily Smirnov
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Ajoy Vincent
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON, Canada; Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada; Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Elise Héon
- Department of Ophthalmology and Vision Sciences, The Hospital for Sick Children, Toronto, ON, Canada; Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, ON, Canada; Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France; CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, Paris, France; Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | | | - Florian Sennlaub
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Catherine W Morgans
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, USA
| | - Robert M Duvoisin
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR, USA
| | - Andrei V Tkatchenko
- Oujiang Laboratory, Zhejiang Laboratory for Regenerative Medicine, Vision and Brain Health, Wenzhou, China; Department of Ophthalmology, Edward S. Harkness Eye Institute, Columbia University, New York, NY, USA
| | - Serge Picaud
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
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8
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Ciaglia T, Vestuto V, Bertamino A, González-Muñiz R, Gómez-Monterrey I. On the modulation of TRPM channels: Current perspectives and anticancer therapeutic implications. Front Oncol 2023; 12:1065935. [PMID: 36844925 PMCID: PMC9948629 DOI: 10.3389/fonc.2022.1065935] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 12/15/2022] [Indexed: 02/11/2023] Open
Abstract
The transient melastatin receptor potential (TRPM) ion channel subfamily functions as cellular sensors and transducers of critical biological signal pathways by regulating ion homeostasis. Some members of TRPM have been cloned from cancerous tissues, and their abnormal expressions in various solid malignancies have been correlated with cancer cell growth, survival, or death. Recent evidence also highlights the mechanisms underlying the role of TRPMs in tumor epithelial-mesenchymal transition (EMT), autophagy, and cancer metabolic reprogramming. These implications support TRPM channels as potential molecular targets and their modulation as an innovative therapeutic approach against cancer. Here, we discuss the general characteristics of the different TRPMs, focusing on current knowledge about the connection between TRPM channels and critical features of cancer. We also cover TRPM modulators used as pharmaceutical tools in biological trials and an indication of the only clinical trial with a TRPM modulator about cancer. To conclude, the authors describe the prospects for TRPM channels in oncology.
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Affiliation(s)
- Tania Ciaglia
- Dipartimento di Farmacia (DIFARMA), Università degli Studi di Salerno, Fisciano, Italy
| | - Vincenzo Vestuto
- Dipartimento di Farmacia (DIFARMA), Università degli Studi di Salerno, Fisciano, Italy
| | - Alessia Bertamino
- Dipartimento di Farmacia (DIFARMA), Università degli Studi di Salerno, Fisciano, Italy
| | - Rosario González-Muñiz
- Departamento de Biomiméticos, Instituto de Química Médica, Madrid, Spain,*Correspondence: Isabel Gómez-Monterrey, ; Rosario González-Muñiz,
| | - Isabel Gómez-Monterrey
- Dipartimento di Farmacia, Università degli Studi di Napoli “Federico II”, Naples, Italy,*Correspondence: Isabel Gómez-Monterrey, ; Rosario González-Muñiz,
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9
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Ohkuma M, Maruyama T, Ishii T, Igarashi N, Azuma K, Inoue T, Obata R, Miyachi EI, Kaneda M. Effects of Progesterone and Other Gonadal Hormones on Glutamatergic Circuits in the Retina. J NIPPON MED SCH 2023; 90:333-345. [PMID: 37690823 DOI: 10.1272/jnms.jnms.2023_90-405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
BACKGROUND Gonadal hormones function in the retina; however, their targets have not yet been identified. Therefore, the present study examined the effects of progesterone and other gonadal hormones on glutamatergic circuits in the retina. METHODS Extracellular glutamate concentrations, which correspond to the amount of glutamate released, were examined using an enzyme-linked fluorescent assay system. The activity of glutamatergic synapses between bipolar cells and ganglion cells was investigated using a patch clamp technique. Changes in retinal thickness during pregnancy were assessed using optical coherence tomography (OCT) images. RESULTS Progesterone and pregnenolone sulfate increased extracellular glutamate concentrations, whereas estrogen and testosterone did not. Progesterone increased the activity of glutamatergic synapses between bipolar cells and ganglion cells. A temporal decrease in the thickness of the peripheral retina was observed in the 1st trimester. CONCLUSIONS Progesterone, but not estrogen or testosterone, activated glutamate release in the mouse retina. Increases in the concentration of progesterone during pregnancy did not induce any detectable change in retinal thickness.
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Affiliation(s)
| | - Takuma Maruyama
- Department of Physiology, Nippon Medical School
- Present address: Department of Physiology, Division of Neurophysiology, School of Medicine, Tokyo Women's Medical University
| | | | - Nozomi Igarashi
- Department of Ophthalmology, Faculty of Medicine, Tokyo University
| | - Keiko Azuma
- Department of Ophthalmology, Faculty of Medicine, Tokyo University
| | - Tatsuya Inoue
- Department of Ophthalmology, School of Medicine, Yokohama City University
| | - Ryo Obata
- Department of Ophthalmology, Faculty of Medicine, Tokyo University
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10
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Yadav P, Podia M, Kumari SP, Mani I. Glutamate receptor endocytosis and signaling in neurological conditions. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2023; 196:167-207. [PMID: 36813358 DOI: 10.1016/bs.pmbts.2022.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The non-essential amino acid glutamate acts as a major excitatory neurotransmitter and plays a significant role in the central nervous system (CNS). It binds with two different types of receptors, ionotropic glutamate receptors (iGluRs) and metabotropic glutamate receptors (mGluRs), responsible for the postsynaptic excitation of neurons. They are important for memory, neural development and communication, and learning. Endocytosis and subcellular trafficking of the receptor are essential for the regulation of receptor expression on the cell membrane and excitation of the cells. The endocytosis and trafficking of the receptor are dependent on its type, ligand, agonist, and antagonist present. This chapter discusses the types of glutamate receptors, their subtypes, and the regulation of their internalization and trafficking. The roles of glutamate receptors in neurological diseases are also briefly discussed.
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Affiliation(s)
- Prerna Yadav
- Department of Microbiology, University of Delhi, New Delhi, India
| | - Mansi Podia
- Department of Microbiology, University of Delhi, New Delhi, India
| | - Shashi Prabha Kumari
- Department of Microbiology, Ram Lal Anand College, University of Delhi, New Delhi, India
| | - Indra Mani
- Department of Microbiology, Gargi College, University of Delhi, New Delhi, India.
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11
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Križaj D, Cordeiro S, Strauß O. Retinal TRP channels: Cell-type-specific regulators of retinal homeostasis and multimodal integration. Prog Retin Eye Res 2023; 92:101114. [PMID: 36163161 PMCID: PMC9897210 DOI: 10.1016/j.preteyeres.2022.101114] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 08/03/2022] [Accepted: 08/08/2022] [Indexed: 02/05/2023]
Abstract
Transient receptor potential (TRP) channels are a widely expressed family of 28 evolutionarily conserved cationic ion channels that operate as primary detectors of chemical and physical stimuli and secondary effectors of metabotropic and ionotropic receptors. In vertebrates, the channels are grouped into six related families: TRPC, TRPV, TRPM, TRPA, TRPML, and TRPP. As sensory transducers, TRP channels are ubiquitously expressed across the body and the CNS, mediating critical functions in mechanosensation, nociception, chemosensing, thermosensing, and phototransduction. This article surveys current knowledge about the expression and function of the TRP family in vertebrate retinas, which, while dedicated to transduction and transmission of visual information, are highly susceptible to non-visual stimuli. Every retinal cell expresses multiple TRP subunits, with recent evidence establishing their critical roles in paradigmatic aspects of vertebrate vision that include TRPM1-dependent transduction of ON bipolar signaling, TRPC6/7-mediated ganglion cell phototransduction, TRP/TRPL phototransduction in Drosophila and TRPV4-dependent osmoregulation, mechanotransduction, and regulation of inner and outer blood-retina barriers. TRP channels tune light-dependent and independent functions of retinal circuits by modulating the intracellular concentration of the 2nd messenger calcium, with emerging evidence implicating specific subunits in the pathogenesis of debilitating diseases such as glaucoma, ocular trauma, diabetic retinopathy, and ischemia. Elucidation of TRP channel involvement in retinal biology will yield rewards in terms of fundamental understanding of vertebrate vision and therapeutic targeting to treat diseases caused by channel dysfunction or over-activation.
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Affiliation(s)
- David Križaj
- Departments of Ophthalmology, Neurobiology, and Bioengineering, University of Utah, Salt Lake City, USA
| | - Soenke Cordeiro
- Institute of Physiology, Faculty of Medicine, Christian-Albrechts-University Kiel, Germany
| | - Olaf Strauß
- Experimental Ophthalmology, Department of Ophthalmology, Charité - Universitätsmedizin Berlin, a Corporate Member of Freie Universität, Humboldt-University, The Berlin Institute of Health, Berlin, Germany.
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12
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Wilmet B, Callebert J, Duvoisin R, Goulet R, Tourain C, Michiels C, Frederiksen H, Schaeffel F, Marre O, Sahel JA, Audo I, Picaud S, Zeitz C. Mice Lacking Gpr179 with Complete Congenital Stationary Night Blindness Are a Good Model for Myopia. Int J Mol Sci 2022; 24:ijms24010219. [PMID: 36613663 PMCID: PMC9820543 DOI: 10.3390/ijms24010219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 12/13/2022] [Accepted: 12/14/2022] [Indexed: 12/25/2022] Open
Abstract
Mutations in GPR179 are one of the most common causes of autosomal recessive complete congenital stationary night blindness (cCSNB). This retinal disease is characterized in patients by impaired dim and night vision, associated with other ocular symptoms, including high myopia. cCSNB is caused by a complete loss of signal transmission from photoreceptors to ON-bipolar cells. In this study, we hypothesized that the lack of Gpr179 and the subsequent impaired ON-pathway could lead to myopic features in a mouse model of cCSNB. Using ultra performance liquid chromatography, we show that adult Gpr179-/- mice have a significant decrease in both retinal dopamine and 3,4-dihydroxyphenylacetic acid, compared to Gpr179+/+ mice. This alteration of the dopaminergic system is thought to be correlated with an increased susceptibility to lens-induced myopia but does not affect the natural refractive development. Altogether, our data added a novel myopia model, which could be used to identify therapeutic interventions.
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Affiliation(s)
- Baptiste Wilmet
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
- Correspondence: (B.W.); (C.Z.); Tel.: +33-1-53-46-25-26 (B.W.); +33-1-53-46-25-40 (C.Z.)
| | - Jacques Callebert
- Service of Biochemistry and Molecular Biology, INSERM U942, Hospital Lariboisière, AP-HP, 75010 Paris, France
| | - Robert Duvoisin
- Department of Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, OR 97239, USA
| | - Ruben Goulet
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
| | - Christophe Tourain
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
- Wavefront-Engineering Microscopy Group, Neurophotonics Laboratory, CNRS UMR8250, Paris Descartes University, 75270 Paris, France
| | - Christelle Michiels
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
| | - Helen Frederiksen
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
| | - Frank Schaeffel
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), 4056 Basel, Switzerland
- Section of Neurobiology of the Eye, Ophthalmic Research Institute, University of Tuebingen, 72076 Tuebingen, Germany
- Zeiss Vision Lab, Ophthalmic Research Institute, University of Tuebingen, 72076 Tuebingen, Germany
| | - Olivier Marre
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
| | - José Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
- Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, INSERM-DGOS CIC 1423, 75012 Paris, France
- Fondation Ophtalmologique Adolphe de Rothschild, 75019 Paris, France
- Académie des Sciences, Institut de France, 75006 Paris, France
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, INSERM-DGOS CIC 1423, 75012 Paris, France
| | - Serge Picaud
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
| | - Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, 75012 Paris, France
- Correspondence: (B.W.); (C.Z.); Tel.: +33-1-53-46-25-26 (B.W.); +33-1-53-46-25-40 (C.Z.)
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13
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Hung WC, Cheng HC, Wang AG. Melanoma-associated retinopathy with anti-TRPM1 autoantibodies showing concomitant Off-bipolar cell dysfunction. Doc Ophthalmol 2022; 145:263-270. [PMID: 36173494 DOI: 10.1007/s10633-022-09901-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 09/20/2022] [Indexed: 12/29/2022]
Abstract
BACKGROUND To report the clinical features of a patient with melanoma-associated retinopathy (MAR) with anti-transient receptor potential cation channel, subfamily M, member 1 (TRPM1) autoantibodies showing concomitant Off-bipolar cell dysfunction. METHODS We evaluated a patient with a past history of scalp melanoma presented with sudden-onset shimmering photopsia in both eyes. MAR was confirmed with complete ophthalmic examinations, electronegative electroretinogram (ERG), and the presence of anti-TRPM1 autoantibodies by Western blot analysis. S-cone ERG and photopic On-Off ERG were studied in this patient as well. RESULTS The patient's best-corrected visual acuity was 6/30 in the right eye and 6/8.6 in the left eye. Fundus and OCT findings were unremarkable. Visual field test showed severe constriction in both eyes. His full-field ERG was electronegative. S-cone ERG recorded preservation of L/M-cone-mediated response and undetectable S-cone-mediated response. Photopic On-Off ERG disclosed attenuated On- and Off-response. Western blot analysis confirmed immunoreactivity of the patient's serum to a 30 kDa TRPM1 recombinant protein. Whole-body positron emission tomography scan detected lymph node metastases in the neck. CONCLUSIONS Anti-TRPM1 autoantibody-positive MAR varies greatly in its presentation and clinical course. We present a case of anti-TRPM1 autoantibody-positive MAR with atypical feature of Off-bipolar cell involvement. A complete electroretinographic study together with identification of the pathogenic antiretinal autoantibodies may help better understand and subclassify the disease in the future.
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Affiliation(s)
- Wei-Che Hung
- Department of Ophthalmology, Taipei Veterans General Hospital, 201 Sec. 2, Shih-Pai Rd., Taipei, 11217, Taiwan
| | - Hui-Chen Cheng
- Department of Ophthalmology, Taipei Veterans General Hospital, 201 Sec. 2, Shih-Pai Rd., Taipei, 11217, Taiwan.,Department of Ophthalmology, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Program in Molecular Medicine, College of Life Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Department of Life Sciences and Institute of Genome Sciences, College of Life Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan.,Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - An-Guor Wang
- Department of Ophthalmology, Taipei Veterans General Hospital, 201 Sec. 2, Shih-Pai Rd., Taipei, 11217, Taiwan. .,Department of Ophthalmology, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan.
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14
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Bipolar cell targeted optogenetic gene therapy restores parallel retinal signaling and high-level vision in the degenerated retina. Commun Biol 2022; 5:1116. [PMID: 36266533 PMCID: PMC9585040 DOI: 10.1038/s42003-022-04016-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 09/21/2022] [Indexed: 11/09/2022] Open
Abstract
Optogenetic gene therapies to restore vision are in clinical trials. Whilst current clinical approaches target the ganglion cells, the output neurons of the retina, new molecular tools enable efficient targeting of the first order retinal interneurons, the bipolar cells, with the potential to restore a higher quality of vision. Here we investigate retinal signaling and behavioral vision in blind mice treated with bipolar cell targeted optogenetic gene therapies. All tested tools, including medium-wave opsin, Opto-mGluR6, and two new melanopsin based chimeras restored visual acuity and contrast sensitivity. The best performing opsin was a melanopsin-mGluR6 chimera, which in some cases restored visual acuities and contrast sensitivities that match wild-type animals. Light responses from the ganglion cells were robust with diverse receptive-field types, inferring elaborate inner retinal signaling. Our results highlight the potential of bipolar cell targeted optogenetics to recover high-level vision in human patients with end-stage retinal degenerations. A chimeric Mela(CTmGluR6) optogenetic tool has the potential to restore vision and signaling in a mouse model of degenerative retinal disease.
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15
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Scalabrino ML, Thapa M, Chew LA, Zhang E, Xu J, Sampath AP, Chen J, Field GD. Robust cone-mediated signaling persists late into rod photoreceptor degeneration. eLife 2022; 11:e80271. [PMID: 36040015 PMCID: PMC9560159 DOI: 10.7554/elife.80271] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 08/25/2022] [Indexed: 01/13/2023] Open
Abstract
Rod photoreceptor degeneration causes deterioration in the morphology and physiology of cone photoreceptors along with changes in retinal circuits. These changes could diminish visual signaling at cone-mediated light levels, thereby limiting the efficacy of treatments such as gene therapy for rescuing normal, cone-mediated vision. However, the impact of progressive rod death on cone-mediated signaling remains unclear. To investigate the fidelity of retinal ganglion cell (RGC) signaling throughout disease progression, we used a mouse model of rod degeneration (Cngb1neo/neo). Despite clear deterioration of cone morphology with rod death, cone-mediated signaling among RGCs remained surprisingly robust: spatiotemporal receptive fields changed little and the mutual information between stimuli and spiking responses was relatively constant. This relative stability held until nearly all rods had died and cones had completely lost well-formed outer segments. Interestingly, RGC information rates were higher and more stable for natural movies than checkerboard noise as degeneration progressed. The main change in RGC responses with photoreceptor degeneration was a decrease in response gain. These results suggest that gene therapies for rod degenerative diseases are likely to prolong cone-mediated vision even if there are changes to cone morphology and density.
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Affiliation(s)
- Miranda L Scalabrino
- Department of Neurobiology, Duke University School of MedicineDurhamUnited States
| | - Mishek Thapa
- Department of Neurobiology, Duke University School of MedicineDurhamUnited States
| | - Lindsey A Chew
- Department of Neurobiology, Duke University School of MedicineDurhamUnited States
| | - Esther Zhang
- Department of Neurobiology, Duke University School of MedicineDurhamUnited States
| | - Jason Xu
- Department of Statistical Science, Duke UniversityDurhamUnited States
| | - Alapakkam P Sampath
- Jules Stein Eye Institute, University of California, Los AngelesLos AngelesUnited States
| | - Jeannie Chen
- Zilkha Neurogenetics Institute, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - Greg D Field
- Department of Neurobiology, Duke University School of MedicineDurhamUnited States
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16
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Tsukamoto Y, Omi N. Multiple Invagination Patterns and Synaptic Efficacy in Primate and Mouse Rod Synaptic Terminals. Invest Ophthalmol Vis Sci 2022; 63:11. [PMID: 35819284 PMCID: PMC9287620 DOI: 10.1167/iovs.63.8.11] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Optical retina images are scaled based on eye size, which results in a linear scale ratio of 10:1 for human versus mouse and 7:1 for macaque monkey versus mouse. We examined how this scale difference correlates with the structural configuration of synaptic wiring in the rod spherule (RS) between macaque and mouse retinas compared with human data. Methods Rod bipolar cell (BC) dendrites and horizontal cell (HC) axonal processes, which invaginate the RS to form synaptic ribbon-associated triads, were examined by serial section transmission electron microscopy. Results The number of rod BC invaginating dendrites ranged 1∼4 in the macaque RS but only 1∼2 in the mouse. Approximately 40% of those dendrites bifurcated into two central elements in the macaque, but 2% of those dendrites did in the mouse. Both factors gave rise to 10 invagination patterns of BC and HC neurites in the macaque RS but only two in the mouse. Five morphological parameters: the lengths of arciform densities and ribbons, the area of the BC-RS contact, and the surface areas of BC and HC invaginating neurites, were all independent of the invagination patterns in the macaque RS. However, those parameters were significantly greater in the macaque than in the mouse by ratios of 1.5∼1.8. Conclusions The primate RS provides a more expansive BC-RS interface associated with the longer arciform density and more branched invaginating neurites of BCs and HCs than the mouse RS. The resulting greater synaptic contact area may contribute to more efficient signal transfer.
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Affiliation(s)
- Yoshihiko Tsukamoto
- Department of Biology, Hyogo College of Medicine, Mukogawa, Nishinomiya, Hyogo, Japan.,Studio EM-Retina, Satonaka, Nishinomiya, Hyogo, Japan.,Center for Systems Vision Science, Organization of Science and Technology, Ritsumeikan University, Kusatsu, Shiga, Japan
| | - Naoko Omi
- Studio EM-Retina, Satonaka, Nishinomiya, Hyogo, Japan
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17
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Inooka D, Omori Y, Ouchi N, Ohashi K, Kawakami Y, Koyanagi Y, Koike C, Terasaki H, Nishiguchi KM, Ueno S. Ablation of Ctrp9, Ligand of AdipoR1, and Lower Number of Cone Photoreceptors in Mouse Retina. Invest Ophthalmol Vis Sci 2022; 63:14. [PMID: 35575905 PMCID: PMC9123514 DOI: 10.1167/iovs.63.5.14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 04/26/2022] [Indexed: 11/24/2022] Open
Abstract
Purpose C1q/TNF-related protein (CTRP) 9 is one of the adiponectin paralogs, and a genetic ablation of its receptor, AdipoR1, is known to cause retinal degeneration. The purpose of this study was to determine the role played by CTRP9 in the retina. Methods The retinas of Ctrp9 gene knockout (KO) and wild type (WT) mice were examined by electroretinography (ERG), histology, RNA sequencing, and quantitative real-time PCR. Results The amplitude of the photopic ERG elicited by the maximum stimulus intensity was smaller by 40% in the Ctrp9 KO mice than in WT mice at 8 weeks of age. However, the photopic ERGs was not reduced from 8 weeks to 6 months of age. The amplitudes of the scotopic ERGs were not reduced in the Ctrp9 KO mice at 8 weeks and 6 months of age. No distinct histological abnormalities were found in the retinal sections but the density of peanut agglutinin-stained cells in the retinal flat mount of KO mice was reduced to about 70% of that of WT mice. Genomewide RNA sequencing of the retina revealed the absence of the expression of CTRP9 in both KO and WT mice. RNA sequencing and quantitative real-time PCR analysis showed that the expressions of the transcripts of genes expressed in cones, Opn1sw, Opn1mw, Gnat2, and Cnga3, were reduced in the KO mice retina, however, the degree of expression of the transcripts in rods was not significantly reduced. Conclusions CTRP9 is released ectopically from other tissues, and it regulates the number of cones in the mouse retinas.
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Affiliation(s)
- Daiki Inooka
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yoshihiro Omori
- Laboratory of Functional Genomics, Graduate School of Bioscience, Nagahama Institute of Bioscience and Technology, Shiga, Japan
| | - Noriyuki Ouchi
- Department of Molecular Medicine and Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Koji Ohashi
- Department of Molecular Medicine and Cardiology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuto Kawakami
- Laboratory of Functional Genomics, Graduate School of Bioscience, Nagahama Institute of Bioscience and Technology, Shiga, Japan
| | - Yoshito Koyanagi
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Department of Ophthalmology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Chieko Koike
- College of Pharmaceutical Sciences, Ritsumeikan University, Kusatsu, Shiga, Japan
| | - Hiroko Terasaki
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Koji M. Nishiguchi
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Shinji Ueno
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Nagoya, Japan
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18
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Role of TRPM2 in brain tumours and potential as a drug target. Acta Pharmacol Sin 2022; 43:759-770. [PMID: 34108651 DOI: 10.1038/s41401-021-00679-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 04/07/2021] [Indexed: 02/06/2023] Open
Abstract
Ion channels are ubiquitously expressed in almost all living cells, and are the third-largest category of drug targets, following enzymes and receptors. The transient receptor potential melastatin (TRPM) subfamily of ion channels are important to cell function and survival. Studies have shown upregulation of the TRPM family of ion channels in various brain tumours. Gliomas are the most prevalent form of primary malignant brain tumours with no effective treatment; thus, drug development is eagerly needed. TRPM2 is an essential ion channel for cell function and has important roles in oxidative stress and inflammation. In response to oxidative stress, ADP-ribose (ADPR) is produced, and in turn activates TRPM2 by binding to the NUDT9-H domain on the C-terminal. TRPM2 has been implicated in various cancers and is significantly upregulated in brain tumours. This article reviews the current understanding of TRPM2 in the context of brain tumours and overviews the effects of potential drug therapies targeting TRPM2 including hydrogen peroxide (H2O2), curcumin, docetaxel and selenium, paclitaxel and resveratrol, and botulinum toxin. It is long withstanding knowledge that gliomas are difficult to treat effectively, therefore investigating TRPM2 as a potential therapeutic target for brain tumours may be of considerable interest in the fields of ion channels and pharmacology.
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19
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Souza Bomfim GH, Niemeyer BA, Lacruz RS, Lis A. On the Connections between TRPM Channels and SOCE. Cells 2022; 11:1190. [PMID: 35406753 PMCID: PMC8997886 DOI: 10.3390/cells11071190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/23/2022] [Accepted: 03/30/2022] [Indexed: 12/02/2022] Open
Abstract
Plasma membrane protein channels provide a passageway for ions to access the intracellular milieu. Rapid entry of calcium ions into cells is controlled mostly by ion channels, while Ca2+-ATPases and Ca2+ exchangers ensure that cytosolic Ca2+ levels ([Ca2+]cyt) are maintained at low (~100 nM) concentrations. Some channels, such as the Ca2+-release-activated Ca2+ (CRAC) channels and voltage-dependent Ca2+ channels (CACNAs), are highly Ca2+-selective, while others, including the Transient Receptor Potential Melastatin (TRPM) family, have broader selectivity and are mostly permeable to monovalent and divalent cations. Activation of CRAC channels involves the coupling between ORAI1-3 channels with the endoplasmic reticulum (ER) located Ca2+ store sensor, Stromal Interaction Molecules 1-2 (STIM1/2), a pathway also termed store-operated Ca2+ entry (SOCE). The TRPM family is formed by 8 members (TRPM1-8) permeable to Mg2+, Ca2+, Zn2+ and Na+ cations, and is activated by multiple stimuli. Recent studies indicated that SOCE and TRPM structure-function are interlinked in some instances, although the molecular details of this interaction are only emerging. Here we review the role of TRPM and SOCE in Ca2+ handling and highlight the available evidence for this interaction.
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Affiliation(s)
- Guilherme H. Souza Bomfim
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY 10010, USA;
| | - Barbara A. Niemeyer
- Department of Molecular Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, 66421 Homburg, Germany;
| | - Rodrigo S. Lacruz
- Department of Molecular Pathobiology, New York University College of Dentistry, New York, NY 10010, USA;
| | - Annette Lis
- Department of Biophysics, Center for Integrative Physiology and Molecular Medicine, School of Medicine, Saarland University, 66421 Homburg, Germany
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20
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Miyadera K, Santana E, Roszak K, Iffrig S, Visel M, Iwabe S, Boyd RF, Bartoe JT, Sato Y, Gray A, Ripolles-Garcia A, Dufour VL, Byrne LC, Flannery JG, Beltran WA, Aguirre GD. Targeting ON-bipolar cells by AAV gene therapy stably reverses LRIT3-congenital stationary night blindness. Proc Natl Acad Sci U S A 2022; 119:e2117038119. [PMID: 35316139 PMCID: PMC9060458 DOI: 10.1073/pnas.2117038119] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 01/10/2022] [Indexed: 01/08/2023] Open
Abstract
SignificanceCanine models of inherited retinal diseases have helped advance adeno-associated virus (AAV)-based gene therapies targeting specific cells in the outer retina for treating blinding diseases in patients. However, therapeutic targeting of diseases such as congenital stationary night blindness (CSNB) that exhibit defects in ON-bipolar cells (ON-BCs) of the midretina remains underdeveloped. Using a leucine-rich repeat, immunoglobulin-like and transmembrane domain 3 (LRIT3) mutant canine model of CSNB exhibiting ON-BC dysfunction, we tested the ability of cell-specific AAV capsids and promotors to specifically target ON-BCs for gene delivery. Subretinal injection of one vector demonstrated safety and efficacy with robust and stable rescue of electroretinography signals and night vision up to 1 y, paving the way for clinical trials in patients.
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Affiliation(s)
- Keiko Miyadera
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Evelyn Santana
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Karolina Roszak
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Sommer Iffrig
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Meike Visel
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - Simone Iwabe
- Ophthalmology Services, Charles River Laboratories, Mattawan, MI 49071
| | - Ryan F. Boyd
- Ophthalmology Services, Charles River Laboratories, Mattawan, MI 49071
| | - Joshua T. Bartoe
- Ophthalmology Services, Charles River Laboratories, Mattawan, MI 49071
| | - Yu Sato
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Alexa Gray
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Ana Ripolles-Garcia
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Valérie L. Dufour
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Leah C. Byrne
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - John G. Flannery
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - William A. Beltran
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Gustavo D. Aguirre
- Division of Experimental Retinal Therapies, Department of Clinical Sciences & Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104
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21
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Hsieh CC, Su YC, Jiang KY, Ito T, Li TW, Kaku-Ito Y, Cheng ST, Chen LT, Hwang DY, Shen CH. TRPM1 promotes tumor progression in acral melanoma by activating the Ca 2+/CaMKIIδ/AKT pathway. J Adv Res 2022; 43:45-57. [PMID: 36585114 PMCID: PMC9811324 DOI: 10.1016/j.jare.2022.03.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/27/2022] [Accepted: 03/02/2022] [Indexed: 01/07/2023] Open
Abstract
INTRODUCTION Acral melanoma is a predominant and aggressive subtype of melanoma in non-Caucasian populations. There is a lack of genotype-driven therapies for over 50% of patients. TRPM1 (transient receptor potential melastatin 1), a nonspecific cation channel, is mainly expressed in retinal bipolar neurons and skin. Nonetheless, the function of TRPM1 in melanoma progression is poorly understood. OBJECTIVES We investigated the association between TRPM1 and acral melanoma progression and revealed the molecular mechanisms by which TRPM1 promotes tumor progression and malignancy. METHODS TRPM1 expression and CaMKII phosphorylation in tumor specimens were tested by immunohistochemistry analysis and scored by two independent investigators. The functions of TRPM1 and CaMKII were assessed using loss-of-function and gain-of-function approaches and examined by western blotting, colony formation, cell migration and invasion, and xenograft tumor growth assays. The effects of a CaMKII inhibitor, KN93, were evaluated using both in vitro cell and in vivo xenograft mouse models. RESULTS We revealed that TRPM1 protein expression was positively associated with tumor progression and shorter survival in patients with acral melanoma. TRPM1 promoted AKT activation and the colony formation, cell mobility, and xenograft tumor growth of melanoma cells. TRPM1 elevated cytosolic Ca2+ levels and activated CaMKIIδ (Ca2+/calmodulin-dependent protein kinase IIδ) to promote the CaMKIIδ/AKT interaction and AKT activation. The functions of TRPM1 in melanoma cells were suppressed by a CaMKII inhibitor, KN93. Significant upregulation of phospho-CaMKII levels in acral melanomas was related to increased expression of TRPM1. An acral melanoma cell line with high expression of TRPM1, CA11, was isolated from a patient to show the anti-tumor activity of KN93 in vitro and in vivo. CONCLUSIONS TRPM1 promotes tumor progression and malignancy in acral melanoma by activating the Ca2+/CaMKIIδ/AKT pathway. CaMKII inhibition may be a potential therapeutic strategy for treating acral melanomas with high expression of TRPM1.
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Affiliation(s)
- Chi-Che Hsieh
- National Institute of Cancer Research, National Health Research Institutes, Tainan 704, Taiwan
| | - Yue-Chiu Su
- Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Kuan-Ying Jiang
- National Institute of Cancer Research, National Health Research Institutes, Tainan 704, Taiwan
| | - Takamichi Ito
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Ting-Wei Li
- Department of Life Sciences, National Cheng Kung University, Tainan 704, Taiwan
| | - Yumiko Kaku-Ito
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
| | - Shih-Tsung Cheng
- Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan,Department of Dermatology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan,Department of Dermatology, College of Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Li-Tzong Chen
- National Institute of Cancer Research, National Health Research Institutes, Tainan 704, Taiwan,Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 807, Taiwan,Center for Cancer Research, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Daw-Yang Hwang
- National Institute of Cancer Research, National Health Research Institutes, Tainan 704, Taiwan
| | - Che-Hung Shen
- National Institute of Cancer Research, National Health Research Institutes, Tainan 704, Taiwan,Ph.D. Program in Tissue Engineering and Regenerative Medicine, Biotechnology Center, National Chung Hsing University, Taichung 402, Taiwan,Corresponding author at: National Institute of Cancer Research, National Health Research Institutes, No. 367, Sheng-Li Rd., North District, Tainan 70456, Taiwan.
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22
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Palazzo E, Boccella S, Marabese I, Perrone M, Belardo C, Iannotta M, Scuteri D, De Dominicis E, Pagano M, Infantino R, Bagetta G, Maione S. Homo-AMPA in the periaqueductal grey modulates pain and rostral ventromedial medulla activity in diabetic neuropathic mice. Neuropharmacology 2022; 212:109047. [DOI: 10.1016/j.neuropharm.2022.109047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 02/22/2022] [Accepted: 03/26/2022] [Indexed: 12/21/2022]
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23
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Kovermann P, Engels M, Müller F, Fahlke C. Cellular Physiology and Pathophysiology of EAAT Anion Channels. Front Cell Neurosci 2022; 15:815279. [PMID: 35087380 PMCID: PMC8787812 DOI: 10.3389/fncel.2021.815279] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 12/13/2021] [Indexed: 11/17/2022] Open
Abstract
Excitatory amino acid transporters (EAATs) optimize the temporal resolution and energy demand of mammalian excitatory synapses by quickly removing glutamate from the synaptic cleft into surrounding neuronal and glial cells and ensuring low resting glutamate concentrations. In addition to secondary active glutamate transport, EAATs also function as anion channels. The channel function of these transporters is conserved in all homologs ranging from archaebacteria to mammals; however, its physiological roles are insufficiently understood. There are five human EAATs, which differ in their glutamate transport rates. Until recently the high-capacity transporters EAAT1, EAAT2, and EAAT3 were believed to conduct only negligible anion currents, with no obvious function in cell physiology. In contrast, the low-capacity glutamate transporters EAAT4 and EAAT5 are thought to regulate neuronal signaling as glutamate-gated channels. In recent years, new experimental approaches and novel animal models, together with the discovery of a human genetic disease caused by gain-of-function mutations in EAAT anion channels have enabled identification of the first physiological and pathophysiological roles of EAAT anion channels.
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24
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Ichinose T, Habib S. ON and OFF Signaling Pathways in the Retina and the Visual System. FRONTIERS IN OPHTHALMOLOGY 2022; 2:989002. [PMID: 36926308 PMCID: PMC10016624 DOI: 10.3389/fopht.2022.989002] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Visual processing starts at the retina of the eye, and signals are then transferred primarily to the visual cortex and the tectum. In the retina, multiple neural networks encode different aspects of visual input, such as color and motion. Subsequently, multiple neural streams in parallel convey unique aspects of visual information to cortical and subcortical regions. Bipolar cells, which are the second order neurons of the retina, separate visual signals evoked by light and dark contrasts and encode them to ON and OFF pathways, respectively. The interplay between ON and OFF neural signals is the foundation for visual processing for object contrast which underlies higher order stimulus processing. ON and OFF pathways have been classically thought to signal in a mirror-symmetric manner. However, while these two pathways contribute synergistically to visual perception in some instances, they have pronounced asymmetries suggesting independent operation in other cases. In this review, we summarize the role of the ON-OFF dichotomy in visual signaling, aiming to contribute to the understanding of visual recognition.
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Affiliation(s)
- Tomomi Ichinose
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, USA
- Correspondence: Tomomi Ichinose, MD, PhD,
| | - Samar Habib
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, Michigan, USA
- Department of Medical Parasitology, Mansoura Faculty of Medicine, Mansoura University, Mansoura, Egypt
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25
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Chambers S, Leftwich T, Pamonag M, Rice J, Walker MT. Trpm1: Novel function at the intersection of light and pain response in the iris. Exp Eye Res 2021; 215:108897. [PMID: 34954202 DOI: 10.1016/j.exer.2021.108897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 12/06/2021] [Accepted: 12/09/2021] [Indexed: 11/16/2022]
Abstract
In mammals, the retina is the photosensitive tissue that is responsible for the capture of light and the transduction of the light-initiated signals to the brain. These visual signals help to drive image and non-image forming behaviors. The pupillary light reflex (PLR) is an involuntary non-image forming behavior which involves the constriction of the iris muscle tissue in response to ambient light intensity. A subset of photosensitive retinal ganglion cells provides the principal pathway for all light input to the olivary pretectal nucleus which directs the neuronal input to drive iris constriction. Transient receptor potential melastatin 1 (Trpm1) knockout mice have a severe defect in PLR, but it remains unclear how the Trpm1 channel contributes to this behavior. We have demonstrated that the reduced PLR in Trpm1-/- mice at scotopic and photopic intensities is due to a functional loss of Trpm1 in the retina as well as the iris sphincter muscle. We have also tested constriction in isolated eyes and have shown that light-driven constriction independent of signaling from the brain also requires Trpm1 expression. In both the in vivo PLR and the iris photomechanical response, melanopsin is required for the light-dependent activation. Finally, pharmacological experiments using capsaicin to activate pain afferents in the eye demonstrate that Trpm1 expression is required for all sensory driven iris constriction. Our results demonstrate for the first time that Trpm1 has a novel and necessary role in iridial cells and is required for all sensory-driven constriction in the iris.
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Affiliation(s)
- Shane Chambers
- Department of Biology, James Madison University, Harrisonburg, VA, 22807, USA
| | - Tess Leftwich
- Department of Biology, James Madison University, Harrisonburg, VA, 22807, USA
| | - Michael Pamonag
- Department of Biology, James Madison University, Harrisonburg, VA, 22807, USA
| | - Jeremy Rice
- Department of Biology, James Madison University, Harrisonburg, VA, 22807, USA
| | - Marquis T Walker
- Department of Biology, James Madison University, Harrisonburg, VA, 22807, USA.
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26
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Agosto MA, Adeosun AAR, Kumar N, Wensel TG. The mGluR6 ligand-binding domain, but not the C-terminal domain, is required for synaptic localization in retinal ON-bipolar cells. J Biol Chem 2021; 297:101418. [PMID: 34793838 PMCID: PMC8671642 DOI: 10.1016/j.jbc.2021.101418] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 11/03/2021] [Accepted: 11/08/2021] [Indexed: 11/26/2022] Open
Abstract
Signals from retinal photoreceptors are processed in two parallel channels—the ON channel responds to light increments, while the OFF channel responds to light decrements. The ON pathway is mediated by ON type bipolar cells (BCs), which receive glutamatergic synaptic input from photoreceptors via a G-protein-coupled receptor signaling cascade. The metabotropic glutamate receptor mGluR6 is located at the dendritic tips of all ON-BCs and is required for synaptic transmission. Thus, it is critically important for delivery of information from photoreceptors into the ON pathway. In addition to detecting glutamate, mGluR6 participates in interactions with other postsynaptic proteins, as well as trans-synaptic interactions with presynaptic ELFN proteins. Mechanisms of mGluR6 synaptic targeting and functional interaction with other synaptic proteins are unknown. Here, we show that multiple regions in the mGluR6 ligand-binding domain are necessary for both synaptic localization in BCs and ELFN1 binding in vitro. However, these regions were not required for plasma membrane localization in heterologous cells, indicating that secretory trafficking and synaptic localization are controlled by different mechanisms. In contrast, the mGluR6 C-terminus was dispensable for synaptic localization. In mGluR6 null mice, localization of the postsynaptic channel protein TRPM1 was compromised. Introducing WT mGluR6 rescued TRPM1 localization, while a C-terminal deletion mutant had significantly reduced rescue ability. We propose a model in which trans-synaptic ELFN1 binding is necessary for mGluR6 postsynaptic localization, whereas the C-terminus has a role in mediating TRPM1 trafficking. These findings reveal different sequence determinants of the multifunctional roles of mGluR6 in ON-BCs.
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Affiliation(s)
- Melina A Agosto
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston TX, USA.
| | - Abiodun Adefola R Adeosun
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston TX, USA; Pharmacology and Chemical Biology Graduate Program, Baylor College of Medicine, Houston TX, USA
| | - Nitin Kumar
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston TX, USA
| | - Theodore G Wensel
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston TX, USA; Pharmacology and Chemical Biology Graduate Program, Baylor College of Medicine, Houston TX, USA
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27
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Young BK, Ramakrishnan C, Ganjawala T, Wang P, Deisseroth K, Tian N. An uncommon neuronal class conveys visual signals from rods and cones to retinal ganglion cells. Proc Natl Acad Sci U S A 2021; 118:e2104884118. [PMID: 34702737 PMCID: PMC8612366 DOI: 10.1073/pnas.2104884118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2021] [Indexed: 01/01/2023] Open
Abstract
Neurons in the central nervous system (CNS) are distinguished by the neurotransmitter types they release, their synaptic connections, morphology, and genetic profiles. To fully understand how the CNS works, it is critical to identify all neuronal classes and reveal their synaptic connections. The retina has been extensively used to study neuronal development and circuit formation. Here, we describe a previously unidentified interneuron in mammalian retina. This interneuron shares some morphological, physiological, and molecular features with retinal bipolar cells, such as receiving input from photoreceptors and relaying visual signals to retinal ganglion cells. It also shares some features with amacrine cells (ACs), particularly Aii-ACs, such as their neurite morphology in the inner plexiform layer, the expression of some AC-specific markers, and possibly the release of the inhibitory neurotransmitter glycine. Thus, we unveil an uncommon interneuron, which may play an atypical role in vision.
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Affiliation(s)
- Brent K Young
- Department of Ophthalmology & Visual Sciences, University of Utah, Salt Lake City, UT 84132
- Interdepartmental Neuroscience Program, University of Utah, Salt Lake City, UT 84114
| | | | - Tushar Ganjawala
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI 48202
| | - Ping Wang
- Department of Ophthalmology & Visual Sciences, University of Utah, Salt Lake City, UT 84132
| | - Karl Deisseroth
- Department of Bioengineering, Stanford University, Stanford, CA 94305
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305
| | - Ning Tian
- Department of Ophthalmology & Visual Sciences, University of Utah, Salt Lake City, UT 84132;
- Interdepartmental Neuroscience Program, University of Utah, Salt Lake City, UT 84114
- Department of Neurobiology, University of Utah, Salt Lake City, UT 84132
- Department of Biomedical Engineering, University of Utah, Salt Lake City, UT 84132
- Veterans Affairs Medical Center, Salt Lake City, UT 84148
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28
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Grabner CP, Moser T. The mammalian rod synaptic ribbon is essential for Ca v channel facilitation and ultrafast synaptic vesicle fusion. eLife 2021; 10:63844. [PMID: 34617508 PMCID: PMC8594941 DOI: 10.7554/elife.63844] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 10/06/2021] [Indexed: 12/19/2022] Open
Abstract
Rod photoreceptors (PRs) use ribbon synapses to transmit visual information. To signal ‘no light detected’ they release glutamate continually to activate post-synaptic receptors. When light is detected glutamate release pauses. How a rod’s individual ribbon enables this process was studied here by recording evoked changes in whole-cell membrane capacitance from wild-type and ribbonless (Ribeye-ko) mice. Wild-type rods filled with high (10 mM) or low (0.5 mM) concentrations of the Ca2+-buffer EGTA created a readily releasable pool (RRP) of 87 synaptic vesicles (SVs) that emptied as a single kinetic phase with a τ<0.4 ms. The lower concentration of EGTA accelerated Cav channel opening and facilitated release kinetics. In contrast, ribbonless rods created a much smaller RRP of 22 SVs, and they lacked Cav channel facilitation; however, Ca2+ channel-release coupling remained tight. These release deficits caused a sharp attenuation of rod-driven scotopic light responses. We conclude that the synaptic ribbon facilitates Ca2+-influx and establishes a large RRP of SVs.
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Affiliation(s)
- Chad Paul Grabner
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, Göttingen, Germany.,Synaptic Nanophysiology Group, Max Planck Institute of Biophysical Chemistry, Göttingen, Germany.,Collaborative Research Center 1286 'Quantitative Synaptology', University of Göttingen, Göttingen, Germany
| | - Tobias Moser
- Institute for Auditory Neuroscience and InnerEarLab, University Medical Center Göttingen, Göttingen, Germany.,Synaptic Nanophysiology Group, Max Planck Institute of Biophysical Chemistry, Göttingen, Germany.,Collaborative Research Center 1286 'Quantitative Synaptology', University of Göttingen, Göttingen, Germany.,Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, Göttingen, Germany
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29
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Gyoten D, Ueno S, Okado S, Chaya T, Yasuda S, Morimoto T, Kondo M, Kimura K, Hayashi T, Leroy BP, Woo SJ, Mukai R, Joo K, Furukawa T. Broad locations of antigenic regions for anti-TRPM1 autoantibodies in paraneoplastic retinopathy with retinal ON bipolar cell dysfunction. Exp Eye Res 2021; 212:108770. [PMID: 34562437 DOI: 10.1016/j.exer.2021.108770] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 08/06/2021] [Accepted: 09/13/2021] [Indexed: 11/24/2022]
Abstract
PURPOSE Cancer-associated retinal ON bipolar cell dysfunction (CARBD), which includes melanoma-associated retinopathy (MAR), has been reported to be caused by autoantibodies against the molecules expressed in ON bipolar cells, including TRPM1. The purpose of this study was to determine the antigenic regions of the autoantibodies against TRPM1 in the sera of CARBD patients, in whom we previously detected anti-TRPM1 autoantibodies. METHODS The antigenic regions against TRPM1 in the sera of eight CARBD patients were examined by Western blots using HEK293T cells transfected with the plasmids expressing FLAG-tagged TRPM1 fragments. The clinical course of these patients was also documented. RESULTS The clinical course differed among the patients. The electroretinograms (ERGs) and symptoms were improved in three patients, deteriorated in one patient, remained unchanged for a long time in one patient, and were not followable in three patients. Seven of the eight sera possessed multiple antigenic regions: two sera contained at least four antigen recognition regions, and three sera had at least three regions. The antigen regions were spread over the entire TRPM1 protein: five sera in the N-terminal intracellular domain, six sera in the transmembrane-containing region, and six sera in the C-terminal intracellular domain. No significant relationship was observed between the location of the antigen epitope and the patients' clinical course. CONCLUSIONS The antigenic regions of anti-TRPM1 autoantibodies in CARBD patients were present not only in the N-terminal intracellular domain, which was reported in an earlier report, but also in the transmembrane-containing region and in the C-terminal intracellular domain. In addition, the antigenic regions for TRPM1 were found to vary among the CARBD patients examined, and most of the sera had multiple antigenic regions.
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Affiliation(s)
- Daichi Gyoten
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, Osaka, Japan
| | - Shinji Ueno
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Aichi, Japan.
| | - Satoshi Okado
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Aichi, Japan
| | - Taro Chaya
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, Osaka, Japan
| | - Shunsuke Yasuda
- Department of Ophthalmology, Nagoya University Graduate School of Medicine, Aichi, Japan
| | - Takeshi Morimoto
- Department of Advanced Visual Neuroscience, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Mineo Kondo
- Department of Ophthalmology, Mie University Graduate School of Medicine, Mie, Japan
| | - Kazuhiro Kimura
- Department of Ophthalmology, Yamaguchi University Graduate School of Medicine, Yamaguchi, Japan
| | - Takaaki Hayashi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Bart P Leroy
- Department of Ophthalmology, Ghent University Hospital, Ghent University, Ghent, Belgium; Department of Ophthalmology, Center for Medical Genetics, Ghent University Hospital, Ghent University, Ghent, Belgium; Division of Ophthalmology and CCMT, The Children's Hospital of Philadelphia, Philadelphia, USA
| | - Se Joon Woo
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Ryo Mukai
- Department of Ophthalmology, Gunma University Graduate School of Medicine, Gunma, Japan
| | - Kwangsic Joo
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Takahisa Furukawa
- Laboratory for Molecular and Developmental Biology, Institute for Protein Research, Osaka University, Osaka, Japan
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30
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Clinical Findings of Melanoma-Associated Retinopathy with anti-TRPM1 Antibody. Case Rep Ophthalmol Med 2021; 2021:6607441. [PMID: 34540301 PMCID: PMC8445719 DOI: 10.1155/2021/6607441] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 08/27/2021] [Indexed: 11/29/2022] Open
Abstract
Introduction We report the clinical features and clinical course of melanoma-associated retinopathy (MAR), in which autoantibodies against the transient receptor potential cation channel subfamily M member 1 (TRPM1) were detected. Case Presentation. A 74-year-old man was referred to our hospital for treatment of bilateral vision loss. The best-corrected visual acuity was 20/100 in the right eye and 20/200 in the left eye. His electroretinogram (ERG) showed a reduced b-wave and a normal dark-adapted a-wave in both eyes. Optical coherence tomography (OCT) revealed loss of the interdigitation zone in both eyes. We strongly suspected MAR based on the markedly reduced b-wave in the ERG and a history of intranasal melanoma. The diagnosis was confirmed after autoantibodies against TRPM1 were detected in his blood serum. Fifteen months later, his ERG remained unchanged, and OCT showed bilateral cystic changes in the internal nuclear layer. The visual acuity in both eyes also remained unchanged. Conclusions Anti-TRPM1 autoantibodies were detected in a patient diagnosed with MAR who had negative flash ERG and retinal microstructural abnormalities, and the impairment did not recover during the follow-up period. Identification of anti-TRPM1 antibodies was helpful in confirming the diagnosis of MAR.
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Abstract
Background Ocular adverse events are common dose-limiting toxicities in cancer patients treated with HSP90 inhibitors, such as AUY922; however, the pathology and molecular mechanisms that mediate AUY922-induced retinal toxicity remain undescribed. Methods The impact of AUY922 on mouse retinas and cell lines was comprehensively investigated using isobaric tags for relative and absolute quantitation (iTRAQ)‑based proteomic profiling and pathway enrichment analysis, immunohistochemistry and immunofluorescence staining, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, MTT assay, colony formation assay, and western blot analysis. The effect of AUY922 on the Transient Receptor Potential cation channel subfamily M member 1 (TRPM1)-HSP90 chaperone complex was characterized by coimmunoprecipitation. TRPM1-regulated gene expression was analyzed by RNAseq analysis and gene set enrichment analysis (GSEA). The role of TRPM1 was assessed using both loss-of-function and gain-of-function approaches. Results Here, we show that the treatment with AUY922 induced retinal damage and cell apoptosis, dysregulated the photoreceptor and retinal pigment epithelium (RPE) layers, and reduced TRPM1 expression. Proteomic profiling and functional annotation of differentially expressed proteins reveals that those related to stress responses, protein folding processes, regulation of apoptosis, cell cycle and growth, reactive oxygen species (ROS) response, cell junction assembly and adhesion regulation, and proton transmembrane transport were significantly enriched in AUY922-treated cells. We found that AUY922 triggered caspase-3-dependent cell apoptosis, increased ROS production and inhibited cell growth. We determined that TRPM1 is a bona fide HSP90 client and characterized that AUY922 may reduce TRPM1 expression by disrupting the CDC37-HSP90 chaperone complex. Additionally, GSEA revealed that TRPM1-regulated genes were associated with retinal morphogenesis in camera-type eyes and the JAK-STAT cascade. Finally, gain-of-function and loss-of-function analyses validated the finding that TRPM1 mediated the cell apoptosis, ROS production and growth inhibition induced by AUY922. Conclusions Our study demonstrates the pathology of AUY922-induced retinal toxicity in vivo. TRPM1 is an HSP90 client, regulates photoreceptor morphology and function, and mediates AUY922-induced cytotoxicity. Supplementary Information The online version contains supplementary material available at 10.1186/s12929-021-00751-5.
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Abstract
The transient receptor potential (TRP) channel superfamily consists of a large group of non-selective cation channels that serve as cellular sensors for a wide spectrum of physical and environmental stimuli. The 28 mammalian TRPs, categorized into six subfamilies, including TRPC (canonical), TRPV (vanilloid), TRPM (melastatin), TRPA (ankyrin), TRPML (mucolipin) and TRPP (polycystin), are widely expressed in different cells and tissues. TRPs exhibit a variety of unique features that not only distinguish them from other superfamilies of ion channels, but also confer diverse physiological functions. Located at the plasma membrane or in the membranes of intracellular organelles, TRPs are the cellular safeguards that sense various cell stresses and environmental stimuli and translate this information into responses at the organismal level. Loss- or gain-of-function mutations of TRPs cause inherited diseases and pathologies in different physiological systems, whereas up- or down-regulation of TRPs is associated with acquired human disorders. In this Cell Science at a Glance article and the accompanying poster, we briefly summarize the history of the discovery of TRPs, their unique features, recent advances in the understanding of TRP activation mechanisms, the structural basis of TRP Ca2+ selectivity and ligand binding, as well as potential roles in mammalian physiology and pathology.
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Affiliation(s)
- Lixia Yue
- Calhoun Cardiology Center, Department of Cell Biology, University of Connecticut School of Medicine (UConn Health), Farmington, CT 06030, USA
| | - Haoxing Xu
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
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33
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Shi R, Fu Y, Zhao D, Boczek T, Wang W, Guo F. Cell death modulation by transient receptor potential melastatin channels TRPM2 and TRPM7 and their underlying molecular mechanisms. Biochem Pharmacol 2021; 190:114664. [PMID: 34175300 DOI: 10.1016/j.bcp.2021.114664] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/21/2021] [Accepted: 06/22/2021] [Indexed: 10/21/2022]
Abstract
Transient receptor potential melastatin (TRPM) channels are members of the transient receptor potential (TRP) channels, a family of evolutionarily conserved integral membrane proteins. TRPM channels are nonselective cation channels, mediating the influx of various ions including Ca2+, Na+ and Zn2+. The function of TRPM channels is vital for cell proliferation, cell development and cell death. Cell death is a key procedure during embryonic development, organism homeostasis, aging and disease. The category of cell death modalities, beyond the traditionally defined concepts of necrosis, autophagy, and apoptosis, were extended with the discovery of pyroptosis, necroptosis and ferroptosis. As upstream signaling regulators of cell death, TRPM channels have been involved inrelevant pathologies. In this review, we introduced several cell death modalities, then summarized the contribution of TRPM channels (especially TRPM2 and TRPM7) to different cell death modalities and discussed the underlying regulatory mechanisms. Our work highlighted the possibility of TRPM channels as potential therapeutic targets in cell death-related diseases.
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Affiliation(s)
- Ruixue Shi
- Department of Pharmaceutical Toxicology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Yu Fu
- Department of Pharmaceutical Toxicology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Dongyi Zhao
- The University of Tokyo, Department of Pharmaceutical Science, 1130033, Japan
| | - Tomasz Boczek
- Department of Molecular Neurochemistry, Medical University of Lodz, 92215, Poland.
| | - Wuyang Wang
- Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou 221004, China.
| | - Feng Guo
- Department of Pharmaceutical Toxicology, School of Pharmacy, China Medical University, Shenyang 110122, China.
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Pang JJ, Gao F, Wu SM. Generators of Pressure-Evoked Currents in Vertebrate Outer Retinal Neurons. Cells 2021; 10:cells10061288. [PMID: 34067375 PMCID: PMC8224636 DOI: 10.3390/cells10061288] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/13/2021] [Accepted: 05/19/2021] [Indexed: 12/19/2022] Open
Abstract
(1) Background: High-tension glaucoma damages the peripheral vision dominated by rods. How mechanosensitive channels (MSCs) in the outer retina mediate pressure responses is unclear. (2) Methods: Immunocytochemistry, patch clamp, and channel fluorescence were used to study MSCs in salamander photoreceptors. (3) Results: Immunoreactivity of transient receptor potential channel vanilloid 4 (TRPV4) was revealed in the outer plexiform layer, K+ channel TRAAK in the photoreceptor outer segment (OS), and TRPV2 in some rod OS disks. Pressure on the rod inner segment evoked sustained currents of three components: (A) the inward current at <-50 mV (Ipi), sensitive to Co2+; (B) leak outward current at ≥-80 mV (Ipo), sensitive to intracellular Cs+ and ruthenium red; and (C) cation current reversed at ~10 mV (Ipc). Hypotonicity induced slow currents like Ipc. Environmental pressure and light increased the FM 1-43-identified open MSCs in the OS membrane, while pressure on the OS with internal Cs+ closed a Ca2+-dependent current reversed at ~0 mV. Rod photocurrents were thermosensitive and affected by MSC blockers. (4) Conclusions: Rods possess depolarizing (TRPV) and hyperpolarizing (K+) MSCs, which mediate mutually compensating currents between -50 mV and 10 mV, serve as an electrical cushion to minimize the impact of ocular mechanical stress.
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Kim HM, Joo K, Han J, Woo SJ. Clinical and Genetic Characteristics of Korean Congenital Stationary Night Blindness Patients. Genes (Basel) 2021; 12:genes12060789. [PMID: 34064005 PMCID: PMC8224030 DOI: 10.3390/genes12060789] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/11/2021] [Accepted: 05/18/2021] [Indexed: 01/27/2023] Open
Abstract
In this study, we investigated the clinical and genetic characteristics of 19 Korean patients with congenital stationary night blindness (CSNB) at two tertiary hospitals. Clinical evaluations, including fundus photography, spectral-domain optical coherence tomography, and electroretinography, were performed. Genetic analyses were conducted using targeted panel sequencing or whole exome sequencing. The median age was 5 (3–21) years at the initial examination, 2 (1–8) years at symptom onset, and 11 (5–28) years during the final visit. Genetic mutations were identified as CNGB1 and GNAT1 for the Riggs type (n = 2), TRPM1 and NYX for the complete type (n = 3), and CACNA1F (n = 14) for the incomplete type. Ten novel variants were identified, and best-corrected visual acuity (BCVA) and spherical equivalents (SE) were related to each type of CSNB. The Riggs and TRPM1 complete types presented mild myopia and good BCVA without strabismus and nystagmus, whereas the NYX complete and incomplete types showed mixed SE and poor BCVA with strabismus and nystagmus. This is the first case series of Korean patients with CSNB, and further studies with a larger number of subjects should be conducted to correlate the clinical and genetic aspects of CSNB.
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Affiliation(s)
- Hyeong-Min Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Korea; (H.-M.K.); (K.J.)
| | - Kwangsic Joo
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Korea; (H.-M.K.); (K.J.)
| | - Jinu Han
- Institute of Vision Research, Department of Ophthalmology, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul 06273, Korea
- Correspondence: (J.H.); (S.-J.W.); Tel.: +82-2-2019-3445 (J.H.); +82-31-787-7377 (S.-J.W.); Fax: +82-2-3463-1049 (J.H.); +82-31-787-4057 (S.-J.W.)
| | - Se-Joon Woo
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam 13620, Korea; (H.-M.K.); (K.J.)
- Correspondence: (J.H.); (S.-J.W.); Tel.: +82-2-2019-3445 (J.H.); +82-31-787-7377 (S.-J.W.); Fax: +82-2-3463-1049 (J.H.); +82-31-787-4057 (S.-J.W.)
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Tang R, Chen W, Wang Y. Different roles of subcortical inputs in V1 responses to luminance and contrast. Eur J Neurosci 2021; 53:3710-3726. [PMID: 33848389 DOI: 10.1111/ejn.15233] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 04/02/2021] [Accepted: 04/09/2021] [Indexed: 01/01/2023]
Abstract
Cells in the primary visual cortex (V1) generally respond weakly to large uniform luminance stimuli. Only a subset of V1 cells is thought to encode uniform luminance information. In natural scenes, local luminance is an important feature for defining an object that varies and coexists with local spatial contrast. However, the strategies used by V1 cells to encode local mean luminance for spatial contrast stimuli remain largely unclear. Here, using extracellular recordings in anesthetized cats, we investigated the responses of V1 cells by comparing with those of retinal ganglion (RG) cells and lateral geniculate nucleus (LGN) cells to simultaneous and rapid changes in luminance and spatial contrast. Almost all V1 cells exhibited a strong monotonic increasing luminance tuning when they were exposed to high spatial contrast. Thus, V1 cells encode the luminance carried by spatial contrast stimuli with the monotonically increasing response function. Moreover, high contrast decreased luminance tuning of OFF cells but increased that of in ON cells in RG and LGN. The luminance and contrast tunings of LGN ON cells were highly separable as V1 cells, whereas those of LGN OFF cells were lowly separable. These asymmetrical effects of spatial contrast on ON/OFF channels might underlie the robust ability of V1 cells to perform luminance tuning when exposed to spatial contrast stimuli.
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Affiliation(s)
- Rendong Tang
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Wenzhen Chen
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yi Wang
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
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Lukasiewcz PD, Bligard GW, DeBrecht JD. EAAT5 Glutamate Transporter-Mediated Inhibition in the Vertebrate Retina. Front Cell Neurosci 2021; 15:662859. [PMID: 34025361 PMCID: PMC8134652 DOI: 10.3389/fncel.2021.662859] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 03/19/2021] [Indexed: 12/29/2022] Open
Abstract
Glutamate transporters typically remove glutamate from the synaptic cleft. In addition, all glutamate transporters have a chloride channel, which is opened upon glutamate binding to the transporter. There are five types of glutamate transporter (EAATs 1–5, excitatory amino acid transporters), which have distinct chloride conductances. Some EAATs that have low chloride conductances, remove glutamate from the synaptic cleft most effectively (e.g., EAAT1). By contrast, EAATs that have high chloride conductances, remove glutamate less effectively (e.g., EAAT5). We have studied EAAT5 in the retina. In the retina, light activates a chloride current, mediated by the glutamate activation of EAAT5. EAAT5 is not a significant contributor to lateral inhibition in the retina. Instead, it is the main source of autoinhibition to rod bipolar cells (RBCs). EAAT5-mediated inhibition has a substantial effect on synaptic transmission from RBCs to downstream retinal neurons.
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Affiliation(s)
- Peter D Lukasiewcz
- Department of Ophthalmology & Visual Sciences, Washington University School of Medicine in St. Louis, St. Louis, MO, United States.,Department of Neuroscience, Washington University School of Medicine in St. Louis, St. Louis, MO, United States
| | - Gregory W Bligard
- Department of Ophthalmology & Visual Sciences, Washington University School of Medicine in St. Louis, St. Louis, MO, United States
| | - James D DeBrecht
- Department of Ophthalmology & Visual Sciences, Washington University School of Medicine in St. Louis, St. Louis, MO, United States
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Orhan E, Neuillé M, de Sousa Dias M, Pugliese T, Michiels C, Condroyer C, Antonio A, Sahel JA, Audo I, Zeitz C. A New Mouse Model for Complete Congenital Stationary Night Blindness Due to Gpr179 Deficiency. Int J Mol Sci 2021; 22:ijms22094424. [PMID: 33922602 PMCID: PMC8122890 DOI: 10.3390/ijms22094424] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 01/24/2023] Open
Abstract
Mutations in GPR179 lead to autosomal recessive complete congenital stationary night blindness (cCSNB). This condition represents a signal transmission defect from the photoreceptors to the ON-bipolar cells. To confirm the phenotype, better understand the pathogenic mechanism in vivo, and provide a model for therapeutic approaches, a Gpr179 knock-out mouse model was genetically and functionally characterized. We confirmed that the insertion of a neo/lac Z cassette in intron 1 of Gpr179 disrupts the same gene. Spectral domain optical coherence tomography reveals no obvious retinal structure abnormalities. Gpr179 knock-out mice exhibit a so-called no-b-wave (nob) phenotype with severely reduced b-wave amplitudes in the electroretinogram. Optomotor tests reveal decreased optomotor responses under scotopic conditions. Consistent with the genetic disruption of Gpr179, GPR179 is absent at the dendritic tips of ON-bipolar cells. While proteins of the same signal transmission cascade (GRM6, LRIT3, and TRPM1) are correctly localized, other proteins (RGS7, RGS11, and GNB5) known to regulate GRM6 are absent at the dendritic tips of ON-bipolar cells. These results add a new model of cCSNB, which is important to better understand the role of GPR179, its implication in patients with cCSNB, and its use for the development of therapies.
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Affiliation(s)
- Elise Orhan
- Institut de la Vision, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Sorbonne Université, F-75012 Paris, France; (E.O.); (M.N.); (M.d.S.D.); (T.P.); (C.M.); (C.C.); (A.A.); (J.-A.S.); (I.A.)
| | - Marion Neuillé
- Institut de la Vision, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Sorbonne Université, F-75012 Paris, France; (E.O.); (M.N.); (M.d.S.D.); (T.P.); (C.M.); (C.C.); (A.A.); (J.-A.S.); (I.A.)
| | - Miguel de Sousa Dias
- Institut de la Vision, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Sorbonne Université, F-75012 Paris, France; (E.O.); (M.N.); (M.d.S.D.); (T.P.); (C.M.); (C.C.); (A.A.); (J.-A.S.); (I.A.)
| | - Thomas Pugliese
- Institut de la Vision, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Sorbonne Université, F-75012 Paris, France; (E.O.); (M.N.); (M.d.S.D.); (T.P.); (C.M.); (C.C.); (A.A.); (J.-A.S.); (I.A.)
| | - Christelle Michiels
- Institut de la Vision, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Sorbonne Université, F-75012 Paris, France; (E.O.); (M.N.); (M.d.S.D.); (T.P.); (C.M.); (C.C.); (A.A.); (J.-A.S.); (I.A.)
| | - Christel Condroyer
- Institut de la Vision, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Sorbonne Université, F-75012 Paris, France; (E.O.); (M.N.); (M.d.S.D.); (T.P.); (C.M.); (C.C.); (A.A.); (J.-A.S.); (I.A.)
| | - Aline Antonio
- Institut de la Vision, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Sorbonne Université, F-75012 Paris, France; (E.O.); (M.N.); (M.d.S.D.); (T.P.); (C.M.); (C.C.); (A.A.); (J.-A.S.); (I.A.)
| | - José-Alain Sahel
- Institut de la Vision, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Sorbonne Université, F-75012 Paris, France; (E.O.); (M.N.); (M.d.S.D.); (T.P.); (C.M.); (C.C.); (A.A.); (J.-A.S.); (I.A.)
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, INSERM-DGOS CIC1423, F-75012 Paris, France
- Fondation Ophtalmologique Adolphe de Rothschild, F-75019 Paris, France
- Academie des Sciences, Institut de France, F-75006 Paris, France
- Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Isabelle Audo
- Institut de la Vision, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Sorbonne Université, F-75012 Paris, France; (E.O.); (M.N.); (M.d.S.D.); (T.P.); (C.M.); (C.C.); (A.A.); (J.-A.S.); (I.A.)
- Centre Hospitalier National d’Ophtalmologie des Quinze-Vingts, INSERM-DGOS CIC1423, F-75012 Paris, France
- Institute of Ophthalmology, University College of London, London EC1V 9EL, UK
| | - Christina Zeitz
- Institut de la Vision, Institut National de la Santé et de la Recherche Médicale, Centre National de la Recherche Scientifique, Sorbonne Université, F-75012 Paris, France; (E.O.); (M.N.); (M.d.S.D.); (T.P.); (C.M.); (C.C.); (A.A.); (J.-A.S.); (I.A.)
- Correspondence: ; Tel.: +33-1-53-46-25-40
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Burger CA, Jiang D, Mackin RD, Samuel MA. Development and maintenance of vision's first synapse. Dev Biol 2021; 476:218-239. [PMID: 33848537 DOI: 10.1016/j.ydbio.2021.04.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/02/2021] [Accepted: 04/03/2021] [Indexed: 12/21/2022]
Abstract
Synapses in the outer retina are the first information relay points in vision. Here, photoreceptors form synapses onto two types of interneurons, bipolar cells and horizontal cells. Because outer retina synapses are particularly large and highly ordered, they have been a useful system for the discovery of mechanisms underlying synapse specificity and maintenance. Understanding these processes is critical to efforts aimed at restoring visual function through repairing or replacing neurons and promoting their connectivity. We review outer retina neuron synapse architecture, neural migration modes, and the cellular and molecular pathways that play key roles in the development and maintenance of these connections. We further discuss how these mechanisms may impact connectivity in the retina.
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Affiliation(s)
- Courtney A Burger
- Huffington Center on Aging, Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Danye Jiang
- Huffington Center on Aging, Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Robert D Mackin
- Huffington Center on Aging, Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA
| | - Melanie A Samuel
- Huffington Center on Aging, Department of Neuroscience, Baylor College of Medicine, Houston, TX, 77030, USA.
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Hori T, Ikuta S, Hattori S, Takao K, Miyakawa T, Koike C. Mice with mutations in Trpm1, a gene in the locus of 15q13.3 microdeletion syndrome, display pronounced hyperactivity and decreased anxiety-like behavior. Mol Brain 2021; 14:61. [PMID: 33785025 PMCID: PMC8008678 DOI: 10.1186/s13041-021-00749-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 02/08/2021] [Indexed: 11/10/2022] Open
Abstract
The 15q13.3 microdeletion syndrome is a genetic disorder characterized by a wide spectrum of psychiatric disorders that is caused by the deletion of a region containing 7 genes on chromosome 15 (MTMR10, FAN1, TRPM1, MIR211, KLF13, OTUD7A, and CHRNA7). The contribution of each gene in this syndrome has been studied using mutant mouse models, but no single mouse model recapitulates the whole spectrum of human 15q13.3 microdeletion syndrome. The behavior of Trpm1-/- mice has not been investigated in relation to 15q13.3 microdeletion syndrome due to the visual impairment in these mice, which may confound the results of behavioral tests involving vision. We were able to perform a comprehensive behavioral test battery using Trpm1 null mutant mice to investigate the role of Trpm1, which is thought to be expressed solely in the retina, in the central nervous system and to examine the relationship between TRPM1 and 15q13.3 microdeletion syndrome. Our data demonstrate that Trpm1-/- mice exhibit abnormal behaviors that may explain some phenotypes of 15q13.3 microdeletion syndrome, including reduced anxiety-like behavior, abnormal social interaction, attenuated fear memory, and the most prominent phenotype of Trpm1 mutant mice, hyperactivity. While the ON visual transduction pathway is impaired in Trpm1-/- mice, we did not detect compensatory high sensitivities for other sensory modalities. The pathway for visual impairment is the same between Trpm1-/- mice and mGluR6-/- mice, but hyperlocomotor activity has not been reported in mGluR6-/- mice. These data suggest that the phenotype of Trpm1-/- mice extends beyond that expected from visual impairment alone. Here, we provide the first evidence associating TRPM1 with impairment of cognitive function similar to that observed in phenotypes of 15q13.3 microdeletion syndrome.
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Affiliation(s)
- Tesshu Hori
- Graduate School of Pharmacy, Ritsumeikan University, Kusatsu, Shiga, Japan
- Laboratory for Systems Neuroscience and Developmental Biology, College of Pharmaceutical Sciences, Ritsumeikan University, Kusatsu, Shiga, Japan
| | - Shohei Ikuta
- Laboratory for Systems Neuroscience and Developmental Biology, College of Pharmaceutical Sciences, Ritsumeikan University, Kusatsu, Shiga, Japan
- Graduate School of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, Japan
| | - Satoko Hattori
- Institute for Comprehensive Medical Science, Fujita Health University, Toyoake, Aichi, Japan
| | - Keizo Takao
- Department of Behavioral Physiology, Faculty of Medicine, University of Toyama, Toyama, Toyama, Japan
- Research Center for Idling Brain Science, University of Toyama, Toyama, Toyama, Japan
- Center for Genetic Analysis of Behavior, National Institute for Physiological Sciences, Okazaki, Aichi, Japan
| | - Tsuyoshi Miyakawa
- Department of Behavioral Physiology, Faculty of Medicine, University of Toyama, Toyama, Toyama, Japan
| | - Chieko Koike
- Graduate School of Pharmacy, Ritsumeikan University, Kusatsu, Shiga, Japan.
- Laboratory for Systems Neuroscience and Developmental Biology, College of Pharmaceutical Sciences, Ritsumeikan University, Kusatsu, Shiga, Japan.
- Center for Systems Vision Science, Research Organization of Science and Technology, Ritsumeikan University, Kusatsu, Shiga, Japan.
- Ritsumeikan Global Innovation Research Organization (R-GIRO), Ritsumeikan University, Kusatsu, Shiga, Japan.
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Meng S, Alanazi R, Ji D, Bandura J, Luo ZW, Fleig A, Feng ZP, Sun HS. Role of TRPM7 kinase in cancer. Cell Calcium 2021; 96:102400. [PMID: 33784560 DOI: 10.1016/j.ceca.2021.102400] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 03/18/2021] [Accepted: 03/20/2021] [Indexed: 01/09/2023]
Abstract
Cancer is the second leading cause of death worldwide and accounted for an estimated 9.6 million deaths, or 1 in 6 deaths, in 2018. Despite recent advances in cancer prevention, diagnosis, and treatment strategies, the burden of this disease continues to grow with each year, with dire physical, emotional, and economic consequences for all levels of society. Classic characteristics of cancer include rapid, uncontrolled cell proliferation and spread of cancerous cells to other parts of the body, a process known as metastasis. Transient receptor potential melastatin 7 (TRPM7), a Ca2+- and Mg2+-permeable nonselective divalent cation channel defined by the atypical presence of an α-kinase within its C-terminal domain, has been implicated, due to its modulation of Ca2+ and Mg2+ influx, in a wide variety of physiological and pathological processes, including cancer. TRPM7 is overexpressed in several cancer types and has been shown to variably increase cellular proliferation, migration, and invasion of tumour cells. However, the relative contribution of TRPM7 kinase domain activity to cancer as opposed to ion flux through its channel pore remains an area of active discovery. In this review, we describe the specific role of the TRPM7 kinase domain in cancer processes as well as mechanisms of regulation and inhibition of the kinase domain.
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Affiliation(s)
- Selena Meng
- Department of Surgery, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada; Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada
| | - Rahmah Alanazi
- Department of Surgery, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada; Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada
| | - Delphine Ji
- Department of Surgery, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada; Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada
| | - Julia Bandura
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada
| | - Zheng-Wei Luo
- Department of Surgery, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada; Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada
| | - Andrea Fleig
- Center for Biomedical Research at The Queen's Medical Center and John A. Burns School of Medicine and Cancer Center at the University of Hawaii, Honolulu, HI, 96720, USA
| | - Zhong-Ping Feng
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada.
| | - Hong-Shuo Sun
- Department of Surgery, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada; Department of Physiology, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada; Department of Pharmacology, Temerty Faculty of Medicine, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada; Leslie Dan Faculty of Pharmacy, University of Toronto, 1 King's College Circle, Toronto, Ontario, Canada.
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Babai N, Wittgenstein J, Gierke K, Brandstätter JH, Feigenspan A. The absence of functional bassoon at cone photoreceptor ribbon synapses affects signal transmission at Off cone bipolar cell contacts in mouse retina. Acta Physiol (Oxf) 2021; 231:e13584. [PMID: 33222426 DOI: 10.1111/apha.13584] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 10/21/2020] [Accepted: 11/19/2020] [Indexed: 01/05/2023]
Abstract
AIM Off cone bipolar cells of the mammalian retina connect to cone photoreceptor synaptic terminals via non-invaginating flat contacts at a considerable distance from the only established neurotransmitter release site so far, the synaptic ribbon. Diffusion from the ribbon synaptic active zone is considered the most likely mechanism for the neurotransmitter glutamate to reach postsynaptic receptors on the dendritic tips of Off cone bipolar cells. We used a mutant mouse with functionally impaired photoreceptor ribbon synapses to investigate the importance of intact ribbon synaptic active zones for signal transmission at Off cone bipolar cell contacts. METHODS Whole-cell patch-clamp recordings from Off cone bipolar cells in a horizontal slice preparation of wildtype (Bsnwt ) and mutant (BsnΔEx4/5 ) mouse retina were applied to investigate signal transmission between cone photoreceptors and Off cone bipolar cells. The distribution of postsynaptic glutamate receptors in Off cone bipolar cell dendrites was studied using multiplex immunocytochemistry. RESULTS Tonic synaptic activity and evoked release were significantly reduced in mutant animals. Vesicle replenishment rates and the size of the readily releasable pool were likewise decreased. The precisely timed transient current response to light offset changed to a sustained response in the mutant, exemplified by random release events only loosely time-locked to the stimulus. The kainate receptor distribution in postsynaptic Off cone bipolar cell dendritic contacts in BsnΔEx4/5 mice was largely disturbed. CONCLUSION Our results suggest a major role of functional ribbon synaptic active zones for signal transmission and postsynaptic glutamate receptor organization at flat Off cone bipolar cell contacts.
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Affiliation(s)
- Norbert Babai
- Department of Biology, Animal Physiology FAU Erlangen‐Nürnberg Erlangen Germany
| | - Julia Wittgenstein
- Department of Biology, Animal Physiology FAU Erlangen‐Nürnberg Erlangen Germany
| | - Kaspar Gierke
- Department of Biology, Animal Physiology FAU Erlangen‐Nürnberg Erlangen Germany
| | | | - Andreas Feigenspan
- Department of Biology, Animal Physiology FAU Erlangen‐Nürnberg Erlangen Germany
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Gregory KJ, Goudet C. International Union of Basic and Clinical Pharmacology. CXI. Pharmacology, Signaling, and Physiology of Metabotropic Glutamate Receptors. Pharmacol Rev 2020; 73:521-569. [PMID: 33361406 DOI: 10.1124/pr.119.019133] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Metabotropic glutamate (mGlu) receptors respond to glutamate, the major excitatory neurotransmitter in the mammalian brain, mediating a modulatory role that is critical for higher-order brain functions such as learning and memory. Since the first mGlu receptor was cloned in 1992, eight subtypes have been identified along with many isoforms and splice variants. The mGlu receptors are transmembrane-spanning proteins belonging to the class C G protein-coupled receptor family and represent attractive targets for a multitude of central nervous system disorders. Concerted drug discovery efforts over the past three decades have yielded a wealth of pharmacological tools including subtype-selective agents that competitively block or mimic the actions of glutamate or act allosterically via distinct sites to enhance or inhibit receptor activity. Herein, we review the physiologic and pathophysiological roles for individual mGlu receptor subtypes including the pleiotropic nature of intracellular signal transduction arising from each. We provide a comprehensive analysis of the in vitro and in vivo pharmacological properties of prototypical and commercially available orthosteric agonists and antagonists as well as allosteric modulators, including ligands that have entered clinical trials. Finally, we highlight emerging areas of research that hold promise to facilitate rational design of highly selective mGlu receptor-targeting therapeutics in the future. SIGNIFICANCE STATEMENT: The metabotropic glutamate receptors are attractive therapeutic targets for a range of psychiatric and neurological disorders. Over the past three decades, intense discovery efforts have yielded diverse pharmacological tools acting either competitively or allosterically, which have enabled dissection of fundamental biological process modulated by metabotropic glutamate receptors and established proof of concept for many therapeutic indications. We review metabotropic glutamate receptor molecular pharmacology and highlight emerging areas that are offering new avenues to selectively modulate neurotransmission.
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Affiliation(s)
- Karen J Gregory
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (K.J.G.) and Institut de Génomique Fonctionnelle (IGF), University of Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de la Sante et de la Recherche Medicale (INSERM), Montpellier, France (C.G.)
| | - Cyril Goudet
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences and Department of Pharmacology, Monash University, Parkville, Victoria, Australia (K.J.G.) and Institut de Génomique Fonctionnelle (IGF), University of Montpellier, Centre National de la Recherche Scientifique (CNRS), Institut National de la Sante et de la Recherche Medicale (INSERM), Montpellier, France (C.G.)
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Jimenez I, Prado Y, Marchant F, Otero C, Eltit F, Cabello-Verrugio C, Cerda O, Simon F. TRPM Channels in Human Diseases. Cells 2020; 9:E2604. [PMID: 33291725 PMCID: PMC7761947 DOI: 10.3390/cells9122604] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 11/30/2020] [Accepted: 12/01/2020] [Indexed: 12/11/2022] Open
Abstract
The transient receptor potential melastatin (TRPM) subfamily belongs to the TRP cation channels family. Since the first cloning of TRPM1 in 1989, tremendous progress has been made in identifying novel members of the TRPM subfamily and their functions. The TRPM subfamily is composed of eight members consisting of four six-transmembrane domain subunits, resulting in homomeric or heteromeric channels. From a structural point of view, based on the homology sequence of the coiled-coil in the C-terminus, the eight TRPM members are clustered into four groups: TRPM1/M3, M2/M8, M4/M5 and M6/M7. TRPM subfamily members have been involved in several physiological functions. However, they are also linked to diverse pathophysiological human processes. Alterations in the expression and function of TRPM subfamily ion channels might generate several human diseases including cardiovascular and neurodegenerative alterations, organ dysfunction, cancer and many other channelopathies. These effects position them as remarkable putative targets for novel diagnostic strategies, drug design and therapeutic approaches. Here, we review the current knowledge about the main characteristics of all members of the TRPM family, focusing on their actions in human diseases.
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Affiliation(s)
- Ivanka Jimenez
- Faculty of Life Science, Universidad Andrés Bello, Santiago 8370186, Chile; (I.J.); (Y.P.); (F.M.); (C.C.-V.)
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Chile, Santiago 8380453, Chile;
| | - Yolanda Prado
- Faculty of Life Science, Universidad Andrés Bello, Santiago 8370186, Chile; (I.J.); (Y.P.); (F.M.); (C.C.-V.)
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Chile, Santiago 8380453, Chile;
| | - Felipe Marchant
- Faculty of Life Science, Universidad Andrés Bello, Santiago 8370186, Chile; (I.J.); (Y.P.); (F.M.); (C.C.-V.)
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Chile, Santiago 8380453, Chile;
| | - Carolina Otero
- Faculty of Medicine, School of Chemistry and Pharmacy, Universidad Andrés Bello, Santiago 8370186, Chile;
| | - Felipe Eltit
- Vancouver Prostate Centre, Vancouver, BC V6Z 1Y6, Canada;
- Department of Urological Sciences, University of British Columbia, Vancouver, BC V6Z 1Y6, Canada
| | - Claudio Cabello-Verrugio
- Faculty of Life Science, Universidad Andrés Bello, Santiago 8370186, Chile; (I.J.); (Y.P.); (F.M.); (C.C.-V.)
- Center for the Development of Nanoscience and Nanotechnology (CEDENNA), Universidad de Santiago de Chile, Santiago 7560484, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago 8370146, Chile
| | - Oscar Cerda
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Chile, Santiago 8380453, Chile;
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences (ICBM), Faculty of Medicine, Universidad de Chile, Santiago 8380453, Chile
| | - Felipe Simon
- Faculty of Life Science, Universidad Andrés Bello, Santiago 8370186, Chile; (I.J.); (Y.P.); (F.M.); (C.C.-V.)
- Millennium Nucleus of Ion Channel-Associated Diseases (MiNICAD), Universidad de Chile, Santiago 8380453, Chile;
- Millennium Institute on Immunology and Immunotherapy, Santiago 8370146, Chile
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Palazzo E, Boccella S, Marabese I, Pierretti G, Guida F, Maione S. The Cold Case of Metabotropic Glutamate Receptor 6: Unjust Detention in the Retina? Curr Neuropharmacol 2020; 18:120-125. [PMID: 31573889 PMCID: PMC7324884 DOI: 10.2174/1570159x17666191001141849] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 08/20/2019] [Accepted: 09/29/2019] [Indexed: 02/03/2023] Open
Abstract
It is a common opinion that metabotropic glutamate receptor subtype 6 (mGluR6) is expressed exclusively in the retina, and in particular in the dendrites of ON-bipolar cells. Glutamate released in darkness from photoreceptors activates mGluR6, which is negatively associated with a membrane non-selective cation channel, the transient receptor potential melanoma-related 1, TRPM1, resulting in cell hyperpolarization. The evidence that mGluR6 is expressed not only in the retina but also in other tissues and cell populations has accumulated over time. The expression of mGluR6 has been identified in microglia, bone marrow stromal and prostate cancer cells, B lymphocytes, melanocytes and keratinocytes and non-neural tissues such as testis, kidney, cornea, conjunctiva, and eyelid. The receptor also appears to be expressed in brain areas, such as the hypothalamus, cortex, hippocampus, nucleus of tractus solitarius, superior colliculus, axons of the corpus callosum and accessory olfactory bulb. The pharmacological activation of mGluR6 in the hippocampus produced an anxiolytic-like effect and in the periaqueductal gray analgesic potential. This review aims to collect all the evidence on the expression and functioning of mGluR6 outside the retina that has been accumulated over the years for a broader view of the potential of the receptor whose retinal confinement appears understimated.
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Affiliation(s)
- E Palazzo
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Naples, Italy
| | - S Boccella
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Naples, Italy
| | - I Marabese
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Naples, Italy
| | - G Pierretti
- Department of Plastic Surgery, University of Campania "L. Vanvitelli", Naples, Italy
| | - F Guida
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Naples, Italy
| | - S Maione
- Department of Experimental Medicine, Pharmacology Division, University of Campania "L. Vanvitelli", Naples, Italy
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Rai D, Akagi T, Shimohata A, Ishii T, Gangi M, Maruyama T, Wada-Kiyama Y, Ogiwara I, Kaneda M. Involvement of the C-terminal domain in cell surface localization and G-protein coupling of mGluR6. J Neurochem 2020; 158:837-848. [PMID: 33067823 DOI: 10.1111/jnc.15217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Revised: 05/25/2020] [Accepted: 10/11/2020] [Indexed: 01/05/2023]
Abstract
Metabotropic glutamate receptor 6, mGluR6, interacts with scaffold proteins and Gβγ subunits via its intracellular C-terminal domain (CTD). The mGluR6 pathway is critically involved in the retinal processing of visual signals. We herein investigated whether the CTD (residues 840-871) was necessary for mGluR6 cell surface localization and G-protein coupling using mGluR6-CTD mutants with immunocytochemistry, surface biotinylation assays, and electrophysiological approaches. We used 293T cells and primary hippocampal neurons as model systems. We examined C-terminally truncated mGluR6 and showed that the removal of up to residue 858 did not affect surface localization or glutamate-induced G-protein-mediated responses, whereas a 15-amino acid deletion (Δ857-871) impaired these functions. However, a 21-amino acid deletion (Δ851-871) restored surface localization and glutamate-dependent responses, which were again attenuated when the entire CTD was removed. The sequence alignment of group III mGluRs showed conserved amino acids resembling an ER retention motif in the CTD. These results suggest that the intracellular CTD is required for the cell surface transportation and receptor function of mGluR6, whereas it may contain regulatory elements for intracellular trafficking and signaling.
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Affiliation(s)
- Dilip Rai
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | - Takumi Akagi
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | | | - Toshiyuki Ishii
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | - Mie Gangi
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | - Takuma Maruyama
- Department of Physiology, Nippon Medical School, Tokyo, Japan
| | | | - Ikuo Ogiwara
- Department of Physiology, Nippon Medical School, Tokyo, Japan
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Ma C, Li X, Chen J, Li Z, Guan J, Li Y, Yin S, Shi Y. Association Analysis Between Common Variants of the TRPM1 Gene and Three Mental Disorders in the Han Chinese Population. Genet Test Mol Biomarkers 2020; 24:649-657. [PMID: 33001715 PMCID: PMC7585623 DOI: 10.1089/gtmb.2019.0096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Objective: Our study was designed to determine if the TRPM1 gene is associated with any of three mental disorders. The project included a cross disorder meta-analysis and association analysis including 141701 cases and 175248 controls. Materials and Methods: We genotyped eight tag single nucleotide polymorphisms (SNPs) in 1248 unrelated schizophrenia (SCZ) patients, 1056 major depressive disorder patients, 1344 bipolar disorder patients, and 1248 normal controls. We then performed a meta-analysis of 10 GWASs to identify common genetic factors among these three mental disorders. Finally, we performed a meta-analysis of six GWASs to explore the role of rs10162727 in SCZ. Result: Although two haplotypes of the TRPM1 gene, rs1035706-rs10162727 and rs10162727-rs3784599, were identified in the control group, as well as all three disease groups, none of the eight tag SNP associations remained significant after correction for multiple tests. In this cross-disorder meta-analysis of the three diseases, none of the tag SNPs were confirmed to be common among the diseases. In addition, in the meta-analysis conducted for the rs10162727 locus in SCZ, there was no significant association (p-value = 0.84, odds ratio = 1.02 [95% CI = 0.87-1.19]). Conclusion: In the Han Chinese population, no significant evidence was found linking variants of the TRPM1 gene with any of the mental disorders examined.
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Affiliation(s)
- Chuanchuan Ma
- Department of Biology, School of Life Science, Anhui Medical University, Hefei, China
| | - Xiuli Li
- Department of Biology, School of Life Science, Anhui Medical University, Hefei, China
| | - Jianhua Chen
- Department of Biology, School of Life Science, Anhui Medical University, Hefei, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Department of Otolaryngology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Department of Otolaryngology, Therapy Center for Obstructive Sleep Apnea, Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
| | - Zhiqiang Li
- Department of Biology, School of Life Science, Anhui Medical University, Hefei, China
- Department of Otolaryngology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Department of Otolaryngology, Therapy Center for Obstructive Sleep Apnea, Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
- The Affiliated Hospital of Qingdao University, The Biomedical Sciences Institute of Qingdao University (Qingdao Branch of SJTU Bio-X Institutes), Qingdao University, Qingdao, People's Republic of China
| | - Jian Guan
- Department of Otolaryngology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Department of Otolaryngology, Therapy Center for Obstructive Sleep Apnea, Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
| | - Yigang Li
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Department of Cardiology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education) and the Collaborative Innovation Center for Brain Science, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Shankai Yin
- Department of Otolaryngology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Department of Otolaryngology, Therapy Center for Obstructive Sleep Apnea, Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
| | - Yongyong Shi
- Department of Biology, School of Life Science, Anhui Medical University, Hefei, China
- Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Department of Otolaryngology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Department of Otolaryngology, Therapy Center for Obstructive Sleep Apnea, Otolaryngology Institute of Shanghai Jiao Tong University, Shanghai, China
- The Affiliated Hospital of Qingdao University, The Biomedical Sciences Institute of Qingdao University (Qingdao Branch of SJTU Bio-X Institutes), Qingdao University, Qingdao, People's Republic of China
- Department of Cardiology, Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education) and the Collaborative Innovation Center for Brain Science, Shanghai Jiao Tong University, Shanghai, People's Republic of China
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Sensing through Non-Sensing Ocular Ion Channels. Int J Mol Sci 2020; 21:ijms21186925. [PMID: 32967234 PMCID: PMC7554890 DOI: 10.3390/ijms21186925] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/12/2022] Open
Abstract
Ion channels are membrane-spanning integral proteins expressed in multiple organs, including the eye. In the eye, ion channels are involved in various physiological processes, like signal transmission and visual processing. A wide range of mutations have been reported in the corresponding genes and their interacting subunit coding genes, which contribute significantly to an array of blindness, termed ocular channelopathies. These mutations result in either a loss- or gain-of channel functions affecting the structure, assembly, trafficking, and localization of channel proteins. A dominant-negative effect is caused in a few channels formed by the assembly of several subunits that exist as homo- or heteromeric proteins. Here, we review the role of different mutations in switching a “sensing” ion channel to “non-sensing,” leading to ocular channelopathies like Leber’s congenital amaurosis 16 (LCA16), cone dystrophy, congenital stationary night blindness (CSNB), achromatopsia, bestrophinopathies, retinitis pigmentosa, etc. We also discuss the various in vitro and in vivo disease models available to investigate the impact of mutations on channel properties, to dissect the disease mechanism, and understand the pathophysiology. Innovating the potential pharmacological and therapeutic approaches and their efficient delivery to the eye for reversing a “non-sensing” channel to “sensing” would be life-changing.
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Maddox JW, Randall KL, Yadav RP, Williams B, Hagen J, Derr PJ, Kerov V, Della Santina L, Baker SA, Artemyev N, Hoon M, Lee A. A dual role for Ca v1.4 Ca 2+ channels in the molecular and structural organization of the rod photoreceptor synapse. eLife 2020; 9:e62184. [PMID: 32940604 PMCID: PMC7561352 DOI: 10.7554/elife.62184] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 09/09/2020] [Indexed: 02/06/2023] Open
Abstract
Synapses are fundamental information processing units that rely on voltage-gated Ca2+ (Cav) channels to trigger Ca2+-dependent neurotransmitter release. Cav channels also play Ca2+-independent roles in other biological contexts, but whether they do so in axon terminals is unknown. Here, we addressed this unknown with respect to the requirement for Cav1.4 L-type channels for the formation of rod photoreceptor synapses in the retina. Using a mouse strain expressing a non-conducting mutant form of Cav1.4, we report that the Cav1.4 protein, but not its Ca2+ conductance, is required for the molecular assembly of rod synapses; however, Cav1.4 Ca2+ signals are needed for the appropriate recruitment of postsynaptic partners. Our results support a model in which presynaptic Cav channels serve both as organizers of synaptic building blocks and as sources of Ca2+ ions in building the first synapse of the visual pathway and perhaps more broadly in the nervous system.
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Affiliation(s)
- J Wesley Maddox
- Department of Molecular Physiology and Biophysics, University of IowaIowa CityUnited States
- Iowa Neuroscience Institute, University of IowaIowa CityUnited States
- Pappajohn Biomedical Institute, University of IowaIowa CityUnited States
| | - Kate L Randall
- Department of Molecular Physiology and Biophysics, University of IowaIowa CityUnited States
- Iowa Neuroscience Institute, University of IowaIowa CityUnited States
- Pappajohn Biomedical Institute, University of IowaIowa CityUnited States
| | - Ravi P Yadav
- Department of Molecular Physiology and Biophysics, University of IowaIowa CityUnited States
| | - Brittany Williams
- Department of Molecular Physiology and Biophysics, University of IowaIowa CityUnited States
- Iowa Neuroscience Institute, University of IowaIowa CityUnited States
- Pappajohn Biomedical Institute, University of IowaIowa CityUnited States
| | - Jussara Hagen
- Department of Molecular Physiology and Biophysics, University of IowaIowa CityUnited States
- Iowa Neuroscience Institute, University of IowaIowa CityUnited States
- Pappajohn Biomedical Institute, University of IowaIowa CityUnited States
| | - Paul J Derr
- Department of Neuroscience, University of Wisconsin-MadisonMadisonUnited States
| | - Vasily Kerov
- Department of Molecular Physiology and Biophysics, University of IowaIowa CityUnited States
- Iowa Neuroscience Institute, University of IowaIowa CityUnited States
| | - Luca Della Santina
- Department of Ophthalmology, University of California, San FranciscoSan FranciscoUnited States
| | - Sheila A Baker
- Iowa Neuroscience Institute, University of IowaIowa CityUnited States
- Department of Biochemistry, University of IowaIowa CityUnited States
- Department of OphthalmologyIowa CityUnited States
| | - Nikolai Artemyev
- Department of Molecular Physiology and Biophysics, University of IowaIowa CityUnited States
- Iowa Neuroscience Institute, University of IowaIowa CityUnited States
- Department of OphthalmologyIowa CityUnited States
| | - Mrinalini Hoon
- Department of Neuroscience, University of Wisconsin-MadisonMadisonUnited States
- Department of Ophthalmology and Visual Science, University of Wisconsin-MadisonMadisonUnited States
| | - Amy Lee
- Department of Molecular Physiology and Biophysics, University of IowaIowa CityUnited States
- Iowa Neuroscience Institute, University of IowaIowa CityUnited States
- Pappajohn Biomedical Institute, University of IowaIowa CityUnited States
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CLINICAL COURSE OF PARANEOPLASTIC RETINOPATHY WITH ANTI-TRPM1 AUTOANTIBODY IN JAPANESE COHORT. Retina 2020; 39:2410-2418. [PMID: 30260920 DOI: 10.1097/iae.0000000000002329] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE To report the clinical course of eyes with paraneoplastic retinopathy caused by an autoantibody against transient receptor potential cation channel, subfamily M, member 1 (TRPM1). METHODS Ten paraneoplastic retinopathy patients with retinal ON-bipolar cell dysfunction, including six melanoma-associated retinopathy, from eight institutions in Japan were evaluated for the presence of an anti-TRPM1 antibody. The results of ophthalmic examinations and the presence of anti-TRPM1 antibody were analyzed. RESULTS Five patients were positive for the anti-TRPM1 antibody. These patients had similar clinical findings in both eyes at the time of diagnosis; relatively preserved best-corrected visual acuity, absence of fundus and optical coherence tomography abnormalities, and specific abnormalities of the electroretinography (ERG); and negative-type ERGs with bright stimulus flashes. One patient whose retinal ON-bipolar cells remained dysfunctional for the entire testing period, although the anti-TRPM1 antibody had disappeared. On the other hand, the ERGs recovered in 2 cases within 2 years after the onset. One case progressed to additional impairment of the photoreceptors with deterioration of ERGs. One case died and the clinical course was unavailable. CONCLUSION Paraneoplastic retinopathy patients with retinal ON-bipolar cell dysfunction possess autoantibodies against TRPM1 at the onset of the disease process; however, the clinical course of these eyes can be different.
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