1
|
Miller AL, Fuller-Carter PI, Masarini K, Samardzija M, Carter KW, Rashwan R, Lim XR, Brunet AA, Chopra A, Ram R, Grimm C, Ueffing M, Carvalho LS, Trifunović D. Increased H3K27 trimethylation contributes to cone survival in a mouse model of cone dystrophy. Cell Mol Life Sci 2022; 79:409. [PMID: 35810394 PMCID: PMC9271452 DOI: 10.1007/s00018-022-04436-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 06/16/2022] [Accepted: 06/17/2022] [Indexed: 11/30/2022]
Abstract
Inherited retinal diseases (IRDs) are a heterogeneous group of blinding disorders, which result in dysfunction or death of the light-sensing cone and rod photoreceptors. Despite individual IRDs (Inherited retinal disease) being rare, collectively, they affect up to 1:2000 people worldwide, causing a significant socioeconomic burden, especially when cone-mediated central vision is affected. This study uses the Pde6ccpfl1 mouse model of achromatopsia, a cone-specific vision loss IRD (Inherited retinal disease), to investigate the potential gene-independent therapeutic benefits of a histone demethylase inhibitor GSK-J4 on cone cell survival. We investigated the effects of GSK-J4 treatment on cone cell survival in vivo and ex vivo and changes in cone-specific gene expression via single-cell RNA sequencing. A single intravitreal GSK-J4 injection led to transcriptional changes in pathways involved in mitochondrial dysfunction, endoplasmic reticulum stress, among other key epigenetic pathways, highlighting the complex interplay between methylation and acetylation in healthy and diseased cones. Furthermore, continuous administration of GSK-J4 in retinal explants increased cone survival. Our results suggest that IRD (Inherited retinal disease)-affected cones respond positively to epigenetic modulation of histones, indicating the potential of this approach in developing a broad class of novel therapies to slow cone degeneration.
Collapse
Affiliation(s)
- Annie L Miller
- Retinal Genomics and Therapy Group, Lions Eye Institute Ltd, 2 Verdun Street, Nedlands, WA, 6009, Australia
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Hwy, Crawley, WA, 6009, Australia
| | - Paula I Fuller-Carter
- Retinal Genomics and Therapy Group, Lions Eye Institute Ltd, 2 Verdun Street, Nedlands, WA, 6009, Australia
| | - Klaudija Masarini
- Institute for Ophthalmic Research, Tübingen University, Elfriede-Aulhorn-Straße 7, 72076, Tübingen, Germany
| | - Marijana Samardzija
- Lab for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zürich, University of Zürich, Zurich, Switzerland
| | - Kim W Carter
- Analytical Computing Solutions, Willetton, WA, 6155, Australia
| | - Rabab Rashwan
- Retinal Genomics and Therapy Group, Lions Eye Institute Ltd, 2 Verdun Street, Nedlands, WA, 6009, Australia
- Department of Microbiology and Immunology, Faculty of Medicine, Minia University, Minia, Egypt
| | - Xin Ru Lim
- Retinal Genomics and Therapy Group, Lions Eye Institute Ltd, 2 Verdun Street, Nedlands, WA, 6009, Australia
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Hwy, Crawley, WA, 6009, Australia
| | - Alicia A Brunet
- Retinal Genomics and Therapy Group, Lions Eye Institute Ltd, 2 Verdun Street, Nedlands, WA, 6009, Australia
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Hwy, Crawley, WA, 6009, Australia
| | - Abha Chopra
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, WA, Australia
- Department of Medicine, Vanderbilt University Medical Centre, Nashville, TN, USA
| | - Ramesh Ram
- Institute for Immunology and Infectious Diseases, Murdoch University, Murdoch, WA, Australia
| | - Christian Grimm
- Lab for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zürich, University of Zürich, Zurich, Switzerland
| | - Marius Ueffing
- Institute for Ophthalmic Research, Tübingen University, Elfriede-Aulhorn-Straße 7, 72076, Tübingen, Germany
| | - Livia S Carvalho
- Retinal Genomics and Therapy Group, Lions Eye Institute Ltd, 2 Verdun Street, Nedlands, WA, 6009, Australia.
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 35 Stirling Hwy, Crawley, WA, 6009, Australia.
| | - Dragana Trifunović
- Institute for Ophthalmic Research, Tübingen University, Elfriede-Aulhorn-Straße 7, 72076, Tübingen, Germany.
| |
Collapse
|
2
|
Alcami P, Totagera S, Sohnius-Wilhelmi N, Leitner S, Grothe B, Frankl-Vilches C, Gahr M. Extensive GJD2 Expression in the Song Motor Pathway Reveals the Extent of Electrical Synapses in the Songbird Brain. BIOLOGY 2021; 10:biology10111099. [PMID: 34827092 PMCID: PMC8615078 DOI: 10.3390/biology10111099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Revised: 10/06/2021] [Accepted: 10/14/2021] [Indexed: 06/13/2023]
Abstract
Birdsong is a precisely timed animal behavior. The connectivity of song premotor neural networks has been proposed to underlie the temporal patterns of neuronal activity that control vocal muscle movements during singing. Although the connectivity of premotor nuclei via chemical synapses has been characterized, electrical synapses and their molecular identity remain unexplored. We show with in situ hybridizations that GJD2 mRNA, coding for the major channel-forming electrical synapse protein in mammals, connexin 36, is expressed in the two nuclei that control song production, HVC and RA from canaries and zebra finches. In canaries' HVC, GJD2 mRNA is extensively expressed in GABAergic and only a fraction of glutamatergic cells. By contrast, in RA, GJD2 mRNA expression is widespread in glutamatergic and GABAergic neurons. Remarkably, GJD2 expression is similar in song nuclei and their respective embedding brain regions, revealing the widespread expression of GJD2 in the avian brain. Inspection of a single-cell sequencing database from zebra and Bengalese finches generalizes the distributions of electrical synapses across cell types and song nuclei that we found in HVC and RA from canaries, reveals a differential GJD2 mRNA expression in HVC glutamatergic subtypes and its transient increase along the neurogenic lineage. We propose that songbirds are a suitable model to investigate the contribution of electrical synapses to motor skill learning and production.
Collapse
Affiliation(s)
- Pepe Alcami
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße, 82319 Starnberg, Germany; (S.T.); (N.S.-W.); (S.L.); (C.F.-V.); (M.G.)
- Division of Neurobiology, Faculty of Biology, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, D-82152 Planegg-Martinsried, Germany;
| | - Santhosh Totagera
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße, 82319 Starnberg, Germany; (S.T.); (N.S.-W.); (S.L.); (C.F.-V.); (M.G.)
- Division of Neurobiology, Faculty of Biology, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, D-82152 Planegg-Martinsried, Germany;
| | - Nina Sohnius-Wilhelmi
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße, 82319 Starnberg, Germany; (S.T.); (N.S.-W.); (S.L.); (C.F.-V.); (M.G.)
| | - Stefan Leitner
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße, 82319 Starnberg, Germany; (S.T.); (N.S.-W.); (S.L.); (C.F.-V.); (M.G.)
| | - Benedikt Grothe
- Division of Neurobiology, Faculty of Biology, Ludwig-Maximilians-Universität München, Grosshaderner Strasse 2, D-82152 Planegg-Martinsried, Germany;
| | - Carolina Frankl-Vilches
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße, 82319 Starnberg, Germany; (S.T.); (N.S.-W.); (S.L.); (C.F.-V.); (M.G.)
| | - Manfred Gahr
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße, 82319 Starnberg, Germany; (S.T.); (N.S.-W.); (S.L.); (C.F.-V.); (M.G.)
| |
Collapse
|
3
|
Günther A, Dedek K, Haverkamp S, Irsen S, Briggman KL, Mouritsen H. Double Cones and the Diverse Connectivity of Photoreceptors and Bipolar Cells in an Avian Retina. J Neurosci 2021; 41:5015-5028. [PMID: 33893221 PMCID: PMC8197639 DOI: 10.1523/jneurosci.2495-20.2021] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 03/03/2021] [Accepted: 04/01/2021] [Indexed: 12/24/2022] Open
Abstract
Double cones are the most common photoreceptor cell type in most avian retinas, but their precise functions remain a mystery. Among their suggested functions are luminance detection, polarized light detection, and light-dependent, radical pair-based magnetoreception. To better understand the function of double cones, it will be crucial to know how they are connected to the neural network in the avian retina. Here we use serial sectioning, multibeam scanning electron microscopy to investigate double-cone anatomy and connectivity with a particular focus on their contacts to other photoreceptor and bipolar cells in the chicken retina. We found that double cones are highly connected to neighboring double cones and with other photoreceptor cells through telodendria-to-terminal and telodendria-to-telodendria contacts. We also identified 15 bipolar cell types based on their axonal stratifications, photoreceptor contact pattern, soma position, and dendritic and axonal field mosaics. Thirteen of these 15 bipolar cell types contacted at least one or both members of the double cone. All bipolar cells were bistratified or multistratified. We also identified surprising contacts between other cone types and between rods and cones. Our data indicate a much more complex connectivity network in the outer plexiform layer of the avian retina than originally expected.SIGNIFICANCE STATEMENT Like in humans, vision is one of the most important senses for birds. Here, we present the first serial section multibeam scanning electron microscopy dataset from any bird retina. We identified many previously undescribed rod-to-cone and cone-to-cone connections. Surprisingly, of the 15 bipolar cell types we identified, 11 received input from rods and 13 of 15 received at least part of their input from double cones. Therefore, double cones seem to play many different and important roles in avian retinal processing, and the neural network and thus information processing in the outer retina are much more complex than previously expected. These fundamental findings will be very important for several fields of science, including vertebrate vision, avian magnetoreception, and comparative neuroanatomy.
Collapse
Affiliation(s)
- Anja Günther
- Neurosensorics/Animal Navigation, Institute for Biology and Environmental Sciences, Carl von Ossietzky University of Oldenburg, 26129 Oldenburg, Germany
| | - Karin Dedek
- Neurosensorics/Animal Navigation, Institute for Biology and Environmental Sciences, Carl von Ossietzky University of Oldenburg, 26129 Oldenburg, Germany
- Research Center for Neurosensory Sciences, Carl von Ossietzky University of Oldenburg, 26129 Oldenburg, Germany
| | - Silke Haverkamp
- Department of Computational Neuroethology, Center of Advanced European Studies and Reasearch (caesar), 53175 Bonn, Germany
| | - Stephan Irsen
- Electron Microscopy and Analytics, Center of Advanced European Studies and Research (caesar), 53175 Bonn, Germany
| | - Kevin L Briggman
- Department of Computational Neuroethology, Center of Advanced European Studies and Reasearch (caesar), 53175 Bonn, Germany
| | - Henrik Mouritsen
- Neurosensorics/Animal Navigation, Institute for Biology and Environmental Sciences, Carl von Ossietzky University of Oldenburg, 26129 Oldenburg, Germany
- Research Center for Neurosensory Sciences, Carl von Ossietzky University of Oldenburg, 26129 Oldenburg, Germany
| |
Collapse
|
4
|
Abstract
Our previous research showed that increased phosphorylation of connexin (Cx)36 indicated extended coupling of AII amacrine cells (ACs) in the rod-dominant mouse myopic retina. This research will determine whether phosphorylation at serine 276 of Cx35-containing gap junctions increased in the myopic chicken, whose retina is cone-dominant. Refractive errors and ocular biometric dimensions of 7-days-old chickens were determined following 12 h and 7 days induction of myopia by a −10D lens. The expression pattern and size of Cx35-positive plaques were examined in the early (12 h) and compensated stages (7 days) of lens-induced myopia (LIM). At the same time, phosphorylation at serine 276 (functional assay) of Cx35 in strata 5 (S5) of the inner plexiform layer was investigated. The axial length of the 7 days LIM eyes was significantly longer than that of non-LIM controls (P < 0.05). Anti-phospho-Ser276 (Ser276-P)-labeled plaques were significantly increased in LIM retinas at both 12 h and 7 days. The density of Ser276-P of Cx35 was observed to increase after 12 h LIM. In the meanwhile, the areas of existing Cx35 plaques did not change. As there was more phosphorylation of connexin35 at Ser276 at both the early and late stages (12 h) and 7 days of LIM chicken retinal activity, the coupling with ACs could be increased in myopia development of the cone-dominated chicken retina.
Collapse
|
5
|
Wang J, Liu F, Song X, Li T. Association of 5p15.2 and 15q14 with high myopia in Tujia and Miao Chinese populations. BMC Ophthalmol 2020; 20:255. [PMID: 32586281 PMCID: PMC7318420 DOI: 10.1186/s12886-020-01516-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 06/12/2020] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND The polymorphisms rs6885224 and rs634990 have been reported to be associated with high myopia in many populations. As there is still no report on whether these two SNPs are associated with myopia in the Tujia and Miao minority areas of China, we conducted a replication study to evaluate the association of single-nucleotide polymorphisms in the regions 5p15.2 and 15q14 with high myopia in Tujia and Miao Chinese populations. METHODS We performed a comprehensive meta-analysis of 5831 cases and 7055 controls to assess whether rs6885224 in the 5p15.2 region and rs634990 in the 15q14 region are associated with high myopia. Our replication study enrolled 804 individuals. Genomic DNA was extracted from venous leukocytes, and these two SNPs were genotyped by Sanger sequencing. Allele and genotype frequencies were analysed using χ2 tests, and ORs and 95% CIs were calculated. RESULTS According to the results of the meta-analysis, rs6885224 in the CTNND2 gene showed no association with myopia [p = 0.222, OR = 1.154, 95% CI (0.917-1.452)]. Conversely, rs634990 in the 15q14 region did exhibit a significant correlation with myopia [p = 7.270 × 10- 7, OR = 0.817, 95% CI (0.754-0.885)]. In our replication study, no association with high myopia in the Tujia and Miao populations was found for rs634990 or rs6885224. The following were obtained by allele frequency analysis: rs6885224, p = 0.175, OR = 0.845, and 95% CI = 0.662-1.078; rs634990, p = 0.087, OR = 0.84, and the 95% CI = 0.687-1.026. Genotype frequency analysis yielded p = 0.376 for rs6885224 and p = 0.243 for rs634990. CONCLUSIONS Our meta-analysis results show that rs634990 was significantly associated with myopia but that rs6885224 was not. Nevertheless, in our replication study, these two SNPs showed no association with myopia in the Tujia and Miao Chinese populations. This is the first report involving Tujia and Miao ethnic groups from Enshi minority areas. However, the sample size needs to be expanded and more stringent inclusion and exclusion criteria need to be formulated to verify the findings.
Collapse
Affiliation(s)
- Junwen Wang
- Department of Hubei Minzu University Affiliated Enshi Clinical Medical School, The Central Hospital of Enshi Tujia And Miao Autonomous Prefecture, No.158, Wuyang Road, Enshi, 445000, Hubei Provence, China
| | - Fang Liu
- Department of Hubei Minzu University Affiliated Enshi Clinical Medical School, The Central Hospital of Enshi Tujia And Miao Autonomous Prefecture, No.158, Wuyang Road, Enshi, 445000, Hubei Provence, China.,Department of Eye Centre, Renmin Hospital of Wuhan University, Wuhan, 430060, Hubei, China
| | - Xiusheng Song
- Department of Hubei Minzu University Affiliated Enshi Clinical Medical School, The Central Hospital of Enshi Tujia And Miao Autonomous Prefecture, No.158, Wuyang Road, Enshi, 445000, Hubei Provence, China
| | - Tuo Li
- Department of Hubei Minzu University Affiliated Enshi Clinical Medical School, The Central Hospital of Enshi Tujia And Miao Autonomous Prefecture, No.158, Wuyang Road, Enshi, 445000, Hubei Provence, China.
| |
Collapse
|
6
|
Banerjee S, Wang Q, Zhao F, Tang G, So C, Tse D, To CH, Feng Y, Zhou X, Pan F. Increased Connexin36 Phosphorylation in AII Amacrine Cell Coupling of the Mouse Myopic Retina. Front Cell Neurosci 2020; 14:124. [PMID: 32547367 PMCID: PMC7278884 DOI: 10.3389/fncel.2020.00124] [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: 01/18/2020] [Accepted: 04/15/2020] [Indexed: 12/14/2022] Open
Abstract
Myopia is a substantial public health problem worldwide. In the myopic retina, distant images are focused in front of the photoreceptors. The cells and mechanisms for retinal signaling that account either for emmetropization (i.e., normal refraction) or for refractive errors have remained elusive. Gap junctions play a key component in enhancement of signal transmission in visual pathways. AII amacrine cells (ACs), coupled by connexin36, segregate signals into ON and OFF pathways. Coupling between AII ACs is actively modulated through phosphorylation at serine 293 via dopamine in the mouse retina. In this study, form deprivation mouse myopia models were used to evaluate the expression patterns of connexin36-positive plaques (structural assay) and the state of connexin36 phosphorylation (functional assay) in AII ACs, which was green fluorescent protein-expressing in the Fam81a mouse line. Single-cell RNA sequencing showed dopaminergic synapse and gap junction pathways of AII ACs were downregulated in the myopic retina, although Gjd2 mRNA expression remained the same. Compared with the normal refractive eye, phosphorylation of connexin36 was increased in the myopic retina, but expression of connexin36 remained unchanged. This increased phosphorylation of Cx36 could indicate increased functional gap junction coupling of AII ACs in the myopic retina, a possible adaptation to adjust to the altered noisy signaling status.
Collapse
Affiliation(s)
- Seema Banerjee
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Qin Wang
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Fuxin Zhao
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, The State Key Laboratory of Optometry, Ophthalmology and Vision Science, Wenzhou, China
| | - George Tang
- School of Clinical Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom
| | - Chunghim So
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Dennis Tse
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Chi-Ho To
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| | - Yun Feng
- Department of Ophthalmology, Peking University Third Hospital, Beijing, China
| | - Xiangtian Zhou
- School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical University, The State Key Laboratory of Optometry, Ophthalmology and Vision Science, Wenzhou, China
| | - Feng Pan
- Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong
| |
Collapse
|
7
|
Wong YL, Hysi P, Cheung G, Tedja M, Hoang QV, Tompson SWJ, Whisenhunt KN, Verhoeven V, Zhao W, Hess M, Wong CW, Kifley A, Hosoda Y, Haarman AEG, Hopf S, Laspas P, Sensaki S, Sim X, Miyake M, Tsujikawa A, Lamoureux E, Ohno-Matsui K, Nickels S, Mitchell P, Wong TY, Wang JJ, Hammond CJ, Barathi VA, Cheng CY, Yamashiro K, Young TL, Klaver CCW, Saw SM. Genetic variants linked to myopic macular degeneration in persons with high myopia: CREAM Consortium. PLoS One 2019; 14:e0220143. [PMID: 31415580 PMCID: PMC6695159 DOI: 10.1371/journal.pone.0220143] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 06/20/2019] [Indexed: 11/19/2022] Open
Abstract
Purpose To evaluate the roles of known myopia-associated genetic variants for development of myopic macular degeneration (MMD) in individuals with high myopia (HM), using case-control studies from the Consortium of Refractive Error and Myopia (CREAM). Methods A candidate gene approach tested 50 myopia-associated loci for association with HM and MMD, using meta-analyses of case-control studies comprising subjects of European and Asian ancestry aged 30 to 80 years from 10 studies. Fifty loci with the strongest associations with myopia were chosen from a previous published GWAS study. Highly myopic (spherical equivalent [SE] ≤ -5.0 diopters [D]) cases with MMD (N = 348), and two sets of controls were enrolled: (1) the first set included 16,275 emmetropes (SE ≤ -0.5 D); and (2) second set included 898 highly myopic subjects (SE ≤ -5.0 D) without MMD. MMD was classified based on the International photographic classification for pathologic myopia (META-PM). Results In the first analysis, comprising highly myopic cases with MMD (N = 348) versus emmetropic controls without MMD (N = 16,275), two SNPs were significantly associated with high myopia in adults with HM and MMD: (1) rs10824518 (P = 6.20E-07) in KCNMA1, which is highly expressed in human retinal and scleral tissues; and (2) rs524952 (P = 2.32E-16) near GJD2. In the second analysis, comprising highly myopic cases with MMD (N = 348) versus highly myopic controls without MMD (N = 898), none of the SNPs studied reached Bonferroni-corrected significance. Conclusions Of the 50 myopia-associated loci, we did not find any variant specifically associated with MMD, but the KCNMA1 and GJD2 loci were significantly associated with HM in highly myopic subjects with MMD, compared to emmetropes.
Collapse
Affiliation(s)
- Yee-Ling Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
- R&D Vision Sciences AMERA, Essilor International, Singapore, Singapore
| | - Pirro Hysi
- Section of Academic Ophthalmology, School of Life Course Sciences, King’s College London, London, United Kingdom
| | - Gemmy Cheung
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore
| | - Milly Tedja
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Quan V. Hoang
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
- Department of Ophthalmology, Columbia University Medical Center, New York, NY, United States of America
| | - Stuart W. J. Tompson
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison WI, United States of America
| | - Kristina N. Whisenhunt
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison WI, United States of America
| | - Virginie Verhoeven
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Wanting Zhao
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Moritz Hess
- Institute for Medical Biostatistics, Epidemiology and Informatics, University Medical Center of the Johannes Gutenberg—University Mainz, Mainz, Germany
- Institute of Medical Biometry and Statistics, Faculty of Medicine and Medical Center—University of Freiburg, Freiburg, Germany
| | - Chee-Wai Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
| | - Annette Kifley
- Department of Ophthalmology, Centre for Vision Research, Westmead Institute for Medical Research, University of Sydney, Sydney, New South Wales, Australia
| | - Yoshikatsu Hosoda
- Department of Ophthalmology and Visual Sciences, University Graduate School of Medicine, Kyoto, Japan
| | - Annechien E. G. Haarman
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Susanne Hopf
- Department of Ophthalmology, University Medical Center of the Johannes Gutenberg—University Mainz, Mainz, Germany
| | - Panagiotis Laspas
- Department of Ophthalmology, University Medical Center of the Johannes Gutenberg—University Mainz, Mainz, Germany
| | - Sonoko Sensaki
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
| | - Xueling Sim
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Masahiro Miyake
- Department of Ophthalmology and Visual Sciences, University Graduate School of Medicine, Kyoto, Japan
| | - Akitaka Tsujikawa
- Department of Ophthalmology and Visual Sciences, University Graduate School of Medicine, Kyoto, Japan
| | - Ecosse Lamoureux
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
| | - Kyoko Ohno-Matsui
- Department of Ophthalmology and Visual Science, Tokyo Medical and Dental University, Tokyo, Japan
| | - Stefan Nickels
- Department of Ophthalmology, University Medical Center of the Johannes Gutenberg—University Mainz, Mainz, Germany
| | - Paul Mitchell
- Department of Ophthalmology, Centre for Vision Research, Westmead Institute for Medical Research, University of Sydney, Sydney, New South Wales, Australia
| | - Tien-Yin Wong
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore
| | | | - Christopher J. Hammond
- Section of Academic Ophthalmology, School of Life Course Sciences, King’s College London, London, United Kingdom
| | - Veluchamy A. Barathi
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore
| | - Ching-Yu Cheng
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore
| | - Kenji Yamashiro
- Department of Ophthalmology and Visual Sciences, University Graduate School of Medicine, Kyoto, Japan
- Department of Ophthalmology, Otsu Red-Cross Hospital, Otsu, Japan
| | - Terri L. Young
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison WI, United States of America
| | - Caroline C. W. Klaver
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
- Department of Ophthalmology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Seang-Mei Saw
- Singapore Eye Research Institute, Singapore National Eye Centre, Singapore, Singapore
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
- Duke-NUS Medical School, Singapore, Singapore
- Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore, Singapore
- * E-mail:
| | | |
Collapse
|
8
|
Li L. Circadian Vision in Zebrafish: From Molecule to Cell and from Neural Network to Behavior. J Biol Rhythms 2019; 34:451-462. [DOI: 10.1177/0748730419863917] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Most visual system functions, such as opsin gene expression, retinal neural transmission, light perception, and visual sensitivity, display robust day-night rhythms. The rhythms persist in constant lighting conditions, suggesting the involvement of endogenous circadian clocks. While the circadian pacemakers that control the rhythms of animal behaviors are mostly found in the forebrain and midbrain, self-sustained circadian oscillators are also present in the neural retina, where they play important roles in the regulation of circadian vision. This review highlights some of the correlative studies of the circadian control of visual system functions in zebrafish. Because zebrafish maintain a high evolutionary proximity to mammals, the findings from zebrafish research may provide insights for a better understanding of the mechanisms of circadian vision in other vertebrate species including humans.
Collapse
Affiliation(s)
- Lei Li
- Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana
| |
Collapse
|
9
|
Yadav SC, Tetenborg S, Dedek K. Gap Junctions in A8 Amacrine Cells Are Made of Connexin36 but Are Differently Regulated Than Gap Junctions in AII Amacrine Cells. Front Mol Neurosci 2019; 12:99. [PMID: 31065239 PMCID: PMC6489437 DOI: 10.3389/fnmol.2019.00099] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 04/03/2019] [Indexed: 01/01/2023] Open
Abstract
In the mammalian retina, amacrine cells represent the most diverse cell class and are involved in the spatio-temporal processing of visual signals in the inner plexiform layer. They are connected to bipolar, other amacrine and ganglion cells, forming complex networks via electrical and chemical synapses. The small-field A8 amacrine cell was shown to receive non-selective glutamatergic input from OFF and ON cone bipolar cells at its bistratified dendrites in sublamina 1 and 4 of the inner plexiform layer. Interestingly, it was also shown to form electrical synapses with ON cone bipolar cells, thus resembling the rod pathway-specific AII amacrine cell. In contrast to the AII cell, however, the electrical synapses of A8 cells are poorly understood. Therefore, we made use of the Ier5-GFP mouse line, in which A8 cells are labeled by GFP, to study the gap junction composition and frequency in A8 cells. We found that A8 cells form <20 gap junctions per cell and these gap junctions consist of connexin36. Connexin36 is present at both OFF and ON dendrites of A8 cells, preferentially connecting A8 cells to type 1 OFF and type 6 and 7 ON bipolar cells and presumably other amacrine cells. Additionally, we show that the OFF dendrites of A8 cells co-stratify with the processes of dopaminergic amacrine cells from which they may receive GABAergic input via GABAA receptor subunit α3. As we found A8 cells to express dopamine receptor D1 (but not D2), we also tested whether A8 cell coupling is modulated by D1 receptor agonists and antagonists as was shown for the coupling of AII cells. However, this was not the case. In summary, our data suggests that A8 coupling is differently regulated than AII cells and may even be independent of ambient light levels and serve signal facilitation rather than providing a separate neuronal pathway.
Collapse
Affiliation(s)
- Shubhash C Yadav
- Animal Navigation/Neurosensorics, Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
| | - Stephan Tetenborg
- Animal Navigation/Neurosensorics, Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
| | - Karin Dedek
- Animal Navigation/Neurosensorics, Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany.,Research Center Neurosensory Science, University of Oldenburg, Oldenburg, Germany
| |
Collapse
|
10
|
Ghinia MG, Novelli E, Sajgo S, Badea TC, Strettoi E. Brn3a and Brn3b knockout mice display unvaried retinal fine structure despite major morphological and numerical alterations of ganglion cells. J Comp Neurol 2019; 527:187-211. [PMID: 27391320 PMCID: PMC5219957 DOI: 10.1002/cne.24072] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 06/07/2016] [Accepted: 06/30/2016] [Indexed: 01/21/2023]
Abstract
Ganglion cells (GCs), the retinal output neurons, receive synaptic inputs from bipolar and amacrine cells in the inner plexiform layer (IPL) and send information to the brain nuclei via the optic nerve. Although GCs constitute less than 1% of the total retinal cells, they occur in numerous types and are the first neurons formed during retinal development. Using Brn3a and Brn3b mutant mice in which the alkaline phosphatase gene was knocked-in (Badea et al. [Neuron] 2009;61:852-864; Badea and Nathans [Vision Res] 2011;51:269-279), we studied the general effects after gene removal on the retinal neuropil together with the consequences of lack of development of large numbers of GCs onto the remaining retinal neurons of the same class. We analyzed the morphology, number, and general architecture of various neuronal types presynaptic to GCs, searching for changes secondary to the decrement in the number of their postsynaptic partners, as well as the morphology and distribution of retinal astrocytes, for their strong topographical relation to GCs. We found that, despite GC losses, retinal organization in Brn3 null mice is remarkably similar to that of wild-type controls. J. Comp. Neurol. 527:187-211, 2019. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Miruna Georgiana Ghinia
- Neuroscience Institute of the Italian National Research Council, Pisa Research Campus, 56124 Pisa, Italy
- Retinal CIrcuit Development & Genetics Unit, Neurobiology–Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892
- Babeş Bolyai University, 400084 Cluj Napoca, Romania
| | - Elena Novelli
- Neuroscience Institute of the Italian National Research Council, Pisa Research Campus, 56124 Pisa, Italy
| | - Szilard Sajgo
- Retinal CIrcuit Development & Genetics Unit, Neurobiology–Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892
| | - Tudor Constantin Badea
- Retinal CIrcuit Development & Genetics Unit, Neurobiology–Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892
| | - Enrica Strettoi
- Neuroscience Institute of the Italian National Research Council, Pisa Research Campus, 56124 Pisa, Italy
| |
Collapse
|
11
|
Kunceviciene E, Sriubiene M, Liutkeviciene R, Miceikiene IT, Smalinskiene A. Heritability of myopia and its relation with GDJ2 and RASGRF1 genes in Lithuania. BMC Ophthalmol 2018; 18:124. [PMID: 29793445 PMCID: PMC5968600 DOI: 10.1186/s12886-018-0787-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 05/10/2018] [Indexed: 01/28/2023] Open
Abstract
Background This study aimed to assess heritability of myopia in Lithuania and evaluate both genes GJD2 (Gap Junction Protein, Delta 2) and RASGRF1 (RAS protein-specific guanine nucleotide-releasing factor 1) relation with myopia. Methods In this study Lithuanian twin population aged between 18 and 40 (n = 460) were examined. Single-nucleotide polymorphisms of the RASGRF1 (rs8027411) and GJD2 (rs634990) genes were assessed by real-time polymerase chain reaction method. Results Intrapair correlations for spherical equivalent in all twin pairs were significantly higher in MZ twin pairs r = 0.539 (p < 0.001, 95% CI 0.353–0.684) than in DZ twin pairs r = 0.203 (p < 0.01, 95% CI 0.0633–0.442) in myopia group. Correlations for spherical equivalent in emmetropia group were not significant in MZ twin pairs r = 0.091 (p > 0.05, 95% CI -0.215-0.381) and in DZ twin pairs r = − 0.220 (p > 0.05, 95% CI -0.587-0.222). The odds ratio (95% CI) were 2.7 (1.018–7.460) for combinations of genotypes of rs634990 CC and rs8027411 GT (p = 0.046). Conclusions Our studies have shown that the heritability of myopia makes 67.2% in Lithuania. Persons with combinations of genotypes rs634990 CC and rs8027411 GT have 2.7 times higher odds to have myopia.
Collapse
Affiliation(s)
- Edita Kunceviciene
- Institute of Biology Systems and Genetic Research, Lithuanian University of Health Sciences, 18 Tilzes St, Kaunas, Lithuania.
| | - Margarita Sriubiene
- Institute of Biology Systems and Genetic Research, Lithuanian University of Health Sciences, 18 Tilzes St, Kaunas, Lithuania
| | - Rasa Liutkeviciene
- Department of Ophthalmology, Lithuanian University of Health Sciences, 2 Eiveniu St, Kaunas, Lithuania
| | - Ilona T Miceikiene
- Institute of Biology Systems and Genetic Research, Lithuanian University of Health Sciences, 18 Tilzes St, Kaunas, Lithuania
| | - Alina Smalinskiene
- Institute of Biology Systems and Genetic Research, Lithuanian University of Health Sciences, 18 Tilzes St, Kaunas, Lithuania
| |
Collapse
|
12
|
Optimizing information processing in neuronal networks beyond critical states. PLoS One 2017; 12:e0184367. [PMID: 28922366 PMCID: PMC5603180 DOI: 10.1371/journal.pone.0184367] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 08/22/2017] [Indexed: 11/19/2022] Open
Abstract
Critical dynamics have been postulated as an ideal regime for neuronal networks in the brain, considering optimal dynamic range and information processing. Herein, we focused on how information entropy encoded in spatiotemporal activity patterns may vary in critical networks. We employed branching process based models to investigate how entropy can be embedded in spatiotemporal patterns. We determined that the information capacity of critical networks may vary depending on the manipulation of microscopic parameters. Specifically, the mean number of connections governed the number of spatiotemporal patterns in the networks. These findings are compatible with those of the real neuronal networks observed in specific brain circuitries, where critical behavior is necessary for the optimal dynamic range response but the uncertainty provided by high entropy as coded by spatiotemporal patterns is not required. With this, we were able to reveal that information processing can be optimized in neuronal networks beyond critical states.
Collapse
|
13
|
Kovács-Öller T, Raics K, Orbán J, Nyitrai M, Völgyi B. Developmental changes in the expression level of connexin36 in the rat retina. Cell Tissue Res 2014; 358:289-302. [PMID: 25110193 DOI: 10.1007/s00441-014-1967-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 07/09/2014] [Indexed: 02/03/2023]
Abstract
Connexin36 (Cx36) is the major gap junction forming protein in the brain and the retina; thus, alterations in its expression indicate changes in the corresponding circuitry. Many structural changes occur in the early postnatal retina before functional neuronal circuits are finalized, including those that incorporate gap junctions. To reveal the time-lapse formation of inner retinal gap junctions, we examine the developing postnatal rat retina from birth (P0) to young adult age (P20) and follow the expression of Cx36 in the mRNA and protein levels. We found a continuous elevation in the expression of both the Cx36 transcript and protein between P0 and P20 and a somewhat delayed Cx36 plaque formation throughout the inner plexiform layer (IPL) starting at P10. By using tristratificated calretinin positive (CaR(+)) fibers in the IPL as a guide, we detected a clear preference of Cx36 plaques for the ON sublamina from the earliest time of detection. This distributional preference became more pronounced at P15 and P20 due to the emergence and widespread expression of large (>0.1 μm(2)) Cx36 plaques in the ON sublamina. Finally, we showed that parvalbumin-positive (PV(+)) AII amacrine cell dendrites colocalize with Cx36 plaques as early as P10 in strata 3 and 4, whereas colocalizations in stratum 5 became characteristic only around P20. We conclude that Cx36 expression in the rat IPL displays a characteristic succession of changes during retinogenesis reflecting the formation of the underlying electrical synaptic circuitry. In particular, AII cell gap junctions, first formed with ON cone bipolar cells and later with other AII amacrine cells, accounted for the observed Cx36 expressional changes.
Collapse
Affiliation(s)
- Tamás Kovács-Öller
- Department of Experimental Zoology and Neurobiology, University of Pécs, Pécs, Ifjúság street 6, Hungary
| | | | | | | | | |
Collapse
|
14
|
Palacios-Muñoz A, Escobar MJ, Vielma A, Araya J, Astudillo A, Valdivia G, García IE, Hurtado J, Schmachtenberg O, Martínez AD, Palacios AG. Role of connexin channels in the retinal light response of a diurnal rodent. Front Cell Neurosci 2014; 8:249. [PMID: 25202238 PMCID: PMC4142540 DOI: 10.3389/fncel.2014.00249] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Accepted: 08/05/2014] [Indexed: 01/02/2023] Open
Abstract
Several studies have shown that connexin channels play an important role in retinal neural coding in nocturnal rodents. However, the contribution of these channels to signal processing in the retina of diurnal rodents remains unclear. To gain insight into this problem, we studied connexin expression and the contribution of connexin channels to the retinal light response in the diurnal rodent Octodon degus (degu) compared to rat, using in vivo ERG recording under scotopic and photopic light adaptation. Analysis of the degu genome showed that the common retinal connexins present a high degree of homology to orthologs expressed in other mammals, and expression of Cx36 and Cx43 was confirmed in degu retina. Cx36 localized mainly to the outer and inner plexiform layers (IPLs), while Cx43 was expressed mostly in cells of the retinal pigment epithelium. Under scotopic conditions, the b-wave response amplitude was strongly reduced by 18-β-glycyrrhetinic acid (β-GA) (−45.1% in degu, compared to −52.2% in rat), suggesting that connexins are modulating this response. Remarkably, under photopic adaptation, β-GA increased the ERG b-wave amplitude in degu (+107.2%) while reducing it in rat (−62.3%). Moreover, β-GA diminished the spontaneous action potential firing rate in ganglion cells (GCs) and increased the response latency of ON and OFF GCs. Our results support the notion that connexins exert a fine-tuning control of the retinal light response and have an important role in retinal neural coding.
Collapse
Affiliation(s)
- Angelina Palacios-Muñoz
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso Valparaíso, Chile
| | - Maria J Escobar
- Departamento de Electrónica, Universidad Técnico Federico Santa María Valparaíso, Chile
| | - Alex Vielma
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso Valparaíso, Chile
| | - Joaquín Araya
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso Valparaíso, Chile
| | - Aland Astudillo
- Departamento de Electrónica, Universidad Técnico Federico Santa María Valparaíso, Chile
| | - Gonzalo Valdivia
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso Valparaíso, Chile
| | - Isaac E García
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso Valparaíso, Chile
| | - José Hurtado
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso Valparaíso, Chile ; Instituto de Sistemas Complejos de Valparaíso Valparaíso, Chile
| | - Oliver Schmachtenberg
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso Valparaíso, Chile
| | - Agustín D Martínez
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso Valparaíso, Chile
| | - Adrian G Palacios
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Universidad de Valparaíso Valparaíso, Chile ; Instituto de Sistemas Complejos de Valparaíso Valparaíso, Chile
| |
Collapse
|
15
|
Walter LT, Higa GSV, Schmeltzer C, Sousa E, Kinjo ER, Rüdiger S, Hamassaki DE, Cerchiaro G, Kihara AH. Functional regulation of neuronal nitric oxide synthase expression and activity in the rat retina. Exp Neurol 2014; 261:510-7. [PMID: 25116452 DOI: 10.1016/j.expneurol.2014.07.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 07/16/2014] [Accepted: 07/29/2014] [Indexed: 11/19/2022]
Abstract
In the nervous system within physiological conditions, nitric oxide (NO) production depends on the activity of nitric oxide synthases (NOSs), and particularly on the expression of the neuronal isoform (nNOS). In the sensory systems, the role of NO is poorly understood. In this study, we identified nNOS-positive cells in the inner nuclear layer (INL) of the rat retina, with distinct characteristics such as somata size, immunolabeling level and location. Employing mathematical cluster analysis, we determined that nNOS amacrine cells are formed by two distinct populations. We next investigated the molecular identity of these cells, which did not show colocalization with calbindin (CB), choline acetyltransferase (ChAT), parvalbumin (PV) or protein kinase C (PKC), and only partial colocalization with calretinin (CR), revealing the accumulation of nNOS in specific amacrine cell populations. To access the functional, circuitry-related roles of these cells, we performed experiments after adaptation to different ambient light conditions. After 24h of dark-adaptation, we detected a subtle, yet statistically significant decrease in nNOS transcript levels, which returned to steady-state levels after 24h of normal light-dark cycle, revealing that nNOS expression is governed by ambient light conditions. Employing electron paramagnetic resonance (EPR), we demonstrated that dark-adaptation decreases NO production in the retina. Furthermore, nNOS accumulation changed in the dark-adapted retinas, with a general reduction in the inner plexiform layer. Finally, computational analysis based on clustering techniques revealed that dark-adaptation differently affected both types of nNOS-positive amacrine cells. Taken together, our data disclosed functional regulation of nNOS expression and activity, disclosing new circuitry-related roles of nNOS-positive cells. More importantly, this study indicated unsuspected roles for NO in the sensory systems, particularly related to adaptation to ambient demands.
Collapse
Affiliation(s)
- Lais Takata Walter
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Brazil
| | - Guilherme Shigueto Vilar Higa
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Brazil; Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
| | | | - Erica Sousa
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Brazil
| | - Erika Reime Kinjo
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Brazil
| | - Sten Rüdiger
- Institute of Physics, Humboldt University at Berlin, Germany
| | - Dânia Emi Hamassaki
- Departamento de Biologia Celular e do Desenvolvimento, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil
| | - Giselle Cerchiaro
- Núcleo de Cognição e Sistemas Complexos, Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Brazil
| | - Alexandre Hiroaki Kihara
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Brazil; Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil.
| |
Collapse
|
16
|
Sherwin JC, Mackey DA. Update on the epidemiology and genetics of myopic refractive error. EXPERT REVIEW OF OPHTHALMOLOGY 2014. [DOI: 10.1586/eop.12.81] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
17
|
de Sousa É, Walter LT, Higa GSV, Casado OAN, Kihara AH. Developmental and functional expression of miRNA-stability related genes in the nervous system. PLoS One 2013; 8:e56908. [PMID: 23700402 PMCID: PMC3659046 DOI: 10.1371/journal.pone.0056908] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 01/15/2013] [Indexed: 11/19/2022] Open
Abstract
In the nervous system, control of gene expression by microRNAs (miRNAs) has been investigated in fundamental processes, such as development and adaptation to ambient demands. The action of these short nucleotide sequences on specific genes depends on intracellular concentration, which in turn reflects the balance of biosynthesis and degradation. Whereas mechanisms underlying miRNA biogenesis has been investigated in recent studies, little is known about miRNA-stability related proteins. We first detected two genes in the retina that have been associated to miRNA stability, XRN2 and PAPD4. These genes are highly expressed during retinal development, however with distinct subcellular localization. We investigated whether these proteins are regulated during specific phases of the cell cycle. Combined analyses of nuclei position in neuroblastic layer and labeling using anti-cyclin D1 revealed that both proteins do not accumulate in S or M phases of the cell cycle, being poorly expressed in progenitor cells. Indeed, XRN2 and PAPD4 were observed mainly after neuronal differentiation, since low expression was also observed in astrocytes, endothelial and microglial cells. XRN2 and PAPD4 are expressed in a wide variety of neurons, including horizontal, amacrine and ganglion cells. To evaluate the functional role of both genes, we carried out experiments addressed to the retinal adaptation in response to different ambient light conditions. PAPD4 is upregulated after 3 and 24 hours of dark- adaptation, revealing that accumulation of this protein is governed by ambient light levels. Indeed, the fast and functional regulation of PAPD4 was not related to changes in gene expression, disclosing that control of protein levels occurs by post-transcriptional mechanisms. Furthermore, we were able to quantify changes in PAPD4 in specific amacrine cells after dark -adaptation, suggesting for circuitry-related roles in visual perception. In summary, in this study we first described the ontogenesis and functional expression of these two miRNA-stability related proteins in the retina.
Collapse
Affiliation(s)
- Érica de Sousa
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, SP, Brasil
| | - Lais Takata Walter
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, SP, Brasil
| | - Guilherme Shigueto Vilar Higa
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, SP, Brasil
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Otávio Augusto Nocera Casado
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, SP, Brasil
| | - Alexandre Hiroaki Kihara
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, SP, Brasil
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP, Brasil
- * E-mail:
| |
Collapse
|
18
|
Li H, Zhang Z, Blackburn MR, Wang SW, Ribelayga CP, O'Brien J. Adenosine and dopamine receptors coregulate photoreceptor coupling via gap junction phosphorylation in mouse retina. J Neurosci 2013; 33:3135-50. [PMID: 23407968 PMCID: PMC3711184 DOI: 10.1523/jneurosci.2807-12.2013] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 12/20/2012] [Accepted: 12/24/2012] [Indexed: 11/21/2022] Open
Abstract
Gap junctions in retinal photoreceptors suppress voltage noise and facilitate input of rod signals into the cone pathway during mesopic vision. These synapses are highly plastic and regulated by light and circadian clocks. Recent studies have revealed an important role for connexin36 (Cx36) phosphorylation by protein kinase A (PKA) in regulating cell-cell coupling. Dopamine is a light-adaptive signal in the retina, causing uncoupling of photoreceptors via D4 receptors (D4R), which inhibit adenylyl cyclase (AC) and reduce PKA activity. We hypothesized that adenosine, with its extracellular levels increasing in darkness, may serve as a dark signal to coregulate photoreceptor coupling through modulation of gap junction phosphorylation. Both D4R and A2a receptor (A2aR) mRNAs were present in photoreceptors, inner nuclear layer neurons, and ganglion cells in C57BL/6 mouse retina, and showed cyclic expression with partially overlapping rhythms. Pharmacologically activating A2aR or inhibiting D4R in light-adapted daytime retina increased photoreceptor coupling. Cx36 among photoreceptor terminals, representing predominantly rod-cone gap junctions but possibly including some rod-rod and cone-cone gap junctions, was phosphorylated in a PKA-dependent manner by the same treatments. Conversely, inhibiting A2aR or activating D4R in daytime dark-adapted retina decreased Cx36 phosphorylation with similar PKA dependence. A2a-deficient mouse retina showed defective regulation of photoreceptor gap junction phosphorylation, fairly regular dopamine release, and moderately downregulated expression of D4R and AC type 1 mRNA. We conclude that adenosine and dopamine coregulate photoreceptor coupling through opposite action on the PKA pathway and Cx36 phosphorylation. In addition, loss of the A2aR hampered D4R gene expression and function.
Collapse
MESH Headings
- Adenylyl Cyclases/metabolism
- Animals
- Chromatography, High Pressure Liquid
- Connexins/metabolism
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Dark Adaptation/physiology
- Gap Junctions/metabolism
- Gap Junctions/physiology
- Gene Expression/physiology
- Image Processing, Computer-Assisted
- Immunohistochemistry
- In Situ Hybridization
- In Vitro Techniques
- Mice
- Mice, Inbred C57BL
- Phosphorylation
- Real-Time Polymerase Chain Reaction
- Receptors, Adenosine A2/genetics
- Receptors, Adenosine A2/physiology
- Receptors, Dopamine/genetics
- Receptors, Dopamine/physiology
- Receptors, Dopamine D4/biosynthesis
- Receptors, Dopamine D4/genetics
- Receptors, Purinergic P1/genetics
- Receptors, Purinergic P1/physiology
- Retinal Cone Photoreceptor Cells/physiology
- Retinal Rod Photoreceptor Cells/physiology
- Gap Junction delta-2 Protein
Collapse
Affiliation(s)
- Hongyan Li
- Richard S. Ruiz, MD, Department of Ophthalmology and Visual Science, The University of Texas Medical School and
| | - Zhijing Zhang
- Richard S. Ruiz, MD, Department of Ophthalmology and Visual Science, The University of Texas Medical School and
| | - Michael R. Blackburn
- Department of Biochemistry and Molecular Biology, The University of Texas Medical School, Houston, Texas 77030; and
- Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - Steven W. Wang
- Richard S. Ruiz, MD, Department of Ophthalmology and Visual Science, The University of Texas Medical School and
- Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - Christophe P. Ribelayga
- Richard S. Ruiz, MD, Department of Ophthalmology and Visual Science, The University of Texas Medical School and
- Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030
| | - John O'Brien
- Richard S. Ruiz, MD, Department of Ophthalmology and Visual Science, The University of Texas Medical School and
- Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas 77030
| |
Collapse
|
19
|
Völgyi B, Kovács-Oller T, Atlasz T, Wilhelm M, Gábriel R. Gap junctional coupling in the vertebrate retina: variations on one theme? Prog Retin Eye Res 2013; 34:1-18. [PMID: 23313713 DOI: 10.1016/j.preteyeres.2012.12.002] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 12/18/2012] [Accepted: 12/28/2012] [Indexed: 10/27/2022]
Abstract
Gap junctions connect cells in the bodies of all multicellular organisms, forming either homologous or heterologous (i.e. established between identical or different cell types, respectively) cell-to-cell contacts by utilizing identical (homotypic) or different (heterotypic) connexin protein subunits. Gap junctions in the nervous system serve electrical signaling between neurons, thus they are also called electrical synapses. Such electrical synapses are particularly abundant in the vertebrate retina where they are specialized to form links between neurons as well as glial cells. In this article, we summarize recent findings on retinal cell-to-cell coupling in different vertebrates and identify general features in the light of the evergrowing body of data. In particular, we describe and discuss tracer coupling patterns, connexin proteins, junctional conductances and modulatory processes. This multispecies comparison serves to point out that most features are remarkably conserved across the vertebrate classes, including (i) the cell types connected via electrical synapses; (ii) the connexin makeup and the conductance of each cell-to-cell contact; (iii) the probable function of each gap junction in retinal circuitry; (iv) the fact that gap junctions underlie both electrical and/or tracer coupling between glial cells. These pan-vertebrate features thus demonstrate that retinal gap junctions have changed little during the over 500 million years of vertebrate evolution. Therefore, the fundamental architecture of electrically coupled retinal circuits seems as old as the retina itself, indicating that gap junctions deeply incorporated in retinal wiring from the very beginning of the eye formation of vertebrates. In addition to hard wiring provided by fast synaptic transmitter-releasing neurons and soft wiring contributed by peptidergic, aminergic and purinergic systems, electrical coupling may serve as the 'skeleton' of lateral processing, enabling important functions such as signal averaging and synchronization.
Collapse
Affiliation(s)
- Béla Völgyi
- Department of Ophthalmology, School of Medicine, New York University, 550 First Avenue, MSB 149, New York, NY 10016, USA.
| | | | | | | | | |
Collapse
|
20
|
Manchanda K, Yadav AC, Ramaswamy R. Scaling behavior in probabilistic neuronal cellular automata. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:012704. [PMID: 23410356 DOI: 10.1103/physreve.87.012704] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 11/16/2012] [Indexed: 06/01/2023]
Abstract
We study a neural network model of interacting stochastic discrete two-state cellular automata on a regular lattice. The system is externally tuned to a critical point which varies with the degree of stochasticity (or the effective temperature). There are avalanches of neuronal activity, namely, spatially and temporally contiguous sites of activity; a detailed numerical study of these activity avalanches is presented, and single, joint, and marginal probability distributions are computed. At the critical point, we find that the scaling exponents for the variables are in good agreement with a mean-field theory.
Collapse
Affiliation(s)
- Kaustubh Manchanda
- School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | | | | |
Collapse
|
21
|
Paschon V, Higa GSV, Resende RR, Britto LRG, Kihara AH. Blocking of connexin-mediated communication promotes neuroprotection during acute degeneration induced by mechanical trauma. PLoS One 2012; 7:e45449. [PMID: 23029016 PMCID: PMC3447938 DOI: 10.1371/journal.pone.0045449] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 08/22/2012] [Indexed: 01/27/2023] Open
Abstract
Accruing evidence indicates that connexin (Cx) channels in the gap junctions (GJ) are involved in neurodegeneration after injury. However, studies using KO animal models endowed apparently contradictory results in relation to the role of coupling in neuroprotection. We analyzed the role of Cx-mediated communication in a focal lesion induced by mechanical trauma of the retina, a model that allows spatial and temporal definition of the lesion with high reproducibility, permitting visualization of the focus, penumbra and adjacent areas. Cx36 and Cx43 exhibited distinct gene expression and protein levels throughout the neurodegeneration progress. Cx36 was observed close to TUNEL-positive nuclei, revealing the presence of this protein surrounding apoptotic cells. The functional role of cell coupling was assessed employing GJ blockers and openers combined with lactate dehydrogenase (LDH) assay, a direct method for evaluating cell death/viability. Carbenoxolone (CBX), a broad-spectrum GJ blocker, reduced LDH release after 4 hours, whereas quinine, a Cx36-channel specific blocker, decreased LDH release as early as 1 hour after lesion. Furthermore, analysis of dying cell distribution confirmed that the use of GJ blockers reduced apoptosis spread. Accordingly, blockade of GJ communication during neurodegeneration with quinine, but not CBX, caused downregulation of initial and effector caspases. To summarize, we observed specific changes in Cx gene expression and protein distribution during the progress of retinal degeneration, indicating the participation of these elements in acute neurodegeneration processes. More importantly, our results revealed that direct control of GJ channels permeability may take part in reliable neuroprotection strategies aimed to rapid, fast treatment of mechanical trauma in the retina.
Collapse
Affiliation(s)
- Vera Paschon
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, São Paulo, Brazil
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Guilherme Shigueto Vilar Higa
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, São Paulo, Brazil
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Rodrigo Ribeiro Resende
- Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Luiz Roberto G. Britto
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
| | - Alexandre Hiroaki Kihara
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, São Paulo, Brazil
- Departamento de Fisiologia e Biofísica, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, São Paulo, Brazil
- * E-mail:
| |
Collapse
|
22
|
Verhoeven VJM, Hysi PG, Saw SM, Vitart V, Mirshahi A, Guggenheim JA, Cotch MF, Yamashiro K, Baird PN, Mackey DA, Wojciechowski R, Ikram MK, Hewitt AW, Duggal P, Janmahasatian S, Khor CC, Fan Q, Zhou X, Young TL, Tai ES, Goh LK, Li YJ, Aung T, Vithana E, Teo YY, Tay W, Sim X, Rudan I, Hayward C, Wright AF, Polasek O, Campbell H, Wilson JF, Fleck BW, Nakata I, Yoshimura N, Yamada R, Matsuda F, Ohno-Matsui K, Nag A, McMahon G, Pourcain BS, Lu Y, Rahi JS, Cumberland PM, Bhattacharya S, Simpson CL, Atwood LD, Li X, Raffel LJ, Murgia F, Portas L, Despriet DDG, van Koolwijk LME, Wolfram C, Lackner KJ, Tönjes A, Mägi R, Lehtimäki T, Kähönen M, Esko T, Metspalu A, Rantanen T, Pärssinen O, Klein BE, Meitinger T, Spector TD, Oostra BA, Smith AV, de Jong PTVM, Hofman A, Amin N, Karssen LC, Rivadeneira F, Vingerling JR, Eiríksdóttir G, Gudnason V, Döring A, Bettecken T, Uitterlinden AG, Williams C, Zeller T, Castagné R, Oexle K, van Duijn CM, Iyengar SK, Mitchell P, Wang JJ, Höhn R, Pfeiffer N, Bailey-Wilson JE, Stambolian D, Wong TY, Hammond CJ, Klaver CCW. Large scale international replication and meta-analysis study confirms association of the 15q14 locus with myopia. The CREAM consortium. Hum Genet 2012; 131:1467-80. [PMID: 22665138 PMCID: PMC3418496 DOI: 10.1007/s00439-012-1176-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2012] [Accepted: 04/27/2012] [Indexed: 12/14/2022]
Abstract
Myopia is a complex genetic disorder and a common cause of visual impairment among working age adults. Genome-wide association studies have identified susceptibility loci on chromosomes 15q14 and 15q25 in Caucasian populations of European ancestry. Here, we present a confirmation and meta-analysis study in which we assessed whether these two loci are also associated with myopia in other populations. The study population comprised 31 cohorts from the Consortium of Refractive Error and Myopia (CREAM) representing 4 different continents with 55,177 individuals; 42,845 Caucasians and 12,332 Asians. We performed a meta-analysis of 14 single nucleotide polymorphisms (SNPs) on 15q14 and 5 SNPs on 15q25 using linear regression analysis with spherical equivalent as a quantitative outcome, adjusted for age and sex. We calculated the odds ratio (OR) of myopia versus hyperopia for carriers of the top-SNP alleles using a fixed effects meta-analysis. At locus 15q14, all SNPs were significantly replicated, with the lowest P value 3.87 × 10(-12) for SNP rs634990 in Caucasians, and 9.65 × 10(-4) for rs8032019 in Asians. The overall meta-analysis provided P value 9.20 × 10(-23) for the top SNP rs634990. The risk of myopia versus hyperopia was OR 1.88 (95 % CI 1.64, 2.16, P < 0.001) for homozygous carriers of the risk allele at the top SNP rs634990, and OR 1.33 (95 % CI 1.19, 1.49, P < 0.001) for heterozygous carriers. SNPs at locus 15q25 did not replicate significantly (P value 5.81 × 10(-2) for top SNP rs939661). We conclude that common variants at chromosome 15q14 influence susceptibility for myopia in Caucasian and Asian populations world-wide.
Collapse
Affiliation(s)
- Virginie J. M. Verhoeven
- Department of Ophthalmology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Pirro G. Hysi
- Department of Twin Research and Genetic Epidemiology, King’s College London, St. Thomas’ Hospital, London, UK
| | - Seang-Mei Saw
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
| | - Veronique Vitart
- Medical Research Council Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Alireza Mirshahi
- Department of Ophthalmology, J. Gutenberg University Medical Center, Mainz, Germany
| | | | - Mary Frances Cotch
- Division of Epidemiology and Clinical Applications, National Eye Institute, Intramural Research Program, National Institutes of Health, Bethesda, USA
| | - Kenji Yamashiro
- Department of Ophthalmology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Paul N. Baird
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Australia
| | - David A. Mackey
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Australia
- Centre for Ophthalmology and Visual Science, Lions Eye Institute, University of Western Australia, Perth, Australia
| | - Robert Wojciechowski
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
- Inherited Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Baltimore, USA
| | - M. Kamran Ikram
- Department of Ophthalmology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
- Department of Ophthalmology, National University Health System, National University of Singapore, Singapore, Singapore
| | - Alex W. Hewitt
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Australia
| | - Priya Duggal
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - Sarayut Janmahasatian
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, USA
| | - Chiea-Chuen Khor
- Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore, Singapore
| | - Qiao Fan
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Xin Zhou
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Terri L. Young
- Center for Human Genetics, Duke University Medical Center, Durham, USA
| | - E-Shyong Tai
- Department of Medicine, National University of Singapore, Singapore, Singapore
| | - Liang-Kee Goh
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
- Duke-National University of Singapore Graduate Medical School, Singapore, Singapore
| | - Yi-Ju Li
- Center for Human Genetics, Duke University Medical Center, Durham, USA
| | - Tin Aung
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Department of Ophthalmology, National University Health System, National University of Singapore, Singapore, Singapore
| | - Eranga Vithana
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Department of Ophthalmology, National University Health System, National University of Singapore, Singapore, Singapore
| | - Yik-Ying Teo
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
- Department of Statistics and Applied Probability, National University of Singapore, Singapore, Singapore
- Centre for Molecular Epidemiology, National University of Singapore, Singapore, Singapore
| | - Wanting Tay
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
| | - Xueling Sim
- Centre for Molecular Epidemiology, National University of Singapore, Singapore, Singapore
| | - Igor Rudan
- Centre for Population Health Sciences, University of Edinburgh, Edinburgh, UK
| | - Caroline Hayward
- Medical Research Council Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Alan F. Wright
- Medical Research Council Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Ozren Polasek
- Faculty of Medicine, University of Split, Split, Croatia
| | - Harry Campbell
- Centre for Population Health Sciences, University of Edinburgh, Edinburgh, UK
| | - James F. Wilson
- Centre for Population Health Sciences, University of Edinburgh, Edinburgh, UK
| | | | - Isao Nakata
- Department of Ophthalmology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Nagahisa Yoshimura
- Department of Ophthalmology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Ryo Yamada
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Fumihiko Matsuda
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Kyoko Ohno-Matsui
- Department of Ophthalmology and Visual Science, Tokyo Medical and Dental University, Tokyo, Japan
| | - Abhishek Nag
- Department of Twin Research and Genetic Epidemiology, King’s College London, St. Thomas’ Hospital, London, UK
| | - George McMahon
- School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Beate St. Pourcain
- School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Yi Lu
- Department of Genetics and Population Health, Queensland Institute of Medical Research, Brisbane, Australia
| | - Jugnoo S. Rahi
- Medical Research Council Centre of Epidemiology for Child Health, Institute of Child Health, University College London, London, UK
- Institute of Ophthalmology, University College London, London, UK
| | - Phillippa M. Cumberland
- Medical Research Council Centre of Epidemiology for Child Health, Institute of Child Health, University College London, London, UK
- Ulverscroft Vision Research Group, University College London, London, UK
| | | | - Claire L. Simpson
- Inherited Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Baltimore, USA
| | - Larry D. Atwood
- Department of Neurology, Boston University School of Medicine, Boston, USA
| | - Xiaohui Li
- Medical Genetics Institute, Cedars-Sinai Medical Center, Los Angeles, USA
| | - Leslie J. Raffel
- Medical Genetics Institute, Cedars-Sinai Medical Center, Los Angeles, USA
| | - Federico Murgia
- Institute of Population Genetics, National Research Council, Sassari, Italy
| | - Laura Portas
- Institute of Population Genetics, National Research Council, Sassari, Italy
| | - Dominiek D. G. Despriet
- Department of Ophthalmology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Leonieke M. E. van Koolwijk
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
- Glaucoma Service, The Rotterdam Eye Hospital, Rotterdam, The Netherlands
| | - Christian Wolfram
- Department of Ophthalmology, J. Gutenberg University Medical Center, Mainz, Germany
| | - Karl J. Lackner
- Department of Ophthalmology, J. Gutenberg University Medical Center, Mainz, Germany
- Institute of Clinical Chemistry and Laboratory Medicine, J. Gutenberg University Medical Center, Mainz, Germany
| | - Anke Tönjes
- Department of Medicine, University of Leipzig, Leipzig, Germany
- Integrated Research and Treatment Center (IFB) AdiposityDiseases, University of Leipzig, Leipzig, Germany
| | - Reedik Mägi
- Estonian Genome Center, University of Tartu, Tartu, Estonia
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, UK
| | - Terho Lehtimäki
- Department of Clinical Chemistry, Fimlab Laboratories, Tampere University Hospital, Tampere, Finland
- University of Tampere School of Medicine, Tampere, Finland
| | - Mika Kähönen
- Department of Clinical Physiology, Tampere University Hospital, Tampere, Finland
- Department of Clinical Physiology, University of Tampere School of Medicine, Tampere, Finland
| | - Tõnu Esko
- Estonian Genome Center, University of Tartu, Tartu, Estonia
| | | | - Taina Rantanen
- Department of Health Sciences, Gerontology Research Center, University of Jyväskylä, Jyväskylä, Finland
| | - Olavi Pärssinen
- Department of Ophthalmology, Central Hospital of Central Finland, Jyväskylä, Finland
| | - Barbara E. Klein
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, USA
| | - Thomas Meitinger
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology I, Neuherberg, Germany
- Institute of Human Genetics, Technical University Munich, Munich, Germany
| | - Timothy D. Spector
- Department of Twin Research and Genetic Epidemiology, King’s College London, St. Thomas’ Hospital, London, UK
| | - Ben A. Oostra
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Albert V. Smith
- Department of Medicine, University of Iceland, Reykjavik, Iceland
- Icelandic Heart Association, Kopavogur, Iceland
| | - Paulus T. V. M. de Jong
- Department of Clinical and Molecular Ophthalmogenetics, Netherlands Institute of Neurosciences (NIN), An Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands
- Department of Ophthalmology, Academic Medical Center, Amsterdam, The Netherlands
| | - Albert Hofman
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Najaf Amin
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Lennart C. Karssen
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Fernando Rivadeneira
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Johannes R. Vingerling
- Department of Ophthalmology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | | | - Vilmundur Gudnason
- Department of Medicine, University of Iceland, Reykjavik, Iceland
- Icelandic Heart Association, Kopavogur, Iceland
| | - Angela Döring
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Epidemiology II, Neuherberg, Germany
| | - Thomas Bettecken
- Center for Applied Genotyping, Max Planck Institute of Psychiatry, German Research Institute of Psychiatry, Munich, Germany
| | - André G. Uitterlinden
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
- Department of Internal Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Cathy Williams
- Centre for Child and Adolescent Health, University of Bristol, Bristol, UK
| | - Tanja Zeller
- Clinic for General and Interventional Cardiology, University Heart Center Hamburg, Hamburg, Germany
| | - Raphaële Castagné
- INSERM UMRS 937, Pierre and Marie Curie University (UPMC, Paris 6) and Medical School, Paris, France
| | - Konrad Oexle
- Institute of Human Genetics, Technical University Munich, Munich, Germany
| | - Cornelia M. van Duijn
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Sudha K. Iyengar
- Department of Epidemiology and Biostatistics, Case Western Reserve University, Cleveland, USA
| | - Paul Mitchell
- Department of Ophthalmology, Centre for Vision Research, Westmead Millennium Institute, University of Sydney, Sydney, Australia
| | - Jie Jin Wang
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, University of Melbourne, Melbourne, Australia
- Department of Ophthalmology, Centre for Vision Research, Westmead Millennium Institute, University of Sydney, Sydney, Australia
| | - René Höhn
- Department of Ophthalmology, J. Gutenberg University Medical Center, Mainz, Germany
| | - Norbert Pfeiffer
- Department of Ophthalmology, J. Gutenberg University Medical Center, Mainz, Germany
| | - Joan E. Bailey-Wilson
- Inherited Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Baltimore, USA
| | - Dwight Stambolian
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, USA
| | - Tien-Yin Wong
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
- Singapore National Eye Centre, Singapore Eye Research Institute, Singapore, Singapore
- Department of Ophthalmology, National University Health System, National University of Singapore, Singapore, Singapore
| | - Christopher J. Hammond
- Department of Twin Research and Genetic Epidemiology, King’s College London, St. Thomas’ Hospital, London, UK
| | - Caroline C. W. Klaver
- Department of Ophthalmology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
- Department of Epidemiology, Erasmus Medical Center, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| |
Collapse
|
23
|
Pereda AE, Curti S, Hoge G, Cachope R, Flores CE, Rash JE. Gap junction-mediated electrical transmission: regulatory mechanisms and plasticity. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1828:134-46. [PMID: 22659675 DOI: 10.1016/j.bbamem.2012.05.026] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 02/24/2012] [Revised: 05/16/2012] [Accepted: 05/23/2012] [Indexed: 02/08/2023]
Abstract
The term synapse applies to cellular specializations that articulate the processing of information within neural circuits by providing a mechanism for the transfer of information between two different neurons. There are two main modalities of synaptic transmission: chemical and electrical. While most efforts have been dedicated to the understanding of the properties and modifiability of chemical transmission, less is still known regarding the plastic properties of electrical synapses, whose structural correlate is the gap junction. A wealth of data indicates that, rather than passive intercellular channels, electrical synapses are more dynamic and modifiable than was generally perceived. This article will discuss the factors determining the strength of electrical transmission and review current evidence demonstrating its dynamic properties. Like their chemical counterparts, electrical synapses can also be plastic and modifiable. This article is part of a Special Issue entitled: The Communicating junctions, roles and dysfunctions.
Collapse
Affiliation(s)
- Alberto E Pereda
- Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA.
| | | | | | | | | | | |
Collapse
|
24
|
Gollo LL, Kinouchi O, Copelli M. Statistical physics approach to dendritic computation: the excitable-wave mean-field approximation. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 85:011911. [PMID: 22400595 DOI: 10.1103/physreve.85.011911] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 11/23/2011] [Indexed: 05/31/2023]
Abstract
We analytically study the input-output properties of a neuron whose active dendritic tree, modeled as a Cayley tree of excitable elements, is subjected to Poisson stimulus. Both single-site and two-site mean-field approximations incorrectly predict a nonequilibrium phase transition which is not allowed in the model. We propose an excitable-wave mean-field approximation which shows good agreement with previously published simulation results [Gollo et al., PLoS Comput. Biol. 5, e1000402 (2009)] and accounts for finite-size effects. We also discuss the relevance of our results to experiments in neuroscience, emphasizing the role of active dendrites in the enhancement of dynamic range and in gain control modulation.
Collapse
Affiliation(s)
- Leonardo L Gollo
- IFISC (CSIC - UIB), Instituto de Física Interdisciplinar y Sistemas Complejos, Campus Universitat Illes Balears, E-07122 Palma de Mallorca, Spain.
| | | | | |
Collapse
|
25
|
Abstract
Using both NADPH diaphorase and anti-nNOS antibodies, we have identified-from retinal flatmounts-neuronal types in the inner retina of the chicken that are likely to be nitrergic. The two methods gave similar results and yielded a total of 15 types of neurons, comprising 9 amacrine cells, 5 ganglion cells, and 1 centrifugal midbrain neuron. Six of these 15 cell types are ubiquitously distributed, comprising 3 amacrine cells, 2 displaced ganglion cells, and a presumed orthotopic ganglion cell. The remaining nine cell types are regionally restricted within the retina. As previously reported, efferent fibers of midbrain neurons and their postsynaptic partners, the unusual axon-bearing target amacrine cells, are entirely confined to the ventral retina. Also confined to the ventral retina, though with somewhat different distributions, are the "bullwhip" amacrine cells thought to be involved in eye growth, an orthotopic ganglion cell, and two types of large axon-bearing amacrine cells whose dendrites and axons lie in stratum 1 of the inner plexiform layer (IPL). Intracellular fills of these two cell types showed that only a minority of otherwise morphologically indistinguishable neurons are nitrergic. Two amacrine cells that branch throughout the IPL are confined to an equatorial band, and one small-field orthotopic ganglion cell that branches in the proximal IPL is entirely dorsal. These findings suggest that the retina uses different processing on different regions of the visual image, though the benefit of this is presently obscure.
Collapse
|
26
|
Abstract
The refractive errors, myopia and hyperopia, are optical defects of the visual system that can cause blurred vision. Uncorrected refractive errors are the most common causes of visual impairment worldwide. It is estimated that 2.5 billion people will be affected by myopia alone within the next decade. Experimental, epidemiological and clinical research has shown that refractive development is influenced by both environmental and genetic factors. Animal models have showed that eye growth and refractive maturation during infancy are tightly regulated by visually guided mechanisms. Observational data in human populations provide compelling evidence that environmental influences and individual behavioral factors play crucial roles in myopia susceptibility. Nevertheless, the majority of the variance of refractive error within populations is thought to be because of hereditary factors. Genetic linkage studies have mapped two dozen loci, while association studies have implicated more than 25 different genes in refractive variation. Many of these genes are involved in common biological pathways known to mediate extracellular matrix (ECM) composition and regulate connective tissue remodeling. Other associated genomic regions suggest novel mechanisms in the etiology of human myopia, such as mitochondrial-mediated cell death or photoreceptor-mediated visual signal transmission. Taken together, observational and experimental studies have revealed the complex nature of human refractive variation, which likely involves variants in several genes and functional pathways. Multiway interactions between genes and/or environmental factors may also be important in determining individual risks of myopia, and may help explain the complex pattern of refractive error in human populations.
Collapse
Affiliation(s)
- R Wojciechowski
- Statistical Genetics Section, Inherited Disease Branch, National Human Genome Research Institute/NIH, 333 Cassell Drive, Baltimore, MD 21224, USA.
| |
Collapse
|
27
|
Söhl G, Joussen A, Kociok N, Willecke K. Expression of connexin genes in the human retina. BMC Ophthalmol 2010; 10:27. [PMID: 20979653 PMCID: PMC2984586 DOI: 10.1186/1471-2415-10-27] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Accepted: 10/27/2010] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Gap junction channels allow direct metabolically and electrical coupling between adjacent cells in various mammalian tissues. Each channel is composed of 12 protein subunits, termed connexins (Cx). In the mouse retina, Cx43 could be localized mostly between astroglial cells whereas expression of Cx36, Cx45 and Cx57 genes has been detected in different neuronal subtypes. In the human retina, however, the expression pattern of connexin genes is largely unknown. METHODS Northern blot hybridizations, RT-PCR as well as immunofluorescence analyses helped to explore at least partially the expression pattern of the following human connexin genes GJD2 (hCx36), GJC1 (hCx45), GJA9 (hCx59) and GJA10 (hCx62) in the human retina. RESULTS Here we report that Northern blot hybridization signals of the orthologuous hCx36 and hCx45 were found in human retinal RNA. Immunofluorescence signals for both connexins could be located in both inner and outer plexiform layer (IPL, OPL). Expression of a third connexin gene denoted as GJA10 (Cx62) was also detected after Northern blot hybridization in the human retina. Interestingly, its gene structure is similar to that of Gja10 (mCx57) being expressed in mouse horizontal cells. RT-PCR analysis suggested that an additional exon of about 25 kb further downstream, coding for 12 amino acid residues, is spliced to the nearly complete reading frame on exon2 of GJA10 (Cx62). Cx59 mRNA, however, with high sequence identity to zebrafish Cx55.5 was only weakly detectable by RT-PCR in cDNA of human retina. CONCLUSION In contrast to the neuron-expressed connexin genes Gjd2 coding for mCx36, Gjc1 coding for mCx45 and Gja10 coding for mCx57 in the mouse, a subset of 4 connexin genes, including the unique GJA9 (Cx59) and GJA10 (Cx62), could be detected at least as transcript isoforms in the human retina. First immunofluorescence analyses revealed a staining pattern of hCx36 and hCx45 expression both in the IPL and OPL, partially reminiscent to that in the mouse, although additional post-mortem material is needed to further explore their sublamina-specific distribution. Appropriate antibodies against Cx59 and Cx62 protein will clarify expression of these proteins in future studies.
Collapse
Affiliation(s)
- Goran Söhl
- Institut für Genetik der Universität Bonn, Römerstr. 164, 53117 Bonn, Germany
- Martinus Gymnasium Linz, Martinusstraße 1, 53545 Linz am Rhein, Germany
| | - Antonia Joussen
- Zentrum für Augenheilkunde der Universität Köln, Abteilung für Netzhaut und Glaskörperchirurgie, Kerpener Str. 62, 50924 Köln, Germany
- Klinik für Augenheilkunde der Charité - Universitätsmedizin Berlin Campus Benjamin Franklin, Hindenburgdamm 30, 12200 Berlin, Germany
| | - Norbert Kociok
- Zentrum für Augenheilkunde der Universität Köln, Abteilung für Netzhaut und Glaskörperchirurgie, Kerpener Str. 62, 50924 Köln, Germany
- Augenklinik des Universitätsklinikums Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Klaus Willecke
- Institut für Genetik der Universität Bonn, Römerstr. 164, 53117 Bonn, Germany
- LIMES Institut, Universität Bonn, Carl-Troll-Str. 31, 53115 Bonn, Germany
| |
Collapse
|
28
|
Solouki AM, Verhoeven VJM, van Duijn CM, Verkerk AJMH, Ikram MK, Hysi PG, Despriet DDG, van Koolwijk LM, Ho L, Ramdas WD, Czudowska M, Kuijpers RWAM, Amin N, Struchalin M, Aulchenko YS, van Rij G, Riemslag FCC, Young TL, Mackey DA, Spector TD, Gorgels TGMF, Willemse-Assink JJM, Isaacs A, Kramer R, Swagemakers SMA, Bergen AAB, van Oosterhout AALJ, Oostra BA, Rivadeneira F, Uitterlinden AG, Hofman A, de Jong PTVM, Hammond CJ, Vingerling JR, Klaver CCW. A genome-wide association study identifies a susceptibility locus for refractive errors and myopia at 15q14. Nat Genet 2010; 42:897-901. [PMID: 20835239 PMCID: PMC4115149 DOI: 10.1038/ng.663] [Citation(s) in RCA: 157] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Accepted: 08/19/2010] [Indexed: 02/07/2023]
Abstract
Refractive errors are the most common ocular disorders worldwide and may lead to blindness. Although this trait is highly heritable, identification of susceptibility genes has been challenging. We conducted a genome-wide association study for refractive error in 5,328 individuals from a Dutch population-based study with replication in four independent cohorts (combined 10,280 individuals in the replication stage). We identified a significant association at chromosome 15q14 (rs634990, P = 2.21 × 10⁻¹⁴). The odds ratio of myopia compared to hyperopia for the minor allele (minor allele frequency = 0.47) was 1.41 (95% CI 1.16-1.70) for individuals heterozygous for the allele and 1.83 (95% CI 1.42-2.36) for individuals homozygous for the allele. The associated locus is near two genes that are expressed in the retina, GJD2 and ACTC1, and appears to harbor regulatory elements which may influence transcription of these genes. Our data suggest that common variants at 15q14 influence susceptibility for refractive errors in the general population.
Collapse
Affiliation(s)
- Abbas M Solouki
- Department of Ophthalmology, Erasmus Medical Center, Rotterdam, The Netherlands
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Photoreceptor coupling is controlled by connexin 35 phosphorylation in zebrafish retina. J Neurosci 2009; 29:15178-86. [PMID: 19955370 DOI: 10.1523/jneurosci.3517-09.2009] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Electrical coupling of neurons is widespread throughout the CNS and is observed among retinal photoreceptors from essentially all vertebrates. Coupling dampens voltage noise in photoreceptors and rod-cone coupling provides a means for rod signals to enter the cone pathway, extending the dynamic range of rod-mediated vision. This coupling is dynamically regulated by a circadian rhythm and light adaptation. We examined the molecular mechanism that controls photoreceptor coupling in zebrafish retina. Connexin 35 (homologous to Cx36 of mammals) was found at both cone-cone and rod-cone gap junctions. Photoreceptors showed strong Neurobiotin tracer coupling at night, extensively labeling the network of cones. Tracer coupling was significantly reduced in the daytime, showing a 20-fold lower diffusion coefficient for Neurobiotin transfer. The phosphorylation state of Cx35 at two regulatory phosphorylation sites, Ser110 and Ser276, was directly related to tracer coupling. Phosphorylation was high at night and low during the day. Protein kinase A (PKA) activity directly controlled both phosphorylation state and tracer coupling. Both were significantly increased in the day by pharmacological activation of PKA and significantly reduced at night by inhibition of PKA. The data are consistent with direct phosphorylation of Cx35 by PKA. We conclude that the magnitude of photoreceptor coupling is controlled by the dynamic phosphorylation and dephosphorylation of Cx35. Furthermore, the nighttime state is characterized by extensive coupling that results in a well connected cone network.
Collapse
|
30
|
Kihara AH, Santos TO, Osuna-Melo EJ, Paschon V, Vidal KSM, Akamine PS, Castro LM, Resende RR, Hamassaki DE, Britto LRG. Connexin-mediated communication controls cell proliferation and is essential in retinal histogenesis. Int J Dev Neurosci 2009; 28:39-52. [PMID: 19800961 DOI: 10.1016/j.ijdevneu.2009.09.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 09/09/2009] [Accepted: 09/24/2009] [Indexed: 12/29/2022] Open
Abstract
Connexin (Cx) channels and hemichannels are involved in essential processes during nervous system development such as apoptosis, propagation of spontaneous activity and interkinetic nuclear movement. In the first part of this study, we extensively characterized Cx gene and protein expression during retinal histogenesis. We observed distinct spatio-temporal patterns among studied Cx and an overriding, ubiquitous presence of Cx45 in progenitor cells. The role of Cx-mediated communication was assessed by using broad-spectrum (carbenoxolone, CBX) and Cx36/Cx50 channel-specific (quinine) blockers. In vivo application of CBX, but not quinine, caused remarkable reduction in retinal thickness, suggesting changes in cell proliferation/apoptosis ratio. Indeed, we observed a decreased number of mitotic cells in CBX-injected retinas, with no significant changes in the expression of PCNA, a marker for cells in proliferative state. Taken together, our results pointed a pivotal role of Cx45 in the developing retina. Moreover, this study revealed that Cx-mediated communication is essential in retinal histogenesis, particularly in the control of cell proliferation.
Collapse
Affiliation(s)
- Alexandre H Kihara
- Núcleo de Cognição e Sistemas Complexos, Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, Santo André, SP, Brazil.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Cook JE, Becker DL. Gap-Junction Proteins in Retinal Development: New Roles for the “Nexus”. Physiology (Bethesda) 2009; 24:219-30. [DOI: 10.1152/physiol.00007.2009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Gap-junction channels, the cytoplasmic proteins that associate with them, and the transcriptional networks that regulate them are increasingly being viewed as critical communications hubs for cell signaling in health and disease. As a result, the term “nexus,” which was the original structural name for these focal intercellular links, is coming back into use with new proteomic and transcriptomic meanings. The retina is better understood than any other part of the vertebrate central nervous system in respect of its developmental patterning, its diverse neuronal types and circuits, and the emergence of its definitive structure-function correlations. Thus, studies of the junctional and nonjunctional nexus roles of gap-junction proteins in coordinating retinal development should throw useful light on cell signaling in other developing nervous tissues.
Collapse
Affiliation(s)
- Jeremy E. Cook
- Department of Cell and Developmental Biology, University College London, Gower Street, London, United Kingdom
| | - David L. Becker
- Department of Cell and Developmental Biology, University College London, Gower Street, London, United Kingdom
| |
Collapse
|