Article
Multidisciplinary Sciences
Jianmin Su, Ubadah Sabbagh, Yanping Liang, Lucie Olejnikova, Karen G. Dixon, Ashley L. Russell, Jiang Chen, Yuchin Albert Pan, Jason W. Triplett, Michael A. Fox
Summary: The molecular mechanisms directing the precise laminar targeting of ipsilateral-projecting RGC axons to the deep sublamina of SC have been identified to involve the extracellular glycoprotein NPNT and integrin receptors, providing the assembly of eye-specific parallel visual pathways.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Multidisciplinary Sciences
Jennings C. Luu, Aicha Saadane, Henri Leinonen, Elliot H. Choi, Fangyuan Gao, Dominik Lewandowski, Maximilian Halabi, Christopher L. Sander, Arum Wu, Jacob M. Wang, Rupesh Singh, Songqi Gao, Emma M. Lessieur, Zhiqian Dong, Grazyna Palczewska, Robert F. Mullins, Neal S. Peachey, Philip D. Kiser, Marcin Tabaka, Timothy S. Kern, Krzysztof Palczewski
Summary: Chronic, progressive retinal diseases result from disruptions in cellular and tissue homeostasis, leading to vision impairment and blindness. Existing therapeutic options are limited for these diseases, especially in the early stages. A systems pharmacology approach was used to identify molecular mechanisms and develop targeted pharmacological inhibition of cyclic nucleotide phosphodiesterases (PDEs), resulting in enhanced resilience and preservation of retinal structure and function. This approach shows promise for the treatment and prevention of common causes of blindness.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Biochemistry & Molecular Biology
Lauren L. Daniele, John Y. S. Han, Ivy S. Samuels, Ravikiran Komirisetty, Nikhil Mehta, Jessica L. McCord, Minzhong Yu, Yekai Wang, Kathleen Boesze-Battaglia, Brent A. Bell, Jianhai Du, Neal S. Peachey, Nancy J. Philp
Summary: Glucose supply is crucial for the normal functioning and survival of retinal cells. This study demonstrates the essential role of glucose in maintaining and sustaining rod photoreceptor outer segments (OS), with minimal impact on cone photoreceptor cells.
Article
Biology
Tylor R. Lewis, Sebastien Phan, Carson M. Castillo, Keun-Young Kim, Kelsey Coppenrath, William Thomas, Ying Hao, Nikolai P. Skiba, Marko E. Horb, Mark H. Ellisman, Vadim Y. Arshavsky, Audrey M. Bernstein
Summary: The initial steps of vision occur in stacked membrane structures called discs located within the outer segment compartment of photoreceptor cells. These discs become enclosed and form deep indentations known as incisures. Using electron microscopy and tomography, it was discovered that incisures only form after complete disc enclosure. The size of the incisures is determined by the ratio of peripherin-2 to rhodopsin, with a higher ratio resulting in larger and more complex incisures.
Article
Cell Biology
Tian Wang, Yiming Li, Miao Guo, Xue Dong, Mengyu Liao, Mei Du, Xiaohong Wang, Haifang Yin, Hua Yan
Summary: Traumatic optic neuropathy (TON) is characterized by optic nerve damage resulting in vision loss, with limited treatment options. Pituitary adenylate cyclase-activating polypeptide 38 (PACAP38) has shown promise as a therapeutic agent. Using rat retinal ganglion cell (RGC) exosomes as delivery vesicles for PACAP38 (EXOPACAP38) demonstrated improved uptake efficiency and potential for promoting RGC survival, nerve fiber layer thickness, axon regeneration, and optic nerve function in a rat TON model. EXOPACAP38 may offer therapeutic implications for TON patients.
FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY
(2021)
Article
Cell Biology
Karine Parain, Sophie Lourdel, Alicia Donval, Albert Chesneau, Caroline Borday, Odile Bronchain, Morgane Locker, Muriel Perron
Summary: This study developed rhodopsin gene editing-based models of retinitis pigmentosa using CRISPR/Cas9 technology in two species of frogs. The results showed divergent responses of Muller glial cells to retinal injury in closely related Xenopus laevis and Xenopus tropicalis.
Article
Biochemistry & Molecular Biology
German Michelis, Olga Lorena German, Rafael Villasmil, Tamara Soto, Nora P. Rotstein, Luis Politi, S. Patricia Becerra
Summary: The study demonstrates the neurotrophic effects of PEDF on cultured retinal neurons, showing its ability to protect photoreceptor cells from apoptosis, promote cell development, and induce neurite outgrowth in amacrine neurons. These effects are specifically mediated by short peptide fragments derived from the neurotrophic domain of PEDF, suggesting their potential as neuronal guardians for the retina.
JOURNAL OF NEUROCHEMISTRY
(2021)
Article
Neurosciences
Lena Nemitz, Karin Dedek, Ulrike Janssen-Bienhold
Summary: Early postnatal ablation of horizontal cells in the mouse retina leads to differential remodeling in the cone pathway, where new synapses are established between cones and OFF bipolar cells while connections with ON bipolar cells are lost.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2021)
Article
Biochemistry & Molecular Biology
Matthew J. Van Hook
Summary: Glaucoma is an age-related neurodegenerative disorder associated with sensitivity to intraocular pressure. It is the leading cause of irreversible vision loss worldwide, resulting from damage to the retinal ganglion cells. Glaucoma affects different populations of these cells to varying extents and along distinct time courses, and its effects on synaptic function and vulnerability of the cells are still not fully understood. Further research is needed to determine the underlying mechanisms and to develop diagnostic and therapeutic approaches.
ANTIOXIDANTS & REDOX SIGNALING
(2022)
Article
Cell Biology
Tylor R. Lewis, Sebastien Phan, Keun-Young Kim, Isha Jha, Carson M. Castillo, Jin-Dong Ding, Benjamin S. Sajdak, Dana K. Merriman, Mark H. Ellisman, Vadim Y. Arshavsky
Summary: This study reveals that healthy mammalian photoreceptor cells release microvesicles, some of which contain visual pigment rhodopsin. This release may be enhanced under pathological conditions associated with defects in protein targeting and trafficking.
DISEASE MODELS & MECHANISMS
(2022)
Article
Neurosciences
Jian Hao Liu, Jeet Bahadur Singh, Margaret Lin Veruki, Espen Hartveit
Summary: AII amacrine cells in mammalian retinas exhibit a unique process resembling an axon initial segment, with the ability to generate action potentials, which may be related to extrasynaptic neurotransmission.
JOURNAL OF COMPARATIVE NEUROLOGY
(2021)
Article
Neurosciences
Abhishek Chadha, Antonio E. Paniagua, David S. Williams
Summary: This study investigated the localization of GPCRs in different types of cilia, finding that SSTR3 was specifically localized to all types of cilia, while RHO showed a preference for photoreceptor cilia. A novel CLS in the SSTR3 C terminus was identified as crucial for ciliary localization, and adding this CLS to other proteins also enabled ciliary localization. Deletion of the C terminus of RHO in mouse retinas reduced its localization in rod outer segments, but addition of the SSTR3 C-terminal CLS partially rescued this mislocalization. Overall, distinct C-terminal elements of SSTR3 and RHO play key roles in determining specificity of cilium localization among different types of cilia.
JOURNAL OF NEUROSCIENCE
(2021)
Article
Ophthalmology
James R. Tribble, Amin Otmani, Eirini Kokkali, Emma Lardner, James E. Morgan, Pete A. Williams
Summary: An inducible, magnetic bead model in Brown Norway rats was developed to replicate glaucoma features in human eyes. The model successfully demonstrated degeneration across multiple retinal ganglion cell compartments, providing a platform for testing glaucoma therapeutics.
TRANSLATIONAL VISION SCIENCE & TECHNOLOGY
(2021)
Article
Neurosciences
Lydia M. Mathger, Kevin Zhao, Lena Herbst
Summary: Research on retinal specializations in skates revealed uneven distribution of photoreceptors, with a horizontally located visual streak showing higher density. Photoreceptors varied in length and thickness at different locations, and displayed tilting within the eye. These findings provide insights into the animal's anatomy, lifestyle, and habitat types.
JOURNAL OF COMPARATIVE NEUROLOGY
(2021)
Article
Cell Biology
Ashish K. Solanki, Manas R. Biswal, Stephen Walterhouse, Rene Martin, Altaf A. Kondkar, Hans-Joachim Knolker, Bushra Rahman, Ehtesham Arif, Shahid Husain, Sandra R. Montezuma, Deepak Nihalani, Glenn Prazere Lobo
Summary: The unconventional myosin MYO1C plays a crucial role in rhodopsin localization to photoreceptor outer segments and is essential for normal visual function. Loss of MYO1C in mice leads to rhodopsin mislocalization, impaired photoreceptor function, and progressively shorter outer segments, indicating its significance in retinal cell physiology.
Article
Behavioral Sciences
Petra Bolte, Angelika Einwich, Pranav K. Seth, Raisa Chetverikova, Dominik Heyers, Irina Wojahn, Ulrike Janssen-Bienhold, Regina Feederle, Peter Hore, Karin Dedek, Henrik Mouritsen
Summary: The magnetic compass of birds is based on light-dependent radical-pair processes in the eyes, with cryptochromes being the primary candidate proteins for magnetoreceptor molecules. A study on various bird species confirmed the localization of Cry1a in the UV/V cone outer segments, suggesting accumulation of Cry1a molecules in distinct spots. No significant difference in Cry1a immunoreactivity was observed between light- and dark-adapted retinae, indicating that a C-terminal antibody against Cry1a does not specifically label a light-activated form of the protein.
ETHOLOGY ECOLOGY & EVOLUTION
(2021)
Article
Ophthalmology
Felix Friedrich Reichel, Stylianos Michalakis, Barbara Wilhelm, Ditta Zobor, Regine Muehlfriedel, Susanne Kohl, Nicole Weisschuh, Vithiyanjali Sothilingam, Laura Kuehlewein, Nadine Kahle, Immanuel Seitz, Francois Paquet-Durand, Stephen H. Tsang, Peter Martus, Tobias Peters, Mathias Seeliger, Karl Ulrich Bartz-Schmidt, Marius Ueffing, Eberhard Zrenner, Martin Biel, Bernd Wissinger, Dominik Fischer
Summary: The study found that the subretinal gene therapy for CNGA3-associated achromatopsia demonstrated a very good safety profile even at the highest dose administered. Functional benefits were noted in the treated eye and persisted throughout the follow-up period, but further research with larger sample sizes is needed to determine efficacy. The trial results will inform future clinical trials on the design and endpoints, with a potential focus on treating younger patients to avoid amblyopia as a limiting factor.
BRITISH JOURNAL OF OPHTHALMOLOGY
(2022)
Article
Neurosciences
Silke Haverkamp, Laszlo Albert, Vaishnavi Balaji, Pavel Nemec, Karin Dedek
Summary: In this study, various transcription factors were tested in two avian species, revealing their crucial role in the ganglion cells of birds. The markers established may serve as valuable tools for further detailed studies on the retinal circuitry of these highly visual animals.
JOURNAL OF COMPARATIVE NEUROLOGY
(2021)
Article
Neurosciences
Anja Guenther, Karin Dedek, Silke Haverkamp, Stephan Irsen, Kevin L. Briggman, Henrik Mouritsen
Summary: Research has found that double cones in avian retinas are highly interconnected with neighboring double cones and other photoreceptor cells through telodendria-to-terminal and telodendria-to-telodendria contacts. Additionally, 15 bipolar cell types have been identified in the chicken retina based on different criteria such as axonal stratifications, photoreceptor contact patterns, soma position, and dendritic and axonal field mosaics. This study reveals a more complex connectivity network in the outer plexiform layer of the avian retina than previously thought.
JOURNAL OF NEUROSCIENCE
(2021)
Article
Physics, Condensed Matter
Timo Grothe, Tobias Boehm, Karim Habashy, Oliya S. Abdullaeva, Jennifer Zablocki, Arne Luetzen, Karin Dedek, Manuela Schiek, Andrea Ehrmann
Summary: Recent advances in optoelectronics are often based on thin-film organic semiconductors, such as squaraines, which show excitonic coupling with visible light. Coating squaraine films on electrospun nanofiber mats and nanomembranes made conductive by PEDOT:PSS can significantly alter the thin film formation and improve optical properties.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2021)
Article
Neurosciences
Lena Nemitz, Karin Dedek, Ulrike Janssen-Bienhold
Summary: Early postnatal ablation of horizontal cells in the mouse retina leads to differential remodeling in the cone pathway, where new synapses are established between cones and OFF bipolar cells while connections with ON bipolar cells are lost.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2021)
Article
Biochemistry & Molecular Biology
Christian Behrens, Shubhash Chandra Yadav, Maria M. Korympidou, Yue Zhang, Silke Haverkamp, Stephan Irsen, Anna Schaedler, Xiaoyu Lu, Zhuohe Liu, Jan Lause, Francois St-Pierre, Katrin Franke, Anna Vlasits, Karin Dedek, Robert G. Smith, Thomas Euler, Philipp Berens, Timm Schubert
Summary: The study revealed the existence of two synaptic strata in the outer plexiform layer of the mouse retina, where horizontal cells provide global signaling to CBCs through bulbs and local, cone-specific feedback to cones through dendritic tips. This spatial arrangement of synaptic contacts allows for simultaneous different modes of signaling by horizontal cells.
Article
Behavioral Sciences
Angelika Einwich, Pranav Kumar Seth, Rabea Bartoelke, Petra Bolte, Regina Feederle, Karin Dedek, Henrik Mouritsen
Summary: Research has shown that Cry2 protein is located in different layers of cells in the retina of night-migratory European robins, homing pigeons, and domestic chickens, and at a subcellular level, it is present in both the cytoplasm and the nucleus of these cells.
JOURNAL OF COMPARATIVE PHYSIOLOGY A-NEUROETHOLOGY SENSORY NEURAL AND BEHAVIORAL PHYSIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Jie Yan, Alexander Guenter, Soumyaparna Das, Regine Muehlfriedel, Stylianos Michalakis, Kangwei Jiao, Mathias W. Seeliger, Francois Paquet-Durand
Summary: Inherited retinal degenerations (IRDs) are blinding diseases characterized by progressive loss of photoreceptors. The excessive activation of calpain and poly (ADP-ribose) polymerase (PARP) is associated with the pathology of IRDs. Inhibitors of these enzymes have shown promise in preventing photoreceptor cell death. However, the relationship between calpain and PARP in IRDs is still unclear. In this study, organotypic retinal explant cultures were used to investigate the effects of calpain inhibitors, PARP inhibitors, and voltage-gated Ca2+ channel (VGCC) inhibitors on cell death in IRD mice models. The results suggest that PARP acts upstream of calpain and both enzymes are part of the same degenerative pathway in Pde6b-dependent photoreceptor degeneration. Our findings highlight the potential of targeting PARP for therapeutic interventions in IRD-type diseases.
Article
Cardiac & Cardiovascular Systems
Michael M. Orlich, Rodrigo Dieguez-Hurtado, Regine Muehlfriedel, Vithiyanjali Sothilingam, Hartwig Wolburg, Cansu Ebru Oender, Pascal Woelffing, Christer Betsholtz, Konstantin Gaengel, Mathias Seeliger, Ralf H. Adams, Alfred Nordheim
Summary: This study reveals the crucial role of the transcription factor SRF in pericytes and vascular smooth muscle cells, which is essential for maintaining vascular integrity and tone.
CIRCULATION RESEARCH
(2022)
Editorial Material
Neurosciences
Tamas Kovacs-Oller, Karin Dedek, Daniel Hillier
FRONTIERS IN CELLULAR NEUROSCIENCE
(2022)
Article
Neurosciences
Vaishnavi Balaji, Silke Haverkamp, Pranav Kumar Seth, Anja Guenther, Ezequiel Mendoza, Jessica Schmidt, Maike Herrmann, Leonie Lovis Pfeiffer, Pavel Nemec, Constance Scharff, Henrik Mouritsen, Karin Dedek
Summary: Visual signal processing starts at the first synapse, where different types of bipolar cells receive information from photoreceptors and feed it into different processing channels. This study systematically tested 12 antibodies for their ability to label individual bipolar cells in the bird retina and identified 8 suitable antibodies across different bird species and retinal regions. The catalog of bipolar cell markers provided in this study will greatly facilitate the analysis of retinal circuitry in birds on a larger scale.
JOURNAL OF COMPARATIVE NEUROLOGY
(2023)
Article
Multidisciplinary Sciences
Raisa Chetverikova, Glen Dautaj, Leonard Schwigon, Karin Dedek, Henrik Mouritsen
Summary: Through studying the retinas of European robins and domestic chickens, it has been found that their double cone photoreceptors are highly ordered, which may aid their function in light-dependent magnetoreception and/or polarized light sensing.
JOURNAL OF THE ROYAL SOCIETY INTERFACE
(2022)
Meeting Abstract
Biotechnology & Applied Microbiology
Lisa M. Riedmayr, Klara S. Hinrichsmeyer, Sybille Boehm, Victoria Splith, Stylianos Michalakis, Martin Biel, Elvir Becirovic
Meeting Abstract
Pharmacology & Pharmacy
V. Tsvilovskyy, U. Kriebs, A. Bach, A. Jha, A. Wirth, C. Grimm, U. Wissenbach, K. Zimmermann, P. Weissgerber, D. Vogt, D. Schumacher, J. Camacho Londono, C. Wahl-Schott, A. Pfeifer, M. Biel, P. Lipp, V. Flockerzi, S. Muallem, M. Freichel
NAUNYN-SCHMIEDEBERGS ARCHIVES OF PHARMACOLOGY
(2020)