Article
Ophthalmology
Adam Davison, Kaspar Gierke, Johann Helmut Brandstaetter, Norbert Babai
Summary: This study investigated the functional and structural maturation of mouse cone photoreceptor ribbon synapses during postnatal development, as well as the role of synaptic ribbons in synaptic vesicle release. The presence of synaptic ribbons attenuated tonic synaptic vesicle release and amplified multiquantal release, but spontaneous release may not depend on synaptic ribbons or voltage-sensitive calcium channels.
INVESTIGATIVE OPHTHALMOLOGY & VISUAL SCIENCE
(2022)
Article
Biochemistry & Molecular Biology
Shweta Suiwal, Mayur Dembla, Karin Schwarz, Rashmi Katiyar, Martin Jung, Yvonne Carius, Stephan Maxeiner, Marcel A. Lauterbach, C. Roy D. Lancaster, Frank Schmitz
Summary: Unc119 protein mediates transport of myristoylated proteins to the photoreceptor outer segment and is also enriched in photoreceptor synapses. The synaptic ribbon could be involved in the discharge of Unc119-bound lipid-modified proteins. Proteins associated with Unc119 may play important roles in photoreceptor synapses.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Review
Physiology
Wallace B. Thoreson
Summary: The review explores the conversion of light-evoked voltage responses of rod and cone photoreceptor cells in the vertebrate retina to synaptic vesicle release events for transmission to downstream neurons. It discusses processes, proteins, and structures involved in this early step in vision, focusing on studies from salamander retina with comparisons to other experimental animals. Many mechanisms are conserved across species, highlighting the importance of understanding the intricate details of synaptic transmission in the visual system.
PFLUGERS ARCHIV-EUROPEAN JOURNAL OF PHYSIOLOGY
(2021)
Article
Neurosciences
Adam Davison, Kaspar Gierke, Johann Helmut Brandstaetter, Norbert Babai
Summary: By studying the maturation process of synaptic ribbons in cone photoreceptors, it was found that ribbon attachment increases the density of synaptic vesicles, increases the pool size of readily releasable vesicles, and enhances the calcium sensitivity of glutamate release.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2022)
Article
Physiology
Norbert Babai, Julia von Wittgenstein, Kaspar Gierke, Johann Helmut Brandstaetter, Andreas Feigenspan
Summary: The study showed that impaired ribbon synapses significantly reduce signal transmission, including vesicle replenishment rates and the size of the readily releasable pool. The mutant Off cone bipolar cells exhibited a change in their response to light offset.
Article
Biochemistry & Molecular Biology
Akari Hagiwara, Ayako Mizutani, Saki Kawamura, Manabu Abe, Yamato Hida, Kenji Sakimura, Toshihisa Ohtsuka
Summary: This study investigates the roles of CAST and ELKS in ectopic synapse localization. The depletion of CAST and ELKS in the retina leads to degeneration of photoreceptors, indicating their critical roles in maintaining neural signal transduction in the retina. However, the distribution of the photoreceptor triad synapse is not solely dependent on their actions within photoreceptors and horizontal cells.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Neurosciences
Ji-Jie Pang, Fan Gao, Samuel M. Wu
Summary: The study examined signal transmission at the glutamatergic synapse between rod photoreceptors and their postsynaptic hyperpolarizing bipolar cells, finding that scotopic light can induce graded potentials in rods and the depolarizing phase associated with light offset can trigger action potentials lasting 241.8 ms.
FRONTIERS IN CELLULAR NEUROSCIENCE
(2021)
Article
Neurosciences
Annia Abtout, Gordon Fain, Jurgen Reingruber
Summary: This study analyzed the contribution of various biological processes in the photoreceptor light response, finding that the shape of the response is controlled by deactivation parameters, while activation parameters scale the shape and affect the amplitude. The rising phase of the response is shown to depend on Ca2+ feedback, contrary to previous belief. New methods were devised to extract activation and deactivation rates from the analysis of response shape and amplitude.
JOURNAL OF PHYSIOLOGY-LONDON
(2021)
Article
Biology
Rikard Frederiksen, Gordon L. Fain, Alapakkam P. Sampath
Summary: A study found that lamprey, like mammals, have rod bipolar cells that primarily receive input from rod photoreceptors. These cells have a unique morphology and spectral sensitivity similar to rod photoreceptors. This discovery suggests that early vertebrates may have had a more diverse retinal organization than previously thought.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2022)
Review
Neurosciences
Trevor D. Lamb
Summary: The vertebrate retina utilizes a duplex system of photoreceptors, rods and cones, to detect light under different levels of illumination. Rods are more sensitive but slower in response, functioning effectively in low light, while cones respond rapidly and work in brighter conditions. These two types of cells use different genes for the process of light detection, representing a unique evolutionary system.
JOURNAL OF PHYSIOLOGY-LONDON
(2022)
Review
Medicine, General & Internal
Alexandra V. Garafalo, Rebecca Sheplock, Alexander Sumaroka, Alejandro J. Roman, Artur V. Cideciyan, Samuel G. Jacobson
Summary: Inherited retinal diseases (IRDs) encompass cone-rod diseases, which have complex etiologies and can lead to vision loss. Among the causative genes, there is diversity, leading to a variety of disease manifestations, and paving the way for potential therapies.
Article
Cell Biology
David Jimeno, Concepcion Lillo, Pedro de la Villa, Nuria Calzada, Eugenio Santos, Alberto Fernandez-Medarde
Summary: The study reveals that GRF2 and CDC42 play key roles in regulating nuclear positioning and survival of retinal cone photoreceptor cells, while RAC1 does not have a significant effect. These findings support the notion that loss-of-function mutations in GRF2 may be potential drivers of cone retinal dystrophies.
Article
Cell Biology
Alina Dittrich, Girish Ramesh, Martin Jung, Frank Schmitz
Summary: This study demonstrates the localization of rabconnectin-3a (RC3a), also known as Dmx-like 2 (DMXL2), to the synaptic ribbons of rod photoreceptor synapses in the mouse retina, suggesting its role in ensuring reliable synaptic communication.
Article
Neurosciences
Annette E. Allen
Summary: This study investigates how the circadian clock regulates rod and cone vision under intermediate light conditions. The researchers found that the visual responses of rods and cones vary with time and light intensity. The circadian clock plays a crucial role in regulating rod/cone vision across the mesopic transition.
JOURNAL OF NEUROSCIENCE
(2022)
Article
Neurosciences
Ben James, Pawel Piekarz, Jose Moya-Diaz, Leon Lagnado
Summary: This study demonstrates how presynaptic integration of vesicles by MVR can increase the efficiency with which sensory information is transmitted compared with a rate-code described by Poisson statistics.
JOURNAL OF NEUROSCIENCE
(2022)