The Localization of the Site of ArylalkylamineN-Acetyltransferase Circadian Expression in the Photoreceptor Cells of Mammalian Retina

1998 ◽  
Vol 248 (1) ◽  
pp. 115-120 ◽  
Author(s):  
Tomoko Niki ◽  
Toshiyuki Hamada ◽  
Michiko Ohtomi ◽  
Katsuhiko Sakamoto ◽  
Satoru Suzuki ◽  
...  
Keyword(s):  
Photoreceptor Cells ◽  
Circadian Expression ◽  
Mammalian Retina

The Localization of the Site of Arylalkylamine N-Acetyltransferase Circadian Expression in the Photoreceptor Cells of Mammalian Retina

1999 ◽  
Vol 261 (2) ◽  
pp. 546
Author(s):  
Tomoko Niki ◽  
Toshiyuki Hamada ◽  
Michiko Ohtomi ◽  
Katsuhiko Sakamoto ◽  
Satoru Suzuki ◽  
...  
Keyword(s):  
Photoreceptor Cells ◽  
Circadian Expression ◽  
Mammalian Retina

Special characteristics of the transcription and splicing machinery in photoreceptor cells of the mammalian retina

2015 ◽  
Vol 362 (2) ◽  
pp. 281-294 ◽  
Author(s):  
Kristin Derlig ◽  
Andreas Gießl ◽  
Johann Helmut Brandstätter ◽  
Ralf Enz ◽  
Regina Dahlhaus
Keyword(s):  
Photoreceptor Cells ◽  
Mammalian Retina ◽  
Splicing Machinery

Sequence of Changes in the Fine Structure of the Retina of Dogs Irradiated During Retinal Maturation

1967 ◽  
Vol 25 ◽  
pp. 166-167
Author(s):  
James N. Shively ◽  
Robert D. Phemister ◽  
Glenwood P. Epling
Keyword(s):  
Fine Structure ◽  
Ionizing Radiation ◽  
Photoreceptor Cells ◽  
Rosette Formation ◽  
Severe Dysplasia ◽  
Outer Segments ◽  
Mammalian Retina ◽  
Retinal Dysplasia

It has been known since early in this century that exposure to ionizing radiation during maturation of the mammalian retina results in necrosis of post-mitotic differentiating cells in the nuclear layer, followed by marked retinal dysplasia with rosette formation, and partial to complete agenesis of outer segments of photoreceptor cells. The effect has been morphologically related to the area of the retina undergoing differentiation at the time of irradiation. Alteration in spacial and pressure relationships are said to result in the tubular rosette formations. These effects have been described in mice, rats, monkeys, dogs and man. Doses less than 25 R have produced severe dysplasia in the developing retina of mice. The mature retina is damaged only by doses of several hundred to a few thousand R.

scholarly journals Cis-Regulatory Accessibility Directs Muller Glial Development and Regenerative Capacity

2019 ◽  
Author(s):  
Leah S. VandenBosch ◽  
Stefanie G. Wohl ◽  
Matthew S. Wilken ◽  
Kristen Cox ◽  
Laura Chipman ◽  
...  
Keyword(s):  
Adult Mouse ◽  
Expression Profiles ◽  
Photoreceptor Cells ◽  
Bipolar Cells ◽  
Rna Seq ◽  
Retinal Neurons ◽  
Regulatory Motifs ◽  
Glial Development ◽  
Mammalian Retina ◽  
Intermediate Expression

AbstractDiseases and damage to the retina lead to losses in retinal neurons and eventual visual impairment. Although the mammalian retina has no inherent regenerative capabilities, fish have robust regeneration from Müller glia (MG). Recently, we have shown that driving expression of Ascl1 in adult mouse MG stimulates neurogenesis similar to fish regeneration. The regeneration observed in the mouse is limited in the variety of neurons that can be derived from MG; Ascl1-expressing MG primarily generate bipolar cells. To better understand the limits of MG-based regeneration in mouse retinas, we used ATAC- and RNA-seq to compare newborn progenitors with MG. Our analysis demonstrated striking similarities between MG and progenitors, with losses in regulatory motifs for neurogenesis genes. Young MG were found to have intermediate expression profiles and accessible DNA, which is mirrored in the ability of Ascl1 to direct bipolar neurogenesis in young MG. When comparing what makes bipolar and photoreceptor cells distinct from glial cells, we find that bipolar-specific accessible regions are more frequently linked to bHLH motifs and Ascl1 binding, indicating that Ascl1 preferentially binds to bipolar regions. Overall, our analysis indicates a loss of neurogenic gene expression and motif accessibility during glial maturation that may prevent efficient reprogramming.

2106 Circadian expression rhythm of serotonin N-acetyltransferase gene in the mammalian retina

1997 ◽  
Vol 28 ◽  
pp. S245
Author(s):  
Katsuhiko Sakamoto ◽  
Tomoko Niki ◽  
Satoru Suzuki ◽  
Toshiyuki Hamada ◽  
Kazumasa Horikawa ◽  
...  
Keyword(s):  
Circadian Expression ◽  
Mammalian Retina

scholarly journals Substituting mouse transcription factor Pou4f2 with a sea urchin orthologue restores retinal ganglion cell development

2016 ◽  
Vol 283 (1826) ◽  
pp. 20152978 ◽  
Author(s):  
Chai-An Mao ◽  
Cavit Agca ◽  
Julie A. Mocko-Strand ◽  
Jing Wang ◽  
Esther Ullrich-Lüter ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Sea Urchin ◽  
Ganglion Cells ◽  
Sea Urchins ◽  
Photoreceptor Cells ◽  
Retinal Ganglion ◽  
Mammalian Retina ◽  
Morphological Differences ◽  
And Function ◽  
Tube Feet

Pou domain transcription factor Pou4f2 is essential for the development of retinal ganglion cells (RGCs) in the vertebrate retina. A distant orthologue of Pou4f2 exists in the genome of the sea urchin (class Echinoidea) Strongylocentrotus purpuratus ( SpPou4f1/2 ), yet the photosensory structure of sea urchins is strikingly different from that of the mammalian retina. Sea urchins have no obvious eyes, but have photoreceptors clustered around their tube feet disc. The mechanisms that are associated with the development and function of photoreception in sea urchins are largely unexplored. As an initial approach to better understand the sea urchin photosensory structure and relate it to the mammalian retina, we asked whether SpPou4f1/2 could support RGC development in the absence of Pou4f2 . To answer this question, we replaced genomic Pou4f2 with an SpPou4f1/2 cDNA. In Pou4f2 -null mice, retinas expressing SpPou4f1/2 were outwardly identical to those of wild-type mice. SpPou4f1/2 retinas exhibited dark-adapted electroretinogram scotopic threshold responses, indicating functionally active RGCs. During retinal development, SpPou4f1/2 activated RGC-specific genes and in S. purpuratus , SpPou4f2 was expressed in photoreceptor cells of tube feet in a pattern distinct from Opsin4 and Pax6. Our results suggest that SpPou4f1/2 and Pou4f2 share conserved components of a gene network for photosensory development and they maintain their conserved intrinsic functions despite vast morphological differences in mouse and sea urchin photosensory structures.

Spindle shaped bodies in foveolar cones of the baboon retina

1989 ◽  
Vol 47 ◽  
pp. 960-961
Author(s):  
W. Krebs ◽  
I. Krebs
Keyword(s):  
Cross Sections ◽  
Inclusion Bodies ◽  
Photoreceptor Cells ◽  
Papio Anubis ◽  
Retinal Photoreceptor ◽  
Age Related ◽  
Cone Cells ◽  
Membrane Bound ◽  
Oriented Parallel ◽  
Shaped Inclusion

Various inclusion bodies occur in vertebrate retinal photoreceptor cells. Most of them are membrane bound and associated with phagocytosis or they are age related residual bodies. We found an additional inclusion body in foveal cone cells of the baboon (Papio anubis) retina.The eyes of a 15 year old baboon were fixed by immersion in cacodylate buffered glutaraldehyde (2%)/formaldehyde (2%) as described in detail elsewhere . Pieces of retina from various locations, including the fovea, were embedded in epoxy resin such that radial or tangential sections could be cut.Spindle shaped inclusion bodies were found in the cytoplasm of only foveal cones. They were abundant in the inner segments, close to the external limiting membrane (Fig. 1). But they also occurred in the outer fibers, the perikarya, and the inner fibers (Henle’s fibers) of the cone cells. The bodies were between 0.5 and 2 μm long. Their central diameter was 0.2 to 0. 3 μm. They always were oriented parallel to the long axis of the cone cells. In longitudinal sections (Figs. 2,3) they seemed to have a fibrous skeleton that, in cross sections, turned out to consist of plate-like (Fig.4) and tubular profiles (Fig. 5).

Differentiation Processes of the Ocellar Retina of the Honeybee (Apis Mellifera L.)

1990 ◽  
Vol 48 (3) ◽  
pp. 430-431
Author(s):  
Maria Anna Pabst
Keyword(s):  
Apis Mellifera ◽  
Distal Part ◽  
Cell Layer ◽  
Single Layer ◽  
Photoreceptor Cells ◽  
Distal Segment ◽  
Compound Eyes ◽  
Thin Sections ◽  
Ultrastructural Studies ◽  
Adult Worker

In addition to the compound eyes, honeybees have three dorsal ocelli on the vertex of the head. Each ocellus has about 800 elongated photoreceptor cells. They are paired and the distal segment of each pair bears densely packed microvilli forming together a platelike fused rhabdom. Beneath a common cuticular lens a single layer of corneagenous cells is present.Ultrastructural studies were made of the retina of praepupae, different pupal stages and adult worker bees by thin sections and freeze-etch preparations. In praepupae the ocellar anlage consists of a conical group of epidermal cells that differentiate to photoreceptor cells, glial cells and corneagenous cells. Some photoreceptor cells are already paired and show disarrayed microvilli with circularly ordered filaments inside. In ocelli of 2-day-old pupae, when a retinogenous and a lentinogenous cell layer can be clearly distinguished, cell membranes of the distal part of two photoreceptor cells begin to interdigitate with each other and so start to form the definitive microvilli. At the beginning the microvilli often occupy the whole width of the developing rhabdom (Fig. 1).

Actin and α-tubulin immuno-EM labelings reveal differences in intra versus interphotoreceptor matrix

1990 ◽  
Vol 48 (3) ◽  
pp. 466-467
Author(s):  
Matti Järvilehto ◽  
Riitta Harjula
Keyword(s):  
Compound Eye ◽  
Frozen Section ◽  
Smooth Muscle Actin ◽  
Photoreceptor Cells ◽  
Immune Serum ◽  
Cell Organelles ◽  
Calliphora Erythrocephala ◽  
Optical Axes ◽  
Interphotoreceptor Matrix ◽  
Similar Kind

The photoreceptor cells in the compound eyes of higher diptera are clustered in groups (ommatidia) of eight receptor cells. The cells from six adjacent ommatidia are organized into optical units, neuro-ommatia sharing the same visual field. In those ommatidia the optical axes of the photopigment containing structures (rhabdomeres) are parallel. The rhabdomeres of the photoreceptor cells are separated from each other by an interstitial i.e innerommatidial space (IOS). In the photoreceptor cell body, besides of the normal cell organelles, a cellular matrix is a structurally apparent component. Similar kind of reticular formation is also found in the IOS containing some unidentified filamentary substance, of which composition and functional significance for optical properties of vision is the aim of this report.The prefixed (2% PA + 0.2% GA in 0.1-n phosphate buffer, pH 7.4, for 1h), frozen section blocks of the compound eye of the blowfly (Calliphora erythrocephala) were prepared by immuno-cryo-techniques. The ultrathin cryosections were incubated with antibodies of monoclonal α-tubulin and polyclonal smooth muscle actin. Control labelings of excess of antigen, non-immune serum and non-present antibody were perforated.

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