Journal: Frontiers in Cellular Neuroscience

Article Title: Morphology and connectivity of retinal horizontal cells in two avian species

doi: 10.3389/fncel.2025.1558605

Figure Lengend Snippet: Primary and secondary antibodies used in this study.

Article Snippet: PSD95 , Recombinant protein corresponding to human PSD95 , Mouse , 1:500 (s) , Millipore, MABN68, RRID:AB_10807979.

Techniques: Recombinant, Derivative Assay

Journal: Frontiers in Cellular Neuroscience

Article Title: Morphology and connectivity of retinal horizontal cells in two avian species

doi: 10.3389/fncel.2025.1558605

Figure Lengend Snippet: The axon-bearing H1 horizontal cell in the peripheral chicken retina contacts all cones. (A) Maximum projection of a dye-injected H1 horizontal cell, revealing a dense and narrow dendritic field and an axon (arrows). Double labeling with PSD95 reveals the stratification of photoreceptor terminals in three layers (labeled 1–3) of the outer plexiform layer (OPL). Please note that for PSD95, the maximum projection of a substack is shown to better illustrate the three layers. (B) Single optical sections at different positions of the confocal stack. H1 cell dendrites contact cones in all three layers of the OPL (arrowheads). Whether or not rods are also contacted by the dendritic field could not be resolved. Please note that the H1 soma was saturated on purpose to better reveal the thin dendrites. Scale: 10 μm (A) , 2 μm (B) .

Article Snippet: PSD95 , Recombinant protein corresponding to human PSD95 , Mouse , 1:500 (s) , Millipore, MABN68, RRID:AB_10807979.

Techniques: Injection, Labeling

Journal: Frontiers in Cellular Neuroscience

Article Title: Morphology and connectivity of retinal horizontal cells in two avian species

doi: 10.3389/fncel.2025.1558605

Figure Lengend Snippet: H2 horizontal cells in the peripheral chicken retina make selective contacts to the accessory member of the double cone photoreceptors. (A) Dye-injected H2 horizontal cell, revealing a large dendritic tree which is only branching in the terminal endings. A maximum projection is shown. Double labeling with PSD95 reveals the stratification of photoreceptor terminals in three layers (labeled 1–3) of the outer plexiform layer (OPL). Please note that for PSD95, the maximum projection of a substack is shown to better illustrate the three layers. (B) Maximum projections of substacks (12–18 optical sections). Please note that the H2 soma was saturated on purpose to better reveal the thin dendrites. The vast majority of H2 cell dendrites contact the accessory members of the double cones in the most distal OPL layer (1, asterisks), while avoiding photoreceptor terminals in layer 3 which belong to violet and blue cones ( ; ), marked by a circle. However, one dendrite seems to contact a green or red cone in layer 2 of the OPL (arrowhead). Scale: 10 μm (A) , 2 μm (B) .

Article Snippet: PSD95 , Recombinant protein corresponding to human PSD95 , Mouse , 1:500 (s) , Millipore, MABN68, RRID:AB_10807979.

Techniques: Injection, Labeling

Journal: Frontiers in Cellular Neuroscience

Article Title: Morphology and connectivity of retinal horizontal cells in two avian species

doi: 10.3389/fncel.2025.1558605

Figure Lengend Snippet: Wide-field horizontal cell (H3 or H4) in the peripheral chicken retina avoiding the outermost layer of the outer plexiform layer. (A) Maximum projection of a dye-injected wide-field horizontal cell, revealing a flat dendritic field with processes mostly confined to layer 2 of the outer plexiform layer. Whether this cell represents an H3 or H4 cell is not possible to discern. Double labeling with PSD95 reveals the stratification of photoreceptor terminals in three layers (labeled 1–3) of the outer plexiform layer (OPL). Please note that for PSD95, the maximum projection of a substack is shown to better illustrate the three layers. (B) Maximum projections of substacks (30–35 optical sections) of the confocal stack. H3/4 cell dendrites contact mostly red and/or green cones in layer 2 of the OPL (arrowheads), while avoiding rods and double cones in the most distal layer (1) of the OPL. Rarely, H3/4 cell dendrites reach out to violet/blue cones (circle) in the most proximal layer (3) of the OPL ( ; ). However, whether these dendrites which do not invaginate the cone pedicle represent true contacts is unclear. Please note that the H3/4 soma was saturated on purpose to better reveal the thin dendrites. Scale: 10 μm (A) , 2 μm (B) .

Article Snippet: PSD95 , Recombinant protein corresponding to human PSD95 , Mouse , 1:500 (s) , Millipore, MABN68, RRID:AB_10807979.

Techniques: Injection, Labeling

Journal: Frontiers in Cellular Neuroscience

Article Title: Synaptic Scaffolds, Ion Channels and Polyamines in Mouse Photoreceptor Synapses: Anatomy of a Signaling Complex

doi: 10.3389/fncel.2021.667046

Figure Lengend Snippet: Antibodies used in this study.

Article Snippet: PSD95 , Ms , Fusion protein of human PSD95 (aa77–299) , UC Davis/NIH Neuromab, Davis, CA, United States , 75-028 AB_2292909 , 1:500.

Techniques: Recombinant, Derivative Assay, Purification

Journal: Frontiers in Cellular Neuroscience

Article Title: Synaptic Scaffolds, Ion Channels and Polyamines in Mouse Photoreceptor Synapses: Anatomy of a Signaling Complex

doi: 10.3389/fncel.2021.667046

Figure Lengend Snippet: Localization of synaptic scaffolds PSD95, SAP97, and CASK in the mouse retina. (A) Immunostaining for PSD95 (green) with DAPI counterstaining (blue). Labels for retinal nuclear layers are: ONL, outer nuclear layer; INL, inner nuclear layer; GCL, ganglion cell layer. PSD95 labeling was prominent in the outer plexiform layer (OPL—between ONL and INL) and very weak in the inner plexiform layer (IPL—between INL and GCL). Two examples of non-specific labeling of blood vessels by the secondary antibody are indicated by asterisks. Two μm confocal stack. (B) Higher magnification view of the OPL showing PSD95 labeling of rod and cone terminals. Single confocal section. (C) SAP97 immunostaining revealed punctate and diffuse labeling in both OPL and IPL. Retinal layers are aligned as in (A) . One μm confocal stack. (D) Higher magnification view of the OPL shows SAP97 labeling to be diffusely distributed throughout the layer. One μm confocal stack. (E) CASK immunostaining revealed moderately strong labeling in the OPL and very strong labeling throughout the IPL. Retinal layers are aligned as in (A) . Two examples of non-specific labeling of blood vessels by the secondary antibody are indicated by asterisks. Two μm confocal stack. (F) Higher magnification view of the OPL shows CASK labeling to be diffusely distributed throughout the layer. Two μm confocal stack. (G) Average mRNA expression levels of PSD95 (Dlg4), SAP97 (Dlg1) and CASK (Cask) in mouse retina by single-cell RNA Sequencing. Of note in the OPL is some expression of PSD95 in horizontal cells, broad, low-level expression of SAP97, and expression of CASK most prominently in bipolar cells. Data adapted from . See section “Materials and Methods” for caveats about data interpretation. Abbreviations used: RPE, retinal pigmented epithelium; V/E cells, vascular endothelial cells; RGC, retinal ganglion cells; AC, amacrine cell; BC, bipolar cell; MG, Müller glia.

Article Snippet: PSD95 , Ms , Fusion protein of human PSD95 (aa77–299) , UC Davis/NIH Neuromab, Davis, CA, United States , 75-028 AB_2292909 , 1:500.

Techniques: Immunostaining, Labeling, Expressing, RNA Sequencing

Journal: Frontiers in Cellular Neuroscience

Article Title: Synaptic Scaffolds, Ion Channels and Polyamines in Mouse Photoreceptor Synapses: Anatomy of a Signaling Complex

doi: 10.3389/fncel.2021.667046

Figure Lengend Snippet: Localization of synaptic scaffolds SAP102 and Chapsyn110 in the mouse retina. (A) Immunostaining for SAP102 (green) with DAPI counterstaining (blue). Labels for retinal nuclear layers are as in . SAP102 displayed partially punctate and partially diffuse labeling throughout both inner and outer plexiform layers. Five μm confocal stack. (B) Higher magnification view of the OPL labeled for SAP102 (green) and PSD95 (red). Two μm confocal stack. (C) Average mRNA expression levels of SAP102 (Dlg3) and Chapsyn110 (Dlg2) in mouse retina from single-cell transcriptome data. SAP102 displayed low levels of expression in horizontal cells and Müller glia, and lower levels in rods and cones. Chapsyn110 displayed prominent expression in horizontal cells and some expression in bipolar cells, particularly ON types. Data adapted from . (D) Immunostaining for Chapsyn110 revealed a sharply punctate distribution in both the outer and inner plexiform layers. Retinal layers are aligned as in (A) . Several prominent blood vessels non-specifically labeled by the secondary antibody are present, with two denoted by asterisks. Five μm confocal stack. (E) Higher magnification view of the OPL labeled for Chapsyn110 (green) and mGluR6 (red), labeling the tips of On bipolar cell dendrites. Chapsyn110 aligned closely with mGluR6, but did not co-localize with it. Arrowheads point to clusters of labeling for both markers at a cone pedicle. Three μm confocal stack.

Article Snippet: PSD95 , Ms , Fusion protein of human PSD95 (aa77–299) , UC Davis/NIH Neuromab, Davis, CA, United States , 75-028 AB_2292909 , 1:500.

Techniques: Immunostaining, Labeling, Expressing

Journal: Frontiers in Cellular Neuroscience

Article Title: Synaptic Scaffolds, Ion Channels and Polyamines in Mouse Photoreceptor Synapses: Anatomy of a Signaling Complex

doi: 10.3389/fncel.2021.667046

Figure Lengend Snippet: Localization of inward rectifier potassium channel Kir2.1 in mouse retina. (A) Immunostaining for Kir2.1 (rabbit antibody; red) with DAPI counterstaining (blue) and PSD95 (green) to label photoreceptor terminals. Labels for retinal nuclear layers are as in . Kir2.1 is diffusely present in the IPL, but strongly labeled at the inner limiting membrane (arrowheads) and in the OPL. Five μm confocal stack. (B) Higher magnification view of the OPL reveals Kir2.1 (red) labeling largely below the photoreceptor terminals (green; PSD95 labeling), but with some diffuse and punctate labeling among the terminals. Two μm confocal stack. (Ci) Kir2.1 labeling (guinea pig antibody; red) colocalizes with Calbindin labeled horizontal cells (green) in the OPL. (Cii) Kir2.1 labeling in isolation. (Di) Another view of horizontal cells in the OPL (Calbindin labeling; green) along with mGluR6 labeling (magenta) to show locations of On bipolar cell dendritic tips. Clusters of mGluR6 label indicate cone terminals; three examples are indicated with paired arrowheads. Six μm confocal stack. (Dii) Kir2.1 labeling (rabbit antibody; red) in the same section. (Diii) Merged view of all three labels. Kir2.1 shows both diffuse and punctate labeling in the vicinity of horizontal cell axon terminal projections contacting rods, but little labeling near clusters of dendritic processes contacting cones. (Ei) Higher magnification view of a horizontal cell labeled with Calbindin antibody (green). Several representative axon terminal tips are highlighted with arrowheads. One μm confocal stack. (Eii) Kir2.1 labeling in the same section. (Eiii) Merged view of the two labels shows that tips of horizontal cell axon terminal processes contain punctate clusters of Kir2.1 labeling (arrowheads). (F) Average mRNA expression levels of Kir2.1 (Kcnj2) and kainate receptor subunits GluR6 (Grik2) and GluR7 (Grik3) in mouse retina from single-cell transcriptome data. Kir2.1 is most prominently expressed in horizontal cells and essentially absent from Müller glia. The kainate receptor subunit GluR6 is also found in horizontal cells and Off bipolar cells, but GluR7 is absent from these cell types. Data adapted from .

Article Snippet: PSD95 , Ms , Fusion protein of human PSD95 (aa77–299) , UC Davis/NIH Neuromab, Davis, CA, United States , 75-028 AB_2292909 , 1:500.

Techniques: Immunostaining, Labeling, Membrane, Isolation, Expressing

Journal: Frontiers in Cellular Neuroscience

Article Title: Synaptic Scaffolds, Ion Channels and Polyamines in Mouse Photoreceptor Synapses: Anatomy of a Signaling Complex

doi: 10.3389/fncel.2021.667046

Figure Lengend Snippet: Differences in polyamine distribution between daytime and nighttime mouse retina. (A) Double labeling for polyamines (red) and Calbindin to label horizontal cells (green) in a retina sampled in photopic light 5 h after light onset (Day). Polyamine labeling is particularly prominent in the OPL. Five μm confocal stack. (B) Higher magnification view of the OPL in daytime retina. Prominent polyamine labeling is just above the horizontal cells (green; Calbindin label). Five μm confocal stack. (C) Double labeling for polyamines (red) and PSD95 (green) reveals that polyamines are located within photoreceptor terminals. Single confocal section. (D) Double labeling for polyamines (red) and Calbindin to label horizontal cells (green) in a retina sampled in darkness 5 h after light offset (Night). Polyamine labeling is overall less intense with distinctly less labeling in the OPL. Seven μm confocal stack. (E) Higher magnification view of the OPL in nighttime retina. Polyamine labeling (red) above horizontal cells (green) is far less prominent than in the daytime. Five μm confocal stack. (F) Double labeling for polyamines (red) and PSD95 (green) reveals that the reduced polyamine labeling in the nighttime OPL is still contained within photoreceptor terminals. Single confocal section. (G) Quantitative assessment of average polyamine labeling intensity in rod and cone terminals in day and night conditions. Points represent mean labeling intensity for all terminals measured for an individual animal (see section “Materials and Methods”). * p < 0.05, ** p < 0.01, 2-way ANOVA with Tukey’s multiple comparisons.

Article Snippet: PSD95 , Ms , Fusion protein of human PSD95 (aa77–299) , UC Davis/NIH Neuromab, Davis, CA, United States , 75-028 AB_2292909 , 1:500.

Techniques: Labeling

Journal: Frontiers in Cellular Neuroscience

Article Title: Synaptic Scaffolds, Ion Channels and Polyamines in Mouse Photoreceptor Synapses: Anatomy of a Signaling Complex

doi: 10.3389/fncel.2021.667046

Figure Lengend Snippet: Localization of vesicular polyamine transporter SLC18B1 in mouse retina. (A) SLC18B1 immunostaining (red) with DAPI counterstain (blue). Labels for retinal nuclear layers are as in . SLC18B1 was present diffusely through most of the retina, with more prominent labeling in the OPL and at the inner limiting membrane (arrowheads). Four μm confocal stack. (Bi) Higher magnification view of the OPL double labeled for Slc18B1 (red) and PSD95 (green) to label photoreceptor terminals. Eight μm confocal stack. (Bii) SLC18B1 labeling in isolation. Labeling is diffuse throughout the area of photoreceptor terminals and below them. Some areas of dense labeling (arrowhead) resemble Müller glial cell processes ascending through the ONL. (C) Average mRNA expression level of SLC18B1 in mouse retina from single-cell transcriptome data. SLC18B1 is present at very low levels in most retinal cell types, with horizontal cells and Müller glia showing somewhat higher levels. Rods also contained SLC18B1 transcripts. Data adapted from .

Article Snippet: PSD95 , Ms , Fusion protein of human PSD95 (aa77–299) , UC Davis/NIH Neuromab, Davis, CA, United States , 75-028 AB_2292909 , 1:500.

Techniques: Immunostaining, Labeling, Membrane, Isolation, Expressing

Journal: The Journal of comparative neurology

Article Title: Cone synapses in mammalian retinal rod bipolar cells

doi: 10.1002/cne.24456

Figure Lengend Snippet: Antibody characterization

Article Snippet: 270–427 Recombinant Protein BD transduction, 610107, Clone 3/PKCα (RUO), 1: 200, Mouse, Monoclonal RRID: AB_397513 ( Elshatory et al., 2007 ; Pang et al., 2013 ) Calbindin D-28k Recombinant rat calbindin D-28k (CB) protein Swant, CB38, 1: 1000, Rabbit, Polyclonal RRID: AB_10000340 ( Fischer et al., 2008 ; Zhang et al., 2003 ) Calbindin D-28k Bovine kidney calbindin-D Sigma, C9848, clone CB955, 1: 200, Mouse, Monoclonal RRID: AB_476894 ( Fischer et al., 2008 ; Zhang et al., 2003 ) PSD-95 Recombinant protein corresponding to human PSD95 Millipore, MABN68, clone K28/43, 1: 100, Mouse, Monoclonal RRID: AB_10807979 ( Ivanova et al., 2013 ; Fischer et al., 2008 ) GNB5 GNB5 ( {"type":"entrez-protein","attrs":{"text":"NP_057278","term_id":"20336270","term_text":"NP_057278"}} NP_057278 , aa.

Techniques: Recombinant, Transduction, Purification

Journal: The Journal of comparative neurology

Article Title: Cone synapses in mammalian retinal rod bipolar cells

doi: 10.1002/cne.24456

Figure Lengend Snippet: Baboon cone-RBC synapses. Retina preparations are triple- (a to d) or double-labeled. Cone somas and pedicles are brightly labeled for calbindin D-28k (Calb) (c, d). PNA intensively labels cone inner segments (a, c, e) and reveals clusters of puncta in the basal membrane of cone pedicles (d). Each cluster of PNA-positive puncta belongs to a cone pedicle (d). Consecutive confocal optical sections of a rectangular region in b show that some PKCα-labeled RBC dendrites colocalize with PNA (e). Some RBC dendrites coincide with PNA in cone pedicles (see arrows) in retinal slices (f, upper-peripheral retina, lower-para-central retina) and cone telodendrites in the flat-mount retina (h). h displays overexposed images of consecutive horizontal confocal optical sections of a cone pedicle and its telodendrites (in the circle). In retinal slices (g) large triangular cone pedicles are positively labeled for PSD95 (triangle) and distinguishable from small oval-shaped rod spherules (asterisks). RBC dendrites contact rod spherules and one cone pedicle (closed triangle) but do not contact the other cone pedicle (open triangle). Scale bars are 20 µm in a, c and f and 5 µm in the rest images.

Article Snippet: 270–427 Recombinant Protein BD transduction, 610107, Clone 3/PKCα (RUO), 1: 200, Mouse, Monoclonal RRID: AB_397513 ( Elshatory et al., 2007 ; Pang et al., 2013 ) Calbindin D-28k Recombinant rat calbindin D-28k (CB) protein Swant, CB38, 1: 1000, Rabbit, Polyclonal RRID: AB_10000340 ( Fischer et al., 2008 ; Zhang et al., 2003 ) Calbindin D-28k Bovine kidney calbindin-D Sigma, C9848, clone CB955, 1: 200, Mouse, Monoclonal RRID: AB_476894 ( Fischer et al., 2008 ; Zhang et al., 2003 ) PSD-95 Recombinant protein corresponding to human PSD95 Millipore, MABN68, clone K28/43, 1: 100, Mouse, Monoclonal RRID: AB_10807979 ( Ivanova et al., 2013 ; Fischer et al., 2008 ) GNB5 GNB5 ( {"type":"entrez-protein","attrs":{"text":"NP_057278","term_id":"20336270","term_text":"NP_057278"}} NP_057278 , aa.

Techniques: Labeling

Journal: The Journal of comparative neurology

Article Title: Membrane-Associated Guanylate Kinase scaffolds organize a horizontal cell synaptic complex restricted to invaginating contacts with photoreceptors

doi: 10.1002/cne.24101

Figure Lengend Snippet: Antibodies used in this study

Article Snippet: PSD95 , Ms , Fusion protein of human PSD95 (aa77-299) , UC Davis/NIH Neuromab, Davis, CA , 75-028 RRID: AB_2292909 , 1:500 , Puthussery et al., 2014.

Techniques: Derivative Assay

Journal: The Journal of comparative neurology

Article Title: Membrane-Associated Guanylate Kinase scaffolds organize a horizontal cell synaptic complex restricted to invaginating contacts with photoreceptors

doi: 10.1002/cne.24101

Figure Lengend Snippet: A, Vertical section of rabbit retina labeled for PSD95. Prominent immunoreactivity in the OPL encircled photoreceptor terminals. In the IPL immunofluorescence was found in the form of sparse, very small puncta. B, SAP97-IR was found in the OPL, where rod and cone photoreceptor terminals were labeled intensively. Strong labeling was concentrated in the cytoplasm of rod spherules and cone pedicles. In the IPL immunofluorescence was found in the form of sparse puncta. C, SAP102-IR appeared as clusters of puncta in the OPL surrounded by sparser puncta. Immunolabeling in the IPL was weak and punctate. D, Chapsyn-110 IR had a similar labeling pattern as observed with SAP102 in the OPL. Chapsyn-110 immunolabeling was punctate and much stronger than the other MAGUKs in the IPL. Scale bars: 10 µm.

Article Snippet: PSD95 , Ms , Fusion protein of human PSD95 (aa77-299) , UC Davis/NIH Neuromab, Davis, CA , 75-028 RRID: AB_2292909 , 1:500 , Puthussery et al., 2014.

Techniques: Labeling, Immunofluorescence, Immunolabeling