Kinase activity profiling identifies putative downstream targets of cGMP/PKG signaling in inherited retinal neurodegeneration

AbstractInherited retinal diseases (IRDs) are a group of neurodegenerative disorders that lead to photoreceptor cell death and eventually blindness. IRDs are characterised by a high genetic heterogeneity, making it imperative to design mutation-independent therapies. Mutations in a number of IRD disease genes have been associated with a rise of cyclic 3’,5’-guanosine monophosphate (cGMP) levels in photoreceptors. Accordingly, the cGMP-dependent protein kinase (PKG) has emerged as a new potential target for the mutation-independent treatment of IRDs. However, the substrates of PKG and the downstream degenerative pathways triggered by its activity have yet to be determined. Here, we performed kinome activity profiling of different murine organotypic retinal explant cultures (diseased rd1 and wild-type controls) using multiplex peptide microarrays to identify proteins whose phosphorylation was significantly altered by PKG activity. In addition, we tested the downstream effect of a known PKG inhibitor CN03 in these organotypic retina cultures. Among the PKG substrates were potassium channels belonging to the Kv1 family (KCNA3, KCNA6), Cyclic AMP-responsive element-binding protein 1 (CREB1), DNA topoisomerase 2-α (TOP2A), 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (F263), and the glutamate ionotropic receptor kainate 2 (GRIK2). The retinal expression of these PKG targets was further confirmed by immunofluorescence and could be assigned to various neuronal cell types, including photoreceptors, horizontal cells, and ganglion cells. Taken together, this study confirmed the key role of PKG in photoreceptor cell death and identified new downstream targets of cGMP/PKG signalling that will improve the understanding of the degenerative mechanisms underlying IRDs.

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Distinct and Atypical Intrinsic and Extrinsic Cell Death Pathways between Photoreceptor Cell Types upon Specific Ablation of Ranbp2 in Cone Photoreceptors

PLoS Genetics ◽

10.1371/journal.pgen.1003555 ◽

2013 ◽

Vol 9 (6) ◽

pp. e1003555 ◽

Cited By ~ 21

Author(s):

Kyoung-in Cho ◽

MdEmdadul Haque ◽

Jessica Wang ◽

Minzhong Yu ◽

Ying Hao ◽

...

Keyword(s):

Cell Death ◽

Photoreceptor Cell ◽

Cell Types ◽

Cone Photoreceptors ◽

Cell Death Pathways

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Retinal input influences pace of neurogenesis but not cell-type configuration of the visual forebrain

10.1101/2021.11.15.468630 ◽

2021 ◽

Author(s):

Shachar Sherman ◽

Koichi Kawakami ◽

Herwig Baier

Keyword(s):

Visual Information ◽

Visual Stimulation ◽

Ganglion Cells ◽

Neuronal Cell ◽

Cell Types ◽

Vertebrate Brain ◽

Relative Contribution ◽

Retinal Input ◽

And Migration ◽

The Brain

The brain is assembled during development by both innate and experience-dependent mechanisms1-7, but the relative contribution of these factors is poorly understood. Axons of retinal ganglion cells (RGCs) connect the eye to the brain, forming a bottleneck for the transmission of visual information to central visual areas. RGCs secrete molecules from their axons that control proliferation, differentiation and migration of downstream components7-9. Spontaneously generated waves of retinal activity, but also intense visual stimulation, can entrain responses of RGCs10 and central neurons11-16. Here we asked how the cellular composition of central targets is altered in a vertebrate brain that is depleted of retinal input throughout development. For this, we first established a molecular catalog17 and gene expression atlas18 of neuronal subpopulations in the retinorecipient areas of larval zebrafish. We then searched for changes in lakritz (atoh7-) mutants, in which RGCs do not form19. Although individual forebrain-expressed genes are dysregulated in lakritz mutants, the complete set of 77 putative neuronal cell types in thalamus, pretectum and tectum are present. While neurogenesis and differentiation trajectories are overall unaltered, a greater proportion of cells remain in an uncommitted progenitor stage in the mutant. Optogenetic stimulation of a pretectal area20,21 evokes a visual behavior in blind mutants indistinguishable from wildtype. Our analysis shows that, in this vertebrate visual system, neurons are produced more slowly, but specified and wired up in a proper configuration in the absence of any retinal signals.

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TNFα-induced AMPA-receptor trafficking in CNS neurons; relevance to excitotoxicity?

Neuron Glia Biology ◽

10.1017/s1740925x05000608 ◽

2004 ◽

Vol 1 (3) ◽

pp. 263-273 ◽

Cited By ~ 41

Author(s):

DMITRI LEONOUDAKIS ◽

STEVEN P. BRAITHWAITE ◽

MICHAEL S. BEATTIE ◽

ERIC C. BEATTIE

Keyword(s):

Cell Death ◽

Inflammatory Response ◽

Hippocampal Neurons ◽

Neuronal Damage ◽

Neuronal Cell Death ◽

Neuronal Cell ◽

Cell Types ◽

Synaptic Function ◽

Ampar Trafficking ◽

Novel Target

Injury and disease in the CNS increases the amount of tumor necrosis factor α (TNFα) that neurons are exposed to. This cytokine is central to the inflammatory response that occurs after injury and during prolonged CNS disease, and contributes to the process of neuronal cell death. Previous studies have addressed how long-term apoptotic-signaling pathways that are initiated by TNFα might influence these processes, but the effects of inflammation on neurons and synaptic function in the timescale of minutes after exposure are largely unexplored. Our published studies examining the effect of TNFα on trafficking of AMPA-type glutamate receptors (AMPARs) in hippocampal neurons demonstrate that glial-derived TNFα causes a rapid (<15 minute) increase in the number of neuronal, surface-localized, synaptic AMPARs leading to an increase in synaptic strength. This indicates that TNFα-signal transduction acts to facilitate increased surface localization of AMPARs from internal postsynaptic stores. Importantly, an excess of surface localized AMPARs might predispose the neuron to glutamate-mediated excitotoxicity and excessive intracellular calcium concentrations, leading to cell death. This suggests a new mechanism for excitotoxic TNFα-induced neuronal death that is initiated minutes after neurons are exposed to the products of the inflammatory response.Here we review the importance of AMPAR trafficking in normal neuronal function and how abnormalities that are mediated by glial-derived cytokines such as TNFα can be central in causing neuronal disorders. We have further investigated the effects of TNFα on different neuronal cell types and present new data from cortical and hippocampal neurons in culture. Finally, we have expanded our investigation of the temporal profile of the action of this cytokine relevant to neuronal damage. We conclude that TNFα-mediated effects on AMPAR trafficking are common in diverse neuronal cell types and very rapid in their onset. The abnormal AMPAR trafficking elicited by TNFα might present a novel target to aid the development of new neuroprotective drugs.

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Insertion of the βGeo Promoter Trap into the Fem1c Gene of ROSA3 Mice

Molecular and Cellular Biology ◽

10.1128/mcb.24.9.3794-3803.2004 ◽

2004 ◽

Vol 24 (9) ◽

pp. 3794-3803 ◽

Cited By ~ 6

Author(s):

Cassandra L. Schlamp ◽

Andrew T. Thliveris ◽

Yan Li ◽

Louis P. Kohl ◽

Claudia Knop ◽

...

Keyword(s):

Cell Death ◽

Ganglion Cells ◽

Neuronal Cell Death ◽

Insertion Site ◽

Neuronal Cell ◽

Pyramidal Cells ◽

Coding Region ◽

Protein Levels ◽

Molecular Events ◽

Promoter Trap

ABSTRACT ROSA3 mice were developed by retroviral insertion of the βGeo gene trap vector. Adult ROSA3 mice exhibit widespread expression of the trap gene in epithelial cells found in most organs. In the central nervous system the highest expression of βGeo is found in CA1 pyramidal cells of the hippocampus, Purkinje cells of the cerebellum, and ganglion cells of the retina. Characterization of the genomic insertion site for βGeo in ROSA3 mice shows that the trap vector is located in the first intron of Fem1c, a gene homologous to the sex-determining gene fem-1 of Caenorhabditis elegans. Transcription of the Rosa3 allele (R3) yields a spliced message that includes the first exon of Fem1c and the βGeo coding region. Although normal processing of the Fem1c transcript is disrupted in homozygous Rosa3 (Fem1cR3/R3 ) mice, some tissues show low levels of a partially processed transcript containing exons 2 and 3. Since the entire coding region of Fem1c is located in these two exons, Fem1cR3/R3 mice may still be able to express a putative FEM1C protein. To this extent, Fem1cR3/R3 mice show no adverse effects in their sexual development or fertility or in the attenuation of neuronal cell death, another function that has been attributed to both fem-1 and a second mouse homolog, Fem1b. Examination of βGeo expression in ganglion cells after exposure to damaging stimuli indicates that protein levels are rapidly depleted prior to cell death, making the βGeo reporter gene a potentially useful marker to study early molecular events in damaged neurons.

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Neuronal apoptosis: signal and cell diversity

Colombia Medica ◽

10.25100/cm.v40i1.634 ◽

1969 ◽

Vol 40 (1) ◽

pp. 124-133

Author(s):

Lina Vanessa Becerra ◽

Hernán José Pimienta

Keyword(s):

Cell Death ◽

Programmed Cell Death ◽

Neuronal Response ◽

Neuronal Cell ◽

Cell Types ◽

Point Of View ◽

Trophic Factors ◽

Cell Diversity ◽

Apoptotic Pathways ◽

The Brain

Programmed cell death occurs as a physiological process during development. In the brain and spinal cord this event determines the number and location of the different cell types. In adulthood, programmed cell death or apoptosis is more restricted but it may play a major role in different acute and chronic pathological entities. However, in contrast to other tissues where apoptosis has been widely documented from a morphological point of view, in the central nervous system complete anatomical evidence of apoptosis is scanty. In spite of this there is consensus about the activation of different signal systems associated to programmed cell death. In the present article we attempt to summarize the main apoptotic pathways so far identified in nervous tissue. Considering that apoptotic pathways are multiple, the neuronal cell types are highly diverse and specialized and that neuronal response to injury and survival depends upon tissue context, (i.e., preservation of connectivity, glial integrity and cell matrix, blood supply and trophic factors availability) what is relevant for the apoptotic process in a sector of the brain may not be important in another.

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The Uptake and Localization of Catecholamines in Chick Embryo Sympathetic Neurons in Tissue Culture

Journal of Cell Science ◽

10.1242/jcs.4.3.677 ◽

1969 ◽

Vol 4 (3) ◽

pp. 677-691

Author(s):

J. M. ENGLAND ◽

M. N. GOLDSTEIN

Keyword(s):

Tissue Culture ◽

Chick Embryo ◽

Ganglion Cells ◽

Sympathetic Neurons ◽

Neuronal Cell ◽

Cell Types ◽

Axon Terminals ◽

Dense Core Granules ◽

Insoluble Compounds ◽

Dorsal Root Ganglion Cells

The uptake of exogenous [3H]dopamine, [3H]norepinephrine,[3H]epinephrine by dissociated chick embryo sympathetic neurons growing in tissue culture was studied by autoradiography. The neurons, growing in a medium containing nerve growth factor, rapidly and specifically took up all three catecholamines for at least 60 days, while no uptake was observed in several other cell types, including satellite cells and chick dorsal-root ganglion cells. The uptake was dependent on the concentration of the catecholamine and the duration of the pulse and was inhibited by cocaine and several sympathomimetic amines. Labelling was visualized only with fixatives which react with catecholamines to form water-insoluble compounds. Autoradiographs showed that the label was much denser over the axons than the cell bodies. The label was distributed uniformly along the axons and did not seem to be preferentially localized at the axon terminals or varicosities which contain aggregates of dense core granules. These observations indicate that a large portion of the exogenous 3[H]catecholamine is localized in an extragranular compartment and suggest that the differentiated function of the sympathetic neuronal cell membrane, which plays an important role in uptake, is retained after prolonged tissue culture.

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Effect of nerve growth factor on the release of inflammatory mediators by mature human basophils

Blood ◽

10.1182/blood.v79.10.2662.2662 ◽

1992 ◽

Vol 79 (10) ◽

pp. 2662-2669 ◽

Cited By ~ 4

Author(s):

SC Bischoff ◽

CA Dahinden

Keyword(s):

Nerve Growth Factor ◽

Growth Factor ◽

Inflammatory Mediators ◽

Ganglion Cells ◽

Neuronal Cell ◽

Cell Types ◽

Cell Fractionation ◽

Hematopoietic Growth Factors ◽

Nerve Growth ◽

Human Basophils

Abstract Nerve growth factor (NGF) is a neurotrophic cytokine known to regulate the survival and function of peripheral and central neuronal cells. Recently, the spectrum of action could be extended to non-neuronal cell types such as rat mast cells and human B lymphocytes. The present study shows that NGF affects the function of mature human basophils isolated from the peripheral blood of healthy donors. Both murine NGF 7S and recombinant human NGF beta enhance histamine release and strongly modulate the formation of lipid mediators by basophils in response to various stimuli. This priming effect of NGF on basophils occurs rapidly within 10 to 15 minutes of preincubation, is dose-dependent, and requires similarly low concentrations (1 to 40 pmol/L) of human NGF beta as the induction of neurite outgrowth in ganglion cells. Cell fractionation studies indicate that NGF acts directly on human basophils without an involvement of other cell types, suggesting the presence of high-affinity NGF receptors on basophils. NGF by itself (up to 4 nmol/L of human NGF beta) does not induce the release of inflammatory mediators directly. The effect of human NGF on basophil mediator release is similar to that of the hematopoietic growth factors interleukin-3, interleukin-5, and granulocyte-macrophage colony- stimulating factor. The present study further demonstrates that NGF acts as a pleiotropic cytokine at the interface between the nervous and the immune system, and that NGF may be involved in inflammatory processes and hypersensitivity reactions.

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