Submit to IJMS Review for IJMS Propose a Special Issue

Journal Menu

Journal Browser

cGMP-Signalling in Cells: Molecular and Functional Features

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Keywords
Published Papers

A special issue of International Journal of Molecular Sciences (ISSN 1422-0067). This special issue belongs to the section "Biochemistry".

Deadline for manuscript submissions: closed (31 January 2018) | Viewed by 72663

Share This Special Issue

Special Issue Editor

Prof. Dr. Jens Schlossmann

E-Mail Website
Guest Editor

Pharmakologie und Toxikologie, Institut für Pharmazie, Universitätsstr. 31, 93040 Regensburg, Germany
Interests: cGMP; signaling proteins; signal transduction pathways; kinases
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Cellular signalling by cGMP is an expanding field which comprises molecular function and (patho)physiology in various organ systems. cGMP synthesis, degradation and function are modulated by a variety of signalling proteins and signal transduction pathways. Stuctural, biochemical and (patho)physiological aspects have been strongly developed in the last decade, e.g., regarding cardiovascular, renal, pulmonary and neuronal function. Dysregulation of cGMP generators (guanylyl cyclases), modulators (phosphodiesterases) and signalling molecules (e.g., kinases/substrates, channels) have been elucidated as cause of pathophysiological processes and diseases. Pharmacological approaches have been propagated into pharmacological treatments including hypertension and cardiovascular diseases. Therefore, the molecular and functional understanding of the diverse cGMP generators, signalling proteins and signal transduction pathways is fundamental for the insight into their (patho)physiological processes. The scope of the special issue is to summarize and enlarge the knowledge of these signalling processes and networks in diverse cells/tissues and to link it to (patho)physiological and pharmacological functions.

Therefore, authors are invited to submit original research and review articles which address the progress and current standing of cGMP signalling.

Topics include, but are not limited to:

Identification of and new molecular and functional aspects in cGMP-signalling molecules and pathways
Analysis of cGMP-signal generation, modulation, recognition and/or its transduction into physiological/pathophysiological responses
Techniques for the analysis and identification of cGMP signalling molecules, complexes, pathways and networks

Prof. Dr. Jens Schlossmann
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. International Journal of Molecular Sciences is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. There is an Article Processing Charge (APC) for publication in this open access journal. For details about the APC please see here. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

cGMP
Signalling molecules
Signalling complexes
Signal transduction
Guanylyl cyclases
Kinases
Phosphodiesterases
Channels
Substrate Proteins
Pharmacology

Published Papers (12 papers)

Download All Papers

Research

Jump to: Review

20 pages, 5344 KiB

Open AccessArticle

cGMP Imaging in Brain Slices Reveals Brain Region-Specific Activity of NO-Sensitive Guanylyl Cyclases (NO-GCs) and NO-GC Stimulators

by Stefanie Peters, Michael Paolillo, Evanthia Mergia, Doris Koesling, Lea Kennel, Achim Schmidtko, Michael Russwurm and Robert Feil

Int. J. Mol. Sci. 2018, 19(8), 2313; https://doi.org/10.3390/ijms19082313 - 07 Aug 2018

Cited by 9 | Viewed by 3665

Abstract

Impaired NO-cGMP signaling has been linked to several neurological disorders. NO-sensitive guanylyl cyclase (NO-GC), of which two isoforms—NO-GC1 and NO-GC2—are known, represents a promising drug target to increase cGMP in the brain. Drug-like small molecules have been discovered that work synergistically with NO to stimulate NO-GC activity. However, the effects of NO-GC stimulators in the brain are not well understood. In the present study, we used Förster/fluorescence resonance energy transfer (FRET)-based real-time imaging of cGMP in acute brain slices and primary neurons of cGMP sensor mice to comparatively assess the activity of two structurally different NO-GC stimulators, IWP-051 and BAY 41-2272, in the cerebellum, striatum and hippocampus. BAY 41-2272 potentiated an elevation of cGMP induced by the NO donor DEA/NO in all tested brain regions. Interestingly, IWP-051 potentiated DEA/NO-induced cGMP increases in the cerebellum and striatum, but not in the hippocampal CA1 area or primary hippocampal neurons. The brain-region-selective activity of IWP-051 suggested that it might act in a NO-GC isoform-selective manner. Results of mRNA in situ hybridization indicated that the cerebellum and striatum express NO-GC1 and NO-GC2, while the hippocampal CA1 area expresses mainly NO-GC2. IWP-051-potentiated DEA/NO-induced cGMP signals in the striatum of NO-GC2 knockout mice but was ineffective in the striatum of NO-GC1 knockout mice. These results indicate that IWP-051 preferentially stimulates NO-GC1 signaling in brain slices. Interestingly, no evidence for an isoform-specific effect of IWP-051 was observed when the cGMP-forming activity of whole brain homogenates was measured. This apparent discrepancy suggests that the method and conditions of cGMP measurement can influence results with NO-GC stimulators. Nevertheless, it is clear that NO-GC stimulators enhance cGMP signaling in the brain and should be further developed for the treatment of neurological diseases. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Graphical abstract

18 pages, 2950 KiB

Open AccessArticle

Real-Time Imaging Reveals Augmentation of Glutamate-Induced Ca²⁺ Transients by the NO-cGMP Pathway in Cerebellar Granule Neurons

by Michael Paolillo, Stefanie Peters, Andrea Schramm, Jens Schlossmann and Robert Feil

Int. J. Mol. Sci. 2018, 19(8), 2185; https://doi.org/10.3390/ijms19082185 - 26 Jul 2018

Cited by 4 | Viewed by 3693

Abstract

Dysfunctions of NO-cGMP signaling have been implicated in various neurological disorders. We have studied the potential crosstalk of cGMP and Ca²⁺ signaling in cerebellar granule neurons (CGNs) by simultaneous real-time imaging of these second messengers in living cells. The NO donor DEA/NO evoked cGMP signals in the granule cell layer of acute cerebellar slices from transgenic mice expressing a cGMP sensor protein. cGMP and Ca²⁺ dynamics were visualized in individual CGNs in primary cultures prepared from 7-day-old cGMP sensor mice. DEA/NO increased the intracellular cGMP concentration and augmented glutamate-induced Ca²⁺ transients. These effects of DEA/NO were absent in CGNs isolated from knockout mice lacking NO-sensitive guanylyl cyclase. Furthermore, application of the cGMP analogues 8-Br-cGMP and 8-pCPT-cGMP, which activate cGMP effector proteins such as cyclic nucleotide-gated cation channels and cGMP-dependent protein kinases (cGKs), also potentiated glutamate-induced Ca²⁺ transients. Western blot analysis failed to detect cGK type I or II in our primary CGNs. The addition of phosphodiesterase (PDE) inhibitors during cGMP imaging showed that CGNs degrade cGMP mainly via Zaprinast-sensitive PDEs, most likely PDE5 and/or PDE10, but not via PDE1, 2, or 3. In sum, these data delineate a cGK-independent NO-cGMP signaling cascade that increases glutamate-induced Ca²⁺ signaling in CGNs. This cGMP–Ca²⁺ crosstalk likely affects neurotransmitter-stimulated functions of CGNs. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Graphical abstract

20 pages, 26911 KiB

Open AccessArticle

Establishing a Split Luciferase Assay for Proteinkinase G (PKG) Interaction Studies

by Andrea Schramm, Philip Mueller-Thuemen, Timo Littmann, Manuela Harloff, Takeaki Ozawa and Jens Schlossmann

Int. J. Mol. Sci. 2018, 19(4), 1180; https://doi.org/10.3390/ijms19041180 - 12 Apr 2018

Cited by 4 | Viewed by 5203

Abstract

Nitric oxide (NO/cyclic guanosine monophosphate (cGMP)-regulated cellular mechanisms are involved in a variety of (patho-) physiological processes. One of the main effector molecules in this system, proteinkinase G (PKG), serves as a molecular switch by phosphorylating different target proteins and thereby turning them on or off. To date, only a few interaction partners of PKG have been described although the identification of protein–protein interactions (PPI) is indispensable for the understanding of cellular processes and diseases. Conventionally used methods to detect PPIs exhibit several disadvantages, e.g., co-immunoprecipitations, which depend on suitable high-affinity antibodies. Therefore, we established a cell-based protein-fragment complementation assay (PCA) for the identification of PKG target proteins. Here, a reporter protein (click beetle luciferase) is split into two fragments and fused to two different possible interaction partners. If interaction occurs, the reporter protein is functionally complemented and the catalyzed reaction can then be quantitatively measured. By using this technique, we confirmed the regulator of G-Protein signaling 2 (RGS2) as an interaction partner of PKGIα (a PKG-isoform) following stimulation with 8-Br-cGMP and 8-pCPT-cGMP. Hence, our results support the conclusion that the established approach could serve as a novel tool for the rapid, easy and cost-efficient detection of novel PKG target proteins. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Graphical abstract

12 pages, 13326 KiB

Open AccessArticle

Impact of the NO-Sensitive Guanylyl Cyclase 1 and 2 on Renal Blood Flow and Systemic Blood Pressure in Mice

by Evanthia Mergia, Manuel Thieme, Henning Hoch, Georgios Daniil, Lydia Hering, Mina Yakoub, Christina Rebecca Scherbaum, Lars Christian Rump, Doris Koesling and Johannes Stegbauer

Int. J. Mol. Sci. 2018, 19(4), 967; https://doi.org/10.3390/ijms19040967 - 23 Mar 2018

Cited by 5 | Viewed by 3406

Abstract

Nitric oxide (NO) modulates renal blood flow (RBF) and kidney function and is involved in blood pressure (BP) regulation predominantly via stimulation of the NO-sensitive guanylyl cyclase (NO-GC), existing in two isoforms, NO-GC1 and NO-GC2. Here, we used isoform-specific knockout (KO) mice and investigated their contribution to renal hemodynamics under normotensive and angiotensin II-induced hypertensive conditions. Stimulation of the NO-GCs by S-nitrosoglutathione (GSNO) reduced BP in normotensive and hypertensive wildtype (WT) and NO-GC2-KO mice more efficiently than in NO-GC1-KO. NO-induced increase of RBF in normotensive mice did not differ between the genotypes, but the respective increase under hypertensive conditions was impaired in NO-GC1-KO. Similarly, inhibition of endogenous NO increased BP and reduced RBF to a lesser extent in NO-GC1-KO than in NO-GC2-KO. These findings indicate NO-GC1 as a target of NO to normalize RBF in hypertension. As these effects were not completely abolished in NO-GC1-KO and renal cyclic guanosine monophosphate (cGMP) levels were decreased in both NO-GC1-KO and NO-GC2-KO, the results suggest an additional contribution of NO-GC2. Hence, NO-GC1 plays a predominant role in the regulation of BP and RBF, especially in hypertension. However, renal NO-GC2 appears to compensate the loss of NO-GC1, and is able to regulate renal hemodynamics under physiological conditions. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Figure 1

21 pages, 2646 KiB

Open AccessArticle

Mathematical Modelling of Nitric Oxide/Cyclic GMP/Cyclic AMP Signalling in Platelets

by Rune Kleppe, Inge Jonassen, Stein Ove Døskeland and Frode Selheim

Int. J. Mol. Sci. 2018, 19(2), 612; https://doi.org/10.3390/ijms19020612 - 19 Feb 2018

Cited by 2 | Viewed by 6035

Abstract

Platelet activation contributes to normal haemostasis but also to pathologic conditions like stroke and cardiac infarction. Signalling by cGMP and cAMP inhibit platelet activation and are therefore attractive targets for thrombosis prevention. However, extensive cross-talk between the cGMP and cAMP signalling pathways in multiple tissues complicates the selective targeting of their activities. We have used mathematical modelling based on experimental data from the literature to quantify the steady state behaviour of nitric oxide (NO)/cGMP/cAMP signalling in platelets. The analysis provides an assessment of NO-induced cGMP synthesis and PKG activation as well as cGMP-mediated cAMP and PKA activation though modulation of phosphodiesterase (PDE2 and 3) activities. Both one- and two-compartment models of platelet cyclic nucleotide signalling are presented. The models provide new insight for understanding how NO signalling to cGMP and indirectly cAMP, can inhibit platelet shape-change, the initial step of platelet activation. Only the two-compartment models could account for the experimental observation that NO-mediated PKA activation can occur when the bulk platelet cAMP level is unchanged. The models revealed also a potential for hierarchical interplay between the different platelet phosphodiesterases. Specifically, the models predict, unexpectedly, a strong effect of pharmacological inhibitors of cGMP-specific PDE5 on the cGMP/cAMP cross-talk. This may explain the successful use of weak PDE5-inhibitors, such as dipyridamole, in anti-platelet therapy. In conclusion, increased NO signalling or PDE5 inhibition are attractive ways of increasing cGMP-cAMP cross-talk selectively in platelets. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Figure 1

3836 KiB

Open AccessArticle

Altered Synaptic Membrane Retrieval after Strong Stimulation of Cerebellar Granule Neurons in Cyclic GMP-Dependent Protein Kinase II (cGKII) Knockout Mice

by Andrea Collado-Alsina, Franz Hofmann, José Sánchez-Prieto and Magdalena Torres

Int. J. Mol. Sci. 2017, 18(11), 2281; https://doi.org/10.3390/ijms18112281 - 30 Oct 2017

Cited by 3 | Viewed by 4954

Abstract

The nitric oxide (NO)/cyclic guanosine monophosphate (cGMP)/cGMP-dependent protein kinase (cGK) signaling pathway regulates the clustering and the recruitment of proteins and vesicles to the synapse, thereby adjusting the exoendocytic cycle to the intensity of activity. Accordingly, this pathway can accelerate endocytosis following large-scale exocytosis, and pre-synaptic cGK type II (cGKII) plays a major role in this process, controlling the homeostatic balance of vesicle exocytosis and endocytosis. We have studied synaptic vesicle recycling in cerebellar granule cells from mice lacking cGKII under strong and sustained stimulation, combining imaging techniques and ultrastructural analyses. The ultrastructure of synapses in the adult mouse cerebellar cortex was also examined in these animals. The lack of cGKII provokes structural changes to synapses in cultured cells and in the cerebellar cortex. Moreover, endocytosis is slowed down in a subset of boutons in these cells when they are stimulated strongly. In addition, from the results obtained with the selective inhibitor of cGKs, KT5823, it can be concluded that cGKI also regulates some aspects of vesicle cycling. Overall, these results confirm the importance of the cGMP pathway in the regulation of vesicle cycling following strong stimulation of cerebellar granule cells. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Graphical abstract

Review

Jump to: Research

18 pages, 1725 KiB

Open AccessReview

The Impact of the Nitric Oxide (NO)/Soluble Guanylyl Cyclase (sGC) Signaling Cascade on Kidney Health and Disease: A Preclinical Perspective

by Shalini M. Krishnan, Jan R. Kraehling, Frank Eitner, Agnès Bénardeau and Peter Sandner

Int. J. Mol. Sci. 2018, 19(6), 1712; https://doi.org/10.3390/ijms19061712 - 09 Jun 2018

Cited by 58 | Viewed by 9397

Abstract

Chronic Kidney Disease (CKD) is a highly prevalent disease with a substantial medical need for new and more efficacious treatments. The Nitric Oxide (NO), soluble guanylyl cyclase (sGC), cyclic guanosine monophosphate (cGMP) signaling cascade regulates various kidney functions. cGMP directly influences renal blood flow, renin secretion, glomerular function, and tubular exchange processes. Downregulation of NO/sGC/cGMP signaling results in severe kidney pathologies such as CKD. Therefore, treatment strategies aiming to maintain or increase cGMP might have beneficial effects for the treatment of progressive kidney diseases. Within this article, we review the NO/sGC/cGMP signaling cascade and its major pharmacological intervention sites. We specifically focus on the currently known effects of cGMP on kidney function parameters. Finally, we summarize the preclinical evidence for kidney protective effects of NO-donors, PDE inhibitors, sGC stimulators, and sGC activators. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Graphical abstract

14 pages, 2711 KiB

Open AccessReview

Molecular Analysis of Sensory Axon Branching Unraveled a cGMP-Dependent Signaling Cascade

by Alexandre Dumoulin, Gohar Ter-Avetisyan, Hannes Schmidt and Fritz G. Rathjen

Int. J. Mol. Sci. 2018, 19(5), 1266; https://doi.org/10.3390/ijms19051266 - 24 Apr 2018

Cited by 12 | Viewed by 5054

Abstract

Axonal branching is a key process in the establishment of circuit connectivity within the nervous system. Molecular-genetic studies have shown that a specific form of axonal branching—the bifurcation of sensory neurons at the transition zone between the peripheral and the central nervous system—is regulated by a cyclic guanosine monophosphate (cGMP)-dependent signaling cascade which is composed of C-type natriuretic peptide (CNP), the receptor guanylyl cyclase Npr2, and cGMP-dependent protein kinase Iα (cGKIα). In the absence of any one of these components, neurons in dorsal root ganglia (DRG) and cranial sensory ganglia no longer bifurcate, and instead turn in either an ascending or a descending direction. In contrast, collateral axonal branch formation which represents a second type of axonal branch formation is not affected by inactivation of CNP, Npr2, or cGKI. Whereas axon bifurcation was lost in mouse mutants deficient for components of CNP-induced cGMP formation; the absence of the cGMP-degrading enzyme phosphodiesterase 2A had no effect on axon bifurcation. Adult mice that lack sensory axon bifurcation due to the conditional inactivation of Npr2-mediated cGMP signaling in DRG neurons demonstrated an altered shape of sensory axon terminal fields in the spinal cord, indicating that elaborate compensatory mechanisms reorganize neuronal circuits in the absence of bifurcation. On a functional level, these mice showed impaired heat sensation and nociception induced by chemical irritants, whereas responses to cold sensation, mechanical stimulation, and motor coordination are normal. These data point to a critical role of axon bifurcation for the processing of acute pain perception. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Graphical abstract

12 pages, 5207 KiB

Open AccessReview

Particulate Guanylyl Cyclase A/cGMP Signaling Pathway in the Kidney: Physiologic and Therapeutic Indications

by Yang Chen and John C. Burnett

Int. J. Mol. Sci. 2018, 19(4), 1006; https://doi.org/10.3390/ijms19041006 - 27 Mar 2018

Cited by 30 | Viewed by 8104

Abstract

The particulate guanylyl cyclase A (pGC-A)/cGMP pathway plays important roles in regulating renal physiological function and as well as in counteracting pathophysiological conditions. Naturally occurring peptide pGC-A activators consist of atrial natriuretic peptide (ANP), b-type NP (BNP), and urodilatin (URO). These activators bind and activate pGC-A, generating the second messenger cyclic 3′,5′ guanosine monophosphate (cGMP). Cyclic GMP binds to downstream pathway effector molecules including protein kinase G (PKG), cGMP-gated ion channels, and phosphodiesterases (PDEs). These mediators result in a variety of physiological actions in the kidney, including diuresis, natriuresis, increased glomerular filtration rate (GFR) and organ protection, thus, opposing renal cellular injury and remodeling. Downstream proteins regulated by PKG include collagen 1 (Col-1), transforming growth factor beta (TGF-β) and apoptosis-related proteins. In addition to their physiological regulatory effects, pGC-A/cGMP signaling is critical for preserving renal homeostasis in different renal diseases such as acute kidney injury (AKI). Regarding therapeutic options, native pGC-A activators have short half-lives and their activity can be further enhanced by advances in innovative peptide engineering. Thus, novel designer peptide pGC-A activators with enhanced renal activity are under development. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Graphical abstract

8 pages, 602 KiB

Open AccessReview

Transepithelial Fluid and Salt Re-Absorption Regulated by cGK2 Signals

by Jianjun Chang, Yan Ding, Zhiyu Zhou, Hong-Guang Nie and Hong-Long Ji

Int. J. Mol. Sci. 2018, 19(3), 881; https://doi.org/10.3390/ijms19030881 - 16 Mar 2018

Cited by 11 | Viewed by 3743

Abstract

Transepithelial fluid and salt re-absorption in epithelial tissues play an important role in fluid and salt homeostasis. In absorptive epithelium, fluid and salt flux is controlled by machinery mainly composed of epithelial sodium channels (ENaC), cystic fibrosis transmembrane conductance regulator (CFTR), Na⁺/H⁺ exchanger (NHE), aquaporin, and sodium potassium adenosine triphosphatase (Na⁺/K⁺-ATPase). Dysregulation of fluid and salt transport across epithelium contributes to the pathogenesis of many diseases, such as pulmonary edema and cystic fibrosis. Intracellular and extracellular signals, i.e., hormones and protein kinases, regulate fluid and salt turnover and resolution. Increasing evidence demonstrates that transepithelial fluid transport is regulated by cyclic guanosine monophosphate-dependent protein kinase (cGK) signals. cGK2 was originally identified and cloned from intestinal specimens, the presence of which has also been confirmed in the kidney and the lung. cGK2 regulates fluid and salt through ENaC, CFTR and NHE. Deficient cGK2 regulation of transepithelial ion transport was seen in acute lung injury, and cGK2 could be a novel druggable target to restore edematous disorder in epithelial tissues. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Figure 1

16 pages, 1047 KiB

Open AccessReview

cGMP Signaling in the Cardiovascular System—The Role of Compartmentation and Its Live Cell Imaging

by Nadja I. Bork and Viacheslav O. Nikolaev

Int. J. Mol. Sci. 2018, 19(3), 801; https://doi.org/10.3390/ijms19030801 - 10 Mar 2018

Cited by 18 | Viewed by 9510

Abstract

The ubiquitous second messenger 3′,5′-cyclic guanosine monophosphate (cGMP) regulates multiple physiologic processes in the cardiovascular system. Its intracellular effects are mediated by stringently controlled subcellular microdomains. In this review, we will illustrate the current techniques available for real-time cGMP measurements with a specific [...] Read more.

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures

Figure 1

15 pages, 2208 KiB

Open AccessReview

Retinal Cyclic Nucleotide-Gated Channels: From Pathophysiology to Therapy

by Stylianos Michalakis, Elvir Becirovic and Martin Biel

Int. J. Mol. Sci. 2018, 19(3), 749; https://doi.org/10.3390/ijms19030749 - 07 Mar 2018

Cited by 56 | Viewed by 8191

Abstract

The first step in vision is the absorption of photons by the photopigments in cone and rod photoreceptors. After initial amplification within the phototransduction cascade the signal is translated into an electrical signal by the action of cyclic nucleotide-gated (CNG) channels. CNG channels are ligand-gated ion channels that are activated by the binding of cyclic guanosine monophosphate (cGMP) or cyclic adenosine monophosphate (cAMP). Retinal CNG channels transduce changes in intracellular concentrations of cGMP into changes of the membrane potential and the Ca²⁺ concentration. Structurally, the CNG channels belong to the superfamily of pore-loop cation channels and share a common gross structure with hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and voltage-gated potassium channels (KCN). In this review, we provide an overview on the molecular properties of CNG channels and describe their physiological role in the phototransduction pathways. We also discuss insights into the pathophysiological role of CNG channel proteins that have emerged from the analysis of CNG channel-deficient animal models and human CNG channelopathies. Finally, we summarize recent gene therapy activities and provide an outlook for future clinical application. Full article

(This article belongs to the Special Issue cGMP-Signalling in Cells: Molecular and Functional Features)

► Show Figures