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Mackiewicz J, Boczek T. A-kinase anchoring protein-mediated compartmentalization of pro-survival signaling in the retina. Neural Regen Res 2025; 20:479-480. [PMID: 38819056 PMCID: PMC11317940 DOI: 10.4103/nrr.nrr-d-24-00168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 03/08/2024] [Accepted: 03/21/2024] [Indexed: 06/01/2024] Open
Affiliation(s)
- Joanna Mackiewicz
- Department of Molecular Neurochemistry, Medical University of Lodz, Lodz, Poland
| | - Tomasz Boczek
- Department of Molecular Neurochemistry, Medical University of Lodz, Lodz, Poland
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2
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Zhu Y, Nair RV, Xia X, Nahmou M, Li X, Yan W, Li J, Tanasa B, Goldberg JL, Kapiloff MS. Reversal of injury-associated retinal ganglion cell gene expression by a phosphodiesterase anchoring disruptor peptide. Exp Eye Res 2024; 246:110017. [PMID: 39097072 PMCID: PMC11330710 DOI: 10.1016/j.exer.2024.110017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 06/24/2024] [Accepted: 07/31/2024] [Indexed: 08/05/2024]
Abstract
Loss of retinal ganglion cells (RGCs) is central to the pathogenesis of optic neuropathies such as glaucoma. Increased RGC cAMP signaling is neuroprotective. We have shown that displacement of the cAMP-specific phosphodiesterase PDE4D3 from an RGC perinuclear compartment by expression of the modified PDE4D3 N-terminal peptide 4D3(E) increases perinuclear cAMP and protein kinase A activity in cultured neurons and in vivo RGC survival after optic nerve crush (ONC) injury. To explore mechanisms by which PDE4D3 displacement promotes neuroprotection, in this study mice intravitreally injected with an adeno-associated virus to express an mCherry-tagged 4D3(E) peptide were subjected to ONC injury and analyzed by single cell RNA-sequencing (scRNA-seq). 4D3(E)-mCherry expression was associated with an attenuation of injury-induced changes in gene expression, thereby supporting the hypothesis that enhanced perinuclear PKA signaling promotes neuroprotective RGC gene expression.
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Affiliation(s)
- Ying Zhu
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, 94034, USA
| | - Ramesh V Nair
- Stanford Center for Genomics and Personalized Medicine, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Xin Xia
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, 94034, USA
| | - Michael Nahmou
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, 94034, USA
| | - Xueyi Li
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, 94034, USA
| | - Wenjun Yan
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, 94034, USA
| | - Jinliang Li
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, 94034, USA
| | - Bogdan Tanasa
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, 94034, USA
| | - Jeffrey L Goldberg
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, 94034, USA
| | - Michael S Kapiloff
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, 94034, USA.
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3
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Taniguchi T, Sharif NA, Ota T, Farjo RA, Rausch R. Assessment of Brain-Derived Neurotrophic Factor on Retinal Structure and Visual Function in Rodent Models of Optic Nerve Crush. Pharmaceuticals (Basel) 2024; 17:798. [PMID: 38931465 PMCID: PMC11206806 DOI: 10.3390/ph17060798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Revised: 06/03/2024] [Accepted: 06/11/2024] [Indexed: 06/28/2024] Open
Abstract
The effects of brain-derived neurotrophic factor (BDNF) on retinal ganglion cell (RGC) survival and visual function were assessed in rat and mouse models of optic nerve (ON) crush. ONs were crushed on Day 1, followed by intravitreal injections of a vehicle or BDNF on Days 1 and 8. The spatial frequency threshold was measured using optokinetic tracking on Days 7 and 14. On Day 15, ganglion cell complex (GCC) thickness was quantified using optical coherence tomography. Furthermore, all eyes were enucleated for immunohistochemical analysis of the surviving RGC somas and axons. BDNF significantly reduced the RGC soma in mice and increased GCC thickness in intact eyes, with apparent axonal swelling in both species. It displayed significantly greater RGC soma survival in eyes with ON injury, with moderately thicker axonal bundles in both species and a thicker GCC in rats. Visual function was significantly reduced in all ON-crushed animals, regardless of BDNF treatment. Thus, we obtained a comprehensive analysis of the structural and functional impact of BDNF in intact and ON-crushed eyes in two rodent models. Our results provide a foundation for further BDNF evaluation and the design of preclinical studies on neuroprotectants using BDNF as a reference positive control.
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Affiliation(s)
- Takazumi Taniguchi
- Ophthalmology Innovation Center, Santen Pharmaceutical Co., Ltd., Nara 630-0101, Japan
| | - Najam A. Sharif
- Ophthalmology Innovation Center, Santen Inc., Emeryville, CA 94608, USA
- Institute of Ophthalmology, University College London, London WC1E 6BT, UK
- Imperial College of Science and Technology, St. Mary’s Campus, London SW7 2AZ, UK
- Eye-APC Duke-NUS Medical School, Singapore 169857, Singapore
- Department of Pharmacy Sciences, Creighton University, Omaha, NE 68178, USA
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, Texas Southern University, Houston, TX 77004, USA
- Department of Pharmacology and Neuroscience, University of North Texas Health Sciences Center, Fort Worth, TX 76107, USA
- Singapore Eye Research Institute, Singapore 169856, Singapore
- Global Research and Development, Nanoscope Therapeutics Inc., Dallas, TX 75207, USA
| | - Takashi Ota
- Ophthalmology Innovation Center, Santen Pharmaceutical Co., Ltd., Nara 630-0101, Japan
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4
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Tomczak J, Mackiewicz J, Lisek M, Kaluza A, Boczek T. Exploring AKAPs in visual signaling. Front Mol Neurosci 2024; 17:1412407. [PMID: 38813437 PMCID: PMC11133604 DOI: 10.3389/fnmol.2024.1412407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 05/02/2024] [Indexed: 05/31/2024] Open
Abstract
The complex nature of the retina demands well-organized signaling to uphold signal accuracy and avoid interference, a critical aspect in handling a variety of visual stimuli. A-kinase anchoring proteins (AKAPs), known for binding protein kinase A (PKA), contribute to the specificity and efficiency of retinal signaling. They play multifaceted roles in various retinal cell types, influencing photoreceptor sensitivity, neurotransmitter release in bipolar cells, and the integration of visual information in ganglion cells. AKAPs like AKAP79/150 and AKAP95 exhibit distinct subcellular localizations, impacting synaptic transmission and receptor sensitivity in photoreceptors and bipolar cells. Furthermore, AKAPs are involved in neuroprotective mechanisms and axonal degeneration, particularly in retinal ganglion cells. In particular, AKAP6 coordinates stress-specific signaling and promotes neuroprotection following optic nerve injury. As our review underscores the therapeutic potential of targeting AKAP signaling complexes for retinal neuroprotection and enhancement, it acknowledges challenges in developing selective drugs that target complex protein-protein interactions. Overall, this exploration of AKAPs provides valuable insights into the intricacies of retinal signaling, offering a foundation for understanding and potentially addressing retinal disorders.
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Affiliation(s)
| | | | | | | | - Tomasz Boczek
- Department of Molecular Neurochemistry, Faculty of Health Sciences, Medical University of Lodz, Lodz, Poland
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5
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Wood EH, Kreymerman A, Kowal T, Buickians D, Sun Y, Muscat S, Mercola M, Moshfeghi DM, Goldberg JL. Cellular and subcellular optogenetic approaches towards neuroprotection and vision restoration. Prog Retin Eye Res 2023; 96:101153. [PMID: 36503723 PMCID: PMC10247900 DOI: 10.1016/j.preteyeres.2022.101153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 11/27/2022] [Accepted: 11/28/2022] [Indexed: 12/13/2022]
Abstract
Optogenetics is defined as the combination of genetic and optical methods to induce or inhibit well-defined events in isolated cells, tissues, or animals. While optogenetics within ophthalmology has been primarily applied towards treating inherited retinal disease, there are a myriad of other applications that hold great promise for a variety of eye diseases including cellular regeneration, modulation of mitochondria and metabolism, regulation of intraocular pressure, and pain control. Supported by primary data from the authors' work with in vitro and in vivo applications, we introduce a novel approach to metabolic regulation, Opsins to Restore Cellular ATP (ORCA). We review the fundamental constructs for ophthalmic optogenetics, present current therapeutic approaches and clinical trials, and discuss the future of subcellular and signaling pathway applications for neuroprotection and vision restoration.
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Affiliation(s)
- Edward H Wood
- Spencer Center for Vision Research, Byers Eye Institute, Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, USA; Stanford Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Alexander Kreymerman
- Spencer Center for Vision Research, Byers Eye Institute, Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, USA; Stanford Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Tia Kowal
- Spencer Center for Vision Research, Byers Eye Institute, Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, USA
| | - David Buickians
- Spencer Center for Vision Research, Byers Eye Institute, Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Yang Sun
- Spencer Center for Vision Research, Byers Eye Institute, Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Stephanie Muscat
- Spencer Center for Vision Research, Byers Eye Institute, Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Mark Mercola
- Stanford Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Darius M Moshfeghi
- Spencer Center for Vision Research, Byers Eye Institute, Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, USA
| | - Jeffrey L Goldberg
- Spencer Center for Vision Research, Byers Eye Institute, Department of Ophthalmology, Stanford University School of Medicine, Palo Alto, CA, USA.
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6
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Erofeeva N, Meshalkina D, Firsov M. Multiple Roles of cAMP in Vertebrate Retina. Cells 2023; 12:cells12081157. [PMID: 37190066 DOI: 10.3390/cells12081157] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/09/2023] [Accepted: 04/10/2023] [Indexed: 05/17/2023] Open
Abstract
cAMP is a key regulatory molecule that controls many important processes in the retina, including phototransduction, cell development and death, growth of neural processes, intercellular contacts, retinomotor effects, and so forth. The total content of cAMP changes in the retina in a circadian manner following the natural light cycle, but it also shows local and even divergent changes in faster time scales in response to local and transient changes in the light environment. Changes in cAMP might also manifest or cause various pathological processes in virtually all cellular components of the retina. Here we review the current state of knowledge and understanding of the regulatory mechanisms by which cAMP influences the physiological processes that occur in various retinal cells.
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Affiliation(s)
- Natalia Erofeeva
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 194223 St. Petersburg, Russia
| | - Darya Meshalkina
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 194223 St. Petersburg, Russia
| | - Michael Firsov
- Sechenov Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, 194223 St. Petersburg, Russia
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7
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Duarte-Silva AT, Ximenes LGR, Guimarães-Souza M, Domith I, Paes-de-Carvalho R. Chemical signaling in the developing avian retina: Focus on cyclic AMP and AKT-dependent pathways. Front Cell Dev Biol 2022; 10:1058925. [PMID: 36568967 PMCID: PMC9780464 DOI: 10.3389/fcell.2022.1058925] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/28/2022] [Indexed: 12/13/2022] Open
Abstract
Communication between developing progenitor cells as well as differentiated neurons and glial cells in the nervous system is made through direct cell contacts and chemical signaling mediated by different molecules. Several of these substances are synthesized and released by developing cells and play roles since early stages of Central Nervous System development. The chicken retina is a very suitable model for neurochemical studies, including the study of regulation of signaling pathways during development. Among advantages of the model are its very well-known histogenesis, the presence of most neurotransmitter systems found in the brain and the possibility to make cultures of neurons and/or glial cells where many neurochemical functions develop in a similar way than in the intact embryonic tissue. In the chicken retina, some neurotransmitters or neuromodulators as dopamine, adenosine, and others are coupled to cyclic AMP production or adenylyl cyclase inhibition since early stages of development. Other substances as vitamin C and nitric oxide are linked to the major neurotransmitter glutamate and AKT metabolism. All these different systems regulate signaling pathways, including PKA, PKG, SRC, AKT and ERK, and the activation of the transcription factor CREB. Dopamine and adenosine stimulate cAMP accumulation in the chick embryo retina through activation of D1 and A2a receptors, respectively, but the onset of dopamine stimulation is much earlier than that of adenosine. However, adenosine can inhibit adenylyl cyclase and modulate dopamine-dependent cAMP increase since early developmental stages through A1 receptors. Dopamine stimulates different PKA as well as EPAC downstream pathways both in intact tissue and in culture as the CSK-SRC pathway modulating glutamate NMDA receptors as well as vitamin C release and CREB phosphorylation. By the other hand, glutamate modulates nitric oxide production and AKT activation in cultured retinal cells and this pathway controls neuronal survival in retina. Glutamate and adenosine stimulate the release of vitamin C and this vitamin regulates the transport of glutamate, activation of NMDA receptors and AKT phosphorylation in cultured retinal cells. In the present review we will focus on these reciprocal interactions between neurotransmitters or neuromodulators and different signaling pathways during retinal development.
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Affiliation(s)
- A. T. Duarte-Silva
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Brazil
| | - L. G. R. Ximenes
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Brazil
| | - M. Guimarães-Souza
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Brazil
| | - I. Domith
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Brazil
| | - R. Paes-de-Carvalho
- Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Brazil,Department of Neurobiology, Institute of Biology, Fluminense Federal University, Niterói, Brazil,*Correspondence: R. Paes-de-Carvalho,
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8
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Levin LA, Patrick C, Choudry NB, Sharif NA, Goldberg JL. Neuroprotection in neurodegenerations of the brain and eye: Lessons from the past and directions for the future. Front Neurol 2022; 13:964197. [PMID: 36034312 PMCID: PMC9412944 DOI: 10.3389/fneur.2022.964197] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 07/20/2022] [Indexed: 12/24/2022] Open
Abstract
Background Neurological and ophthalmological neurodegenerative diseases in large part share underlying biology and pathophysiology. Despite extensive preclinical research on neuroprotection that in many cases bridges and unifies both fields, only a handful of neuroprotective therapies have succeeded clinically in either. Main body Understanding the commonalities among brain and neuroretinal neurodegenerations can help develop innovative ways to improve translational success in neuroprotection research and emerging therapies. To do this, analysis of why translational research in neuroprotection fails necessitates addressing roadblocks at basic research and clinical trial levels. These include optimizing translational approaches with respect to biomarkers, therapeutic targets, treatments, animal models, and regulatory pathways. Conclusion The common features of neurological and ophthalmological neurodegenerations are useful for outlining a path forward that should increase the likelihood of translational success in neuroprotective therapies.
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Affiliation(s)
- Leonard A. Levin
- Departments of Ophthalmology and Visual Sciences, Neurology & Neurosurgery, McGill University, Montreal, QC, Canada
| | | | - Nozhat B. Choudry
- Global Alliances and External Research, Ophthalmology Innovation Center, Santen Inc., Emeryville, CA, United States
| | - Najam A. Sharif
- Global Alliances and External Research, Ophthalmology Innovation Center, Santen Inc., Emeryville, CA, United States
| | - Jeffrey L. Goldberg
- Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, CA, United States
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9
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Shah SH, Schiapparelli LM, Yokota S, Ma Y, Xia X, Shankar S, Saturday S, Nahmou M, Sun C, Yates J, Cline HT, Goldberg JL. Quantitative BONCAT Allows Identification of Newly Synthesized Proteins after Optic Nerve Injury. J Neurosci 2022; 42:4042-4052. [PMID: 35396330 PMCID: PMC9097770 DOI: 10.1523/jneurosci.3100-20.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 02/22/2022] [Accepted: 03/24/2022] [Indexed: 11/21/2022] Open
Abstract
Retinal ganglion cells (RGCs) die after optic nerve trauma or in degenerative disease. However, acute changes in protein expression that may regulate RGC response to injury are not fully understood, and detailed methods to quantify new protein synthesis have not been tested. Here, we develop and apply a new in vivo quantitative measure of newly synthesized proteins to examine changes occurring in the retina after optic nerve injury. Azidohomoalanine, a noncanonical amino acid, was injected intravitreally into the eyes of rodents of either sex with or without optic nerve injury. Isotope variants of biotin-alkyne were used for quantitative BONCAT (QBONCAT) mass spectrometry, allowing identification of protein synthesis and transport rate changes in more than 1000 proteins at 1 or 5 d after optic nerve injury. In vitro screening showed several newly synthesized proteins regulate axon outgrowth in primary neurons in vitro This novel approach to targeted quantification of newly synthesized proteins after injury uncovers a dynamic translational response within broader proteostasis regulation and enhances our understanding of the cellular response to injury.SIGNIFICANCE STATEMENT Optic nerve injury results in death and degeneration of retinal ganglion cells and their axons. The specific cellular response to injury, including changes in new protein synthesis, is obscured by existing proteins and protein degradation. In this study, we introduce QBONCAT to isolate and quantify acute protein synthesis and subsequent transport between cellular compartments. We identify novel candidate protein effectors of the regenerative response and uncover their regulation of axon growth in vitro, validating the utility of QBONCAT for the discovery of novel regulatory and therapeutic candidates after optic nerve injury.
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Affiliation(s)
- Sahil H Shah
- Mary M. and Sash A. Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, California 94303
- Neuroscience Department and Dorris Neuroscience Center, Scripps Research, La Jolla, California 92093
- Neurosciences Graduate Program and Medical Scientist Training Program, University of California, San Diego, La Jolla, California 92093
| | - Lucio M Schiapparelli
- Neuroscience Department and Dorris Neuroscience Center, Scripps Research, La Jolla, California 92093
- Department of Cell Biology, Duke University Medical School, Durham, North Carolina, 27708
| | - Satoshi Yokota
- Mary M. and Sash A. Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, California 94303
| | - Yuanhui Ma
- Department of Molecular Medicine, Scripps Research, La Jolla, California 92093
| | - Xin Xia
- Mary M. and Sash A. Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, California 94303
| | - Sahana Shankar
- Mary M. and Sash A. Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, California 94303
| | - Sarah Saturday
- Neuroscience Department and Dorris Neuroscience Center, Scripps Research, La Jolla, California 92093
| | - Michael Nahmou
- Mary M. and Sash A. Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, California 94303
| | - Catalina Sun
- Mary M. and Sash A. Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, California 94303
| | - John Yates
- Department of Molecular Medicine, Scripps Research, La Jolla, California 92093
| | - Hollis T Cline
- Neuroscience Department and Dorris Neuroscience Center, Scripps Research, La Jolla, California 92093
| | - Jeffrey L Goldberg
- Mary M. and Sash A. Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, California 94303
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10
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Shah SH, Schiapparelli LM, Ma Y, Yokota S, Atkins M, Xia X, Cameron EG, Huang T, Saturday S, Sun CB, Knasel C, Blackshaw S, Yates Iii JR, Cline HT, Goldberg JL. Quantitative transportomics identifies Kif5a as a major regulator of neurodegeneration. eLife 2022; 11:68148. [PMID: 35259089 PMCID: PMC8947766 DOI: 10.7554/elife.68148] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 03/07/2022] [Indexed: 11/29/2022] Open
Abstract
Many neurons in the adult central nervous system, including retinal ganglion cells (RGCs), degenerate and die after injury. Early axon protein and organelle trafficking failure is a key component in many neurodegenerative disorders yet changes to axoplasmic transport in disease models have not been quantified. We analyzed early changes in the protein ‘transportome’ from RGC somas to their axons after optic nerve injury and identified transport failure of an anterograde motor protein Kif5a early in RGC degeneration. We demonstrated that manipulating Kif5a expression affects anterograde mitochondrial trafficking in RGCs and characterized axon transport in Kif5a knockout mice to identify proteins whose axon localization was Kif5a-dependent. Finally, we found that knockout of Kif5a in RGCs resulted in progressive RGC degeneration in the absence of injury. Together with expression data localizing Kif5a to human RGCs, these data identify Kif5a transport failure as a cause of RGC neurodegeneration and point to a mechanism for future therapeutics.
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Affiliation(s)
- Sahil H Shah
- Byers Eye Institute and Spencer Center for Vision Research, Stanford University, Palo Alto, United States
| | | | - Yuanhui Ma
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, United States
| | - Satoshi Yokota
- Byers Eye Institute and Spencer Center for Vision Research, Stanford University, Palo Alto, United States
| | - Melissa Atkins
- Byers Eye Institute and Spencer Center for Vision Research, Stanford University, Palo Alto, United States
| | - Xin Xia
- Byers Eye Institute and Spencer Center for Vision Research, Stanford University, Palo Alto, United States
| | - Evan G Cameron
- Byers Eye Institute and Spencer Center for Vision Research, Stanford University, Palo Alto, United States
| | - Thanh Huang
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Sarah Saturday
- Neuroscience Department, The Scripps Research Institute, La Jolla, United States
| | - Catalin B Sun
- Byers Eye Institute and Spencer Center for Vision Research, Stanford University, Palo Alto, United States
| | - Cara Knasel
- Byers Eye Institute and Spencer Center for Vision Research, Stanford University, Palo Alto, United States
| | - Seth Blackshaw
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - John R Yates Iii
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, United States
| | - Hollis T Cline
- Neuroscience Department, The Scripps Research Institute, La Jolla, United States
| | - Jeffrey L Goldberg
- Byers Eye Institute and Spencer Center for Vision Research, Stanford University, Palo Alto, United States
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11
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Abstract
The damage or loss of retinal ganglion cells (RGCs) and their axons accounts for the visual functional defects observed after traumatic injury, in degenerative diseases such as glaucoma, or in compressive optic neuropathies such as from optic glioma. By using optic nerve crush injury models, recent studies have revealed the cellular and molecular logic behind the regenerative failure of injured RGC axons in adult mammals and suggested several strategies with translational potential. This review summarizes these findings and discusses challenges for developing clinically applicable neural repair strategies.
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Affiliation(s)
- Philip R Williams
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Larry I Benowitz
- Laboratories for Neuroscience Research in Neurosurgery, Boston Children's Hospital, Boston, Massachusetts 02115, USA.,F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, Massachusetts 02115, USA; .,Department of Neurosurgery, Harvard Medical School, Boston, Massachusetts 02115, USA.,Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Jeffrey L Goldberg
- Spencer Center for Vision Research, Byers Eye Institute, Stanford University, Palo Alto, California 94303, USA
| | - Zhigang He
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, Massachusetts 02115, USA; .,Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts 02115, USA.,Department of Neurology, Harvard Medical School, Boston, Massachusetts 02115, USA
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12
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Potential therapeutic applications of AKAP disrupting peptides. Clin Sci (Lond) 2021; 134:3259-3282. [PMID: 33346357 DOI: 10.1042/cs20201244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/16/2020] [Accepted: 11/30/2020] [Indexed: 11/17/2022]
Abstract
The 3'-5'-cyclic adenosine monophosphate (cAMP)/PKA pathway represents a major target for pharmacological intervention in multiple disease conditions. Although the last decade saw the concept of highly compartmentalized cAMP/PKA signaling consolidating, current means for the manipulation of this pathway still do not allow to specifically intervene on discrete cAMP/PKA microdomains. Since compartmentalization is crucial for action specificity, identifying new tools that allow local modulation of cAMP/PKA responses is an urgent need. Among key players of cAMP/PKA signaling compartmentalization, a major role is played by A-kinase anchoring proteins (AKAPs) that, by definition, anchor PKA, its substrates and its regulators within multiprotein complexes in well-confined subcellular compartments. Different tools have been conceived to interfere with AKAP-based protein-protein interactions (PPIs), and these primarily include peptides and peptidomimetics that disrupt AKAP-directed multiprotein complexes. While these molecules have been extensively used to understand the molecular mechanisms behind AKAP function in pathophysiological processes, less attention has been devoted to their potential application for therapy. In this review, we will discuss how AKAP-based PPIs can be pharmacologically targeted by synthetic peptides and peptidomimetics.
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13
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cAMP at Perinuclear mAKAPα Signalosomes Is Regulated by Local Ca 2+ Signaling in Primary Hippocampal Neurons. eNeuro 2021; 8:ENEURO.0298-20.2021. [PMID: 33495246 PMCID: PMC7920539 DOI: 10.1523/eneuro.0298-20.2021] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 01/07/2021] [Accepted: 01/10/2021] [Indexed: 12/14/2022] Open
Abstract
The second messenger cyclic adenosine monophosphate (cAMP) is important for the regulation of neuronal structure and function, including neurite extension. A perinuclear cAMP compartment organized by the scaffold protein muscle A-kinase anchoring protein α (mAKAPα/AKAP6α) is sufficient and necessary for axon growth by rat hippocampal neurons in vitro. Here, we report that cAMP at mAKAPα signalosomes is regulated by local Ca2+ signaling that mediates activity-dependent cAMP elevation within that compartment. Simultaneous Forster resonance energy transfer (FRET) imaging using the protein kinase A (PKA) activity reporter AKAR4 and intensiometric imaging using the RCaMP1h fluorescent Ca2+ sensor revealed that membrane depolarization by KCl selectively induced activation of perinuclear PKA activity. Activity-dependent perinuclear PKA activity was dependent on expression of the mAKAPα scaffold, while both perinuclear Ca2+ elevation and PKA activation were dependent on voltage-dependent L-type Ca2+ channel activity. Importantly, chelation of Ca2+ by a nuclear envelope-localized parvalbumin fusion protein inhibited both activity-induced perinuclear PKA activity and axon elongation. Together, this study provides evidence for a model in which a neuronal perinuclear cAMP compartment is locally regulated by activity-dependent Ca2+ influx, providing local control for the enhancement of neurite extension.
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Xia X, Yu CY, Bian M, Sun CB, Tanasa B, Chang KC, Bruffett DM, Thakur H, Shah SH, Knasel C, Cameron EG, Kapiloff MS, Goldberg JL. MEF2 transcription factors differentially contribute to retinal ganglion cell loss after optic nerve injury. PLoS One 2020; 15:e0242884. [PMID: 33315889 PMCID: PMC7735573 DOI: 10.1371/journal.pone.0242884] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 11/10/2020] [Indexed: 02/07/2023] Open
Abstract
Loss of retinal ganglion cells (RGCs) in optic neuropathies results in permanent partial or complete blindness. Myocyte enhancer factor 2 (MEF2) transcription factors have been shown to play a pivotal role in neuronal systems, and in particular MEF2A knockout was shown to enhance RGC survival after optic nerve crush injury. Here we expanded these prior data to study bi-allelic, tri-allelic and heterozygous allele deletion. We observed that deletion of all MEF2A, MEF2C, and MEF2D alleles had no effect on RGC survival during development. Our extended experiments suggest that the majority of the neuroprotective effect was conferred by complete deletion of MEF2A but that MEF2D knockout, although not sufficient to increase RGC survival on its own, increased the positive effect of MEF2A knockout. Conversely, MEF2A over-expression in wildtype mice worsened RGC survival after optic nerve crush. Interestingly, MEF2 transcription factors are regulated by post-translational modification, including by calcineurin-catalyzed dephosphorylation of MEF2A Ser-408 known to increase MEF2A-dependent transactivation in neurons. However, neither phospho-mimetic nor phospho-ablative mutation of MEF2A Ser-408 affected the ability of MEF2A to promote RGC death in vivo after optic nerve injury. Together these findings demonstrate that MEF2 gene expression opposes RGC survival following axon injury in a complex hierarchy, and further support the hypothesis that loss of or interference with MEF2A expression might be beneficial for RGC neuroprotection in diseases such as glaucoma and other optic neuropathies.
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Affiliation(s)
- Xin Xia
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Caroline Y. Yu
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Minjuan Bian
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Catalina B. Sun
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Bogdan Tanasa
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Kun-Che Chang
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Dawn M. Bruffett
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Hrishikesh Thakur
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Sahil H. Shah
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Cara Knasel
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Evan G. Cameron
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
| | - Michael S. Kapiloff
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
- Department of Medicine and Stanford Cardiovascular Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
- * E-mail: (MSK); (JLG)
| | - Jeffrey L. Goldberg
- Mary M. and Sash A. Spencer Center for Vision Research, Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine, Palo Alto, CA, United States of America
- * E-mail: (MSK); (JLG)
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Boczek T, Kapiloff MS. Compartmentalization of local cAMP signaling in neuronal growth and survival. Neural Regen Res 2019; 15:453-454. [PMID: 31571655 PMCID: PMC6921356 DOI: 10.4103/1673-5374.266055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- Tomasz Boczek
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, USA; Department of Molecular Neurochemistry, Medical University of Lodz, Poland
| | - Michael S Kapiloff
- Department of Ophthalmology, Byers Eye Institute, Mary M. and Sash A. Spencer Center for Vision Research, Stanford University School of Medicine, Palo Alto, CA, USA
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Dodge-Kafka K, Gildart M, Tokarski K, Kapiloff MS. mAKAPβ signalosomes - A nodal regulator of gene transcription associated with pathological cardiac remodeling. Cell Signal 2019; 63:109357. [PMID: 31299211 PMCID: PMC7197268 DOI: 10.1016/j.cellsig.2019.109357] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 07/01/2019] [Accepted: 07/05/2019] [Indexed: 12/14/2022]
Abstract
Striated myocytes compose about half of the cells of the heart, while contributing the majority of the heart's mass and volume. In response to increased demands for pumping power, including in diseases of pressure and volume overload, the contractile myocytes undergo non-mitotic growth, resulting in increased heart mass, i.e. cardiac hypertrophy. Myocyte hypertrophy is induced by a change in the gene expression program driven by the altered activity of transcription factors and co-repressor and co-activator chromatin-associated proteins. These gene regulatory proteins are subject to diverse post-translational modifications and serve as nuclear effectors for intracellular signal transduction pathways, including those controlled by cyclic nucleotides and calcium ion. Scaffold proteins contribute to the underlying architecture of intracellular signaling networks by targeting signaling enzymes to discrete intracellular compartments, providing specificity to the regulation of downstream effectors, including those regulating gene expression. Muscle A-kinase anchoring protein β (mAKAPβ) is a well-characterized scaffold protein that contributes to the regulation of pathological cardiac hypertrophy. In this review, we discuss the mechanisms how this prototypical scaffold protein organizes signalosomes responsible for the regulation of class IIa histone deacetylases and cardiac transcription factors such as NFAT, MEF2, and HIF-1α, as well as how this signalosome represents a novel therapeutic target for the prevention or treatment of heart failure.
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Affiliation(s)
- Kimberly Dodge-Kafka
- Calhoun Center for Cardiology, Cardiac Signal Transduction and Cellular Biology Laboratory, University of Connecticut Health Center, Farmington, CT, USA.
| | - Moriah Gildart
- Calhoun Center for Cardiology, Cardiac Signal Transduction and Cellular Biology Laboratory, University of Connecticut Health Center, Farmington, CT, USA
| | - Kristin Tokarski
- Calhoun Center for Cardiology, Cardiac Signal Transduction and Cellular Biology Laboratory, University of Connecticut Health Center, Farmington, CT, USA
| | - Michael S Kapiloff
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute, Stanford University, Palo Alto, CA, USA
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Regulation of Neuronal Survival and Axon Growth by a Perinuclear cAMP Compartment. J Neurosci 2019; 39:5466-5480. [PMID: 31097623 DOI: 10.1523/jneurosci.2752-18.2019] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 03/11/2019] [Accepted: 04/10/2019] [Indexed: 12/21/2022] Open
Abstract
cAMP signaling is known to be critical in neuronal survival and axon growth. Increasingly the subcellular compartmentation of cAMP signaling has been appreciated, but outside of dendritic synaptic regulation, few cAMP compartments have been defined in terms of molecular composition or function in neurons. Specificity in cAMP signaling is conferred in large part by A-kinase anchoring proteins (AKAPs) that localize protein kinase A and other signaling enzymes to discrete intracellular compartments. We now reveal that cAMP signaling within a perinuclear neuronal compartment organized by the large multivalent scaffold protein mAKAPα promotes neuronal survival and axon growth. mAKAPα signalosome function is explored using new molecular tools designed to specifically alter local cAMP levels as studied by live-cell FRET imaging. In addition, enhancement of mAKAPα-associated cAMP signaling by isoform-specific displacement of bound phosphodiesterase is demonstrated to increase retinal ganglion cell survival in vivo in mice of both sexes following optic nerve crush injury. These findings define a novel neuronal compartment that confers cAMP regulation of neuroprotection and axon growth and that may be therapeutically targeted in disease.SIGNIFICANCE STATEMENT cAMP is a second messenger responsible for the regulation of diverse cellular processes including neuronal neurite extension and survival following injury. Signal transduction by cAMP is highly compartmentalized in large part because of the formation of discrete, localized multimolecular signaling complexes by A-kinase anchoring proteins. Although the concept of cAMP compartmentation is well established, the function and identity of these compartments remain poorly understood in neurons. In this study, we provide evidence for a neuronal perinuclear cAMP compartment organized by the scaffold protein mAKAPα that is necessary and sufficient for the induction of neurite outgrowth in vitro and for the survival of retinal ganglion cells in vivo following optic nerve injury.
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Dodge-Kafka KL, Gildart M, Li J, Thakur H, Kapiloff MS. Bidirectional regulation of HDAC5 by mAKAPβ signalosomes in cardiac myocytes. J Mol Cell Cardiol 2018. [PMID: 29522762 DOI: 10.1016/j.yjmcc.2018.03.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Class IIa histone deacetylases (HDACs) are transcriptional repressors whose nuclear export in the cardiac myocyte is associated with the induction of pathological gene expression and cardiac remodeling. Class IIa HDACs are regulated by multiple, functionally opposing post-translational modifications, including phosphorylation by protein kinase D (PKD) that promotes nuclear export and phosphorylation by protein kinase A (PKA) that promotes nuclear import. We have previously shown that the scaffold protein muscle A-kinase anchoring protein β (mAKAPβ) orchestrates signaling in the cardiac myocyte required for pathological cardiac remodeling, including serving as a scaffold for both PKD and PKA. We now show that mAKAPβ is a scaffold for HDAC5 in cardiac myocytes, forming signalosomes containing HDAC5, PKD, and PKA. Inhibition of mAKAPβ expression attenuated the phosphorylation of HDAC5 by PKD and PKA in response to α- and β-adrenergic receptor stimulation, respectively. Importantly, disruption of mAKAPβ-HDAC5 anchoring prevented the induction of HDAC5 nuclear export by α-adrenergic receptor signaling and PKD phosphorylation. In addition, disruption of mAKAPβ-PKA anchoring prevented the inhibition by β-adrenergic receptor stimulation of α-adrenergic-induced HDAC5 nuclear export. Together, these data establish that mAKAPβ signalosomes serve to bidirectionally regulate the nuclear-cytoplasmic localization of class IIa HDACs. Thus, the mAKAPβ scaffold serves as a node in the myocyte regulatory network controlling both the repression and activation of pathological gene expression in health and disease, respectively.
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Affiliation(s)
- Kimberly L Dodge-Kafka
- Calhoun Center for Cardiology, University of Connecticut Health Center, Cardiac Signal Transduction and Cellular Biology Laboratory, Farmington, CT, USA.
| | - Moriah Gildart
- Calhoun Center for Cardiology, University of Connecticut Health Center, Cardiac Signal Transduction and Cellular Biology Laboratory, Farmington, CT, USA
| | - Jinliang Li
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute Stanford University, Palo Alto, CA, USA
| | - Hrishikesh Thakur
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute Stanford University, Palo Alto, CA, USA
| | - Michael S Kapiloff
- Departments of Ophthalmology and Medicine, Stanford Cardiovascular Institute Stanford University, Palo Alto, CA, USA.
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Wild AR, Dell'Acqua ML. Potential for therapeutic targeting of AKAP signaling complexes in nervous system disorders. Pharmacol Ther 2017; 185:99-121. [PMID: 29262295 DOI: 10.1016/j.pharmthera.2017.12.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A common feature of neurological and neuropsychiatric disorders is a breakdown in the integrity of intracellular signal transduction pathways. Dysregulation of ion channels and receptors in the cell membrane and the enzymatic mediators that link them to intracellular effectors can lead to synaptic dysfunction and neuronal death. However, therapeutic targeting of these ubiquitous signaling elements can lead to off-target side effects due to their widespread expression in multiple systems of the body. A-kinase anchoring proteins (AKAPs) are multivalent scaffolding proteins that compartmentalize a diverse range of receptor and effector proteins to streamline signaling within nanodomain signalosomes. A number of essential neurological processes are known to critically depend on AKAP-directed signaling and an understanding of the role AKAPs play in nervous system disorders has emerged in recent years. Selective targeting of AKAP protein-protein interactions may be a means to uncouple pathologically active signaling pathways in neurological disorders with a greater degree of specificity. In this review we will discuss the role of AKAPs in both regulating normal nervous system function and dysfunction associated with disease, and the potential for therapeutic targeting of AKAP signaling complexes.
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Affiliation(s)
- Angela R Wild
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Mark L Dell'Acqua
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO 80045, USA.
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20
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Gorshkov K, Mehta S, Ramamurthy S, Ronnett GV, Zhou FQ, Zhang J. AKAP-mediated feedback control of cAMP gradients in developing hippocampal neurons. Nat Chem Biol 2017; 13:425-431. [PMID: 28192412 PMCID: PMC5362298 DOI: 10.1038/nchembio.2298] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 12/06/2016] [Indexed: 01/06/2023]
Abstract
Cyclic AMP (cAMP) and protein kinase A (PKA), classical examples of spatially compartmentalized signaling molecules, are critical axon determinants that regulate neuronal polarity and axon formation, yet little is known about micro-compartmentalization of cAMP and PKA signaling and its role in developing neurons. Here, we revealed that cAMP forms a gradient in developing hippocampal neurons, with higher cAMP levels in more distal regions of the axon compared to other regions of the cell. Interestingly, this cAMP gradient changed according to the developmental stage and depended on proper anchoring of PKA by A-kinase anchoring proteins (AKAPs). Disrupting PKA anchoring to AKAPs increased the cAMP gradient in early-stage neurons and led to enhanced axon elongation. Our results provide new evidence for a local negative feedback loop, assembled by AKAPs, for the precise control of a growth-stage-dependent cAMP gradient to ensure proper axon growth.
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Affiliation(s)
- Kirill Gorshkov
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Pharmacology, University of California, San Diego, La Jolla, California, USA
| | - Sohum Mehta
- Department of Pharmacology, University of California, San Diego, La Jolla, California, USA
| | - Santosh Ramamurthy
- Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Center for Metabolism and Obesity Research, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Gabriele V Ronnett
- Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Center for Metabolism and Obesity Research, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Departments of Neurology and Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Feng-Quan Zhou
- Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Orthopedic Surgery, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jin Zhang
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Pharmacology, University of California, San Diego, La Jolla, California, USA
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21
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Cameron EG, Kapiloff MS. Intracellular compartmentation of cAMP promotes neuroprotection and regeneration of CNS neurons. Neural Regen Res 2017; 12:201-202. [PMID: 28400794 PMCID: PMC5361496 DOI: 10.4103/1673-5374.200797] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Evan G Cameron
- Byers Eye Institute, Stanford University, Palo Alto, CA, USA
| | - Michael S Kapiloff
- Department of Pediatrics and Medicine, Leonard M. Miller School of Medicine, University of Miami, Miami, FL, USA
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