1
|
Ando F, Hara Y, Uchida S. Identification of protein kinase A signalling molecules in renal collecting ducts. J Physiol 2024; 602:3057-3067. [PMID: 37013848 DOI: 10.1113/jp284178] [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: 01/27/2023] [Accepted: 03/31/2023] [Indexed: 04/05/2023] Open
Abstract
Body water homeostasis is maintained by the correct balance between water intake and water loss through urine, faeces, sweat and breath. It is known that elevated circulating levels of the antidiuretic hormone vasopressin decrease urine volume to prevent excessive water loss from the body. Vasopressin/cAMP/protein kinase A (PKA) signalling is the canonical pathway in renal collecting ducts for phosphorylating aquaporin-2 (AQP2) water channels, which leads to the reabsorption of water from urine via AQP2. Although recent omics data have verified various downstream targets of PKA, crucial regulators that mediate PKA-induced AQP2 phosphorylation remain unknown, mainly because vasopressin is usually used to activate PKA as a positive control. Vasopressin is extremely potent and phosphorylates various PKA substrates non-specifically, making it difficult to narrow down the candidate mediators responsible for AQP2 phosphorylation. The intracellular localization of PKA is tightly regulated by its scaffold proteins, also known as A-kinase anchoring proteins (AKAPs). Furthermore, each AKAP has a target domain that determines its intracellular localization, enabling the creation of a local PKA signalling network. Although vasopressin activates most PKAs independently of their intracellular localization, some chemical compounds preferentially act on PKAs localized on AQP2-containing vesicles while simultaneously phosphorylating AQP2 and its surrounding PKA substrates. Immunoprecipitation with antibodies against phosphorylated PKA substrates followed by mass spectrometry analysis revealed that the PKA substrate in proximity to AQP2 was lipopolysaccharide-responsive and beige-like anchor (LRBA). Furthermore, Lrba knockout studies revealed that LRBA was required for vasopressin-induced AQP2 phosphorylation.
Collapse
Affiliation(s)
- Fumiaki Ando
- Department of Nephrology, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Yu Hara
- Department of Nephrology, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| | - Shinichi Uchida
- Department of Nephrology, Tokyo Medical and Dental University (TMDU), Tokyo, Japan
| |
Collapse
|
2
|
Kharin A, Klussmann E. Many kinases for controlling the water channel aquaporin-2. J Physiol 2024; 602:3025-3039. [PMID: 37440212 DOI: 10.1113/jp284100] [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: 03/29/2023] [Accepted: 06/26/2023] [Indexed: 07/14/2023] Open
Abstract
Aquaporin-2 (AQP2) is a member of the aquaporin water channel family. In the kidney, AQP2 is expressed in collecting duct principal cells where it facilitates water reabsorption in response to antidiuretic hormone (arginine vasopressin, AVP). AVP induces the redistribution of AQP2 from intracellular vesicles and its incorporation into the plasma membrane. The plasma membrane insertion of AQP2 represents the crucial step in AVP-mediated water reabsorption. Dysregulation of the system preventing the AQP2 plasma membrane insertion causes diabetes insipidus (DI), a disease characterised by an impaired urine concentrating ability and polydipsia. There is no satisfactory treatment of DI available. This review discusses kinases that control the localisation of AQP2 and points out potential kinase-directed targets for the treatment of DI.
Collapse
Affiliation(s)
- Andrii Kharin
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Enno Klussmann
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
- DZHK (German Center for Cardiovascular Research), Berlin, Germany
| |
Collapse
|
3
|
Donders Z, Skorupska IJ, Willems E, Mussen F, Broeckhoven JV, Carlier A, Schepers M, Vanmierlo T. Beyond PDE4 inhibition: A comprehensive review on downstream cAMP signaling in the central nervous system. Biomed Pharmacother 2024; 177:117009. [PMID: 38908196 DOI: 10.1016/j.biopha.2024.117009] [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: 03/28/2024] [Revised: 05/27/2024] [Accepted: 06/17/2024] [Indexed: 06/24/2024] Open
Abstract
Cyclic adenosine monophosphate (cAMP) is a key second messenger that regulates signal transduction pathways pivotal for numerous biological functions. Intracellular cAMP levels are spatiotemporally regulated by their hydrolyzing enzymes called phosphodiesterases (PDEs). It has been shown that increased cAMP levels in the central nervous system (CNS) promote neuroplasticity, neurotransmission, neuronal survival, and myelination while suppressing neuroinflammation. Thus, elevating cAMP levels through PDE inhibition provides a therapeutic approach for multiple CNS disorders, including multiple sclerosis, stroke, spinal cord injury, amyotrophic lateral sclerosis, traumatic brain injury, and Alzheimer's disease. In particular, inhibition of the cAMP-specific PDE4 subfamily is widely studied because of its high expression in the CNS. So far, the clinical translation of full PDE4 inhibitors has been hampered because of dose-limiting side effects. Hence, focusing on signaling cascades downstream activated upon PDE4 inhibition presents a promising strategy, offering novel and pharmacologically safe targets for treating CNS disorders. Yet, the underlying downstream signaling pathways activated upon PDE(4) inhibition remain partially elusive. This review provides a comprehensive overview of the existing knowledge regarding downstream mediators of cAMP signaling induced by PDE4 inhibition or cAMP stimulators. Furthermore, we highlight existing gaps and future perspectives that may incentivize additional downstream research concerning PDE(4) inhibition, thereby providing novel therapeutic approaches for CNS disorders.
Collapse
Affiliation(s)
- Zoë Donders
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht 6229ER, the Netherlands; Department of Neuroscience, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt 3500, Belgium
| | - Iga Joanna Skorupska
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht 6229ER, the Netherlands; Department of Neuroscience, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt 3500, Belgium; Department of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht 6629ER, the Netherlands
| | - Emily Willems
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht 6229ER, the Netherlands; Department of Neuroscience, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt 3500, Belgium
| | - Femke Mussen
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht 6229ER, the Netherlands; Department of Neuroscience, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt 3500, Belgium; Department of Immunology and Infection, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt 3500, Belgium
| | - Jana Van Broeckhoven
- Department of Immunology and Infection, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt 3500, Belgium; University MS Centre (UMSC) Hasselt - Pelt, Belgium
| | - Aurélie Carlier
- Department of Cell Biology-Inspired Tissue Engineering, MERLN Institute for Technology-Inspired Regenerative Medicine, Maastricht 6629ER, the Netherlands
| | - Melissa Schepers
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht 6229ER, the Netherlands; Department of Neuroscience, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt 3500, Belgium; University MS Centre (UMSC) Hasselt - Pelt, Belgium
| | - Tim Vanmierlo
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht 6229ER, the Netherlands; Department of Neuroscience, Biomedical Research Institute, Faculty of Medicine and Life Sciences, Hasselt University, Hasselt 3500, Belgium; University MS Centre (UMSC) Hasselt - Pelt, Belgium.
| |
Collapse
|
4
|
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.
Collapse
Affiliation(s)
| | | | | | | | - Tomasz Boczek
- Department of Molecular Neurochemistry, Faculty of Health Sciences, Medical University of Lodz, Lodz, Poland
| |
Collapse
|
5
|
Feichtner A, Enzler F, Kugler V, Hoppe K, Mair S, Kremser L, Lindner H, Huber RG, Stelzl U, Stefan E, Torres-Quesada O. Phosphorylation of the compartmentalized PKA substrate TAF15 regulates RNA-protein interactions. Cell Mol Life Sci 2024; 81:162. [PMID: 38568213 PMCID: PMC10991009 DOI: 10.1007/s00018-024-05204-4] [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: 08/18/2023] [Revised: 03/08/2024] [Accepted: 03/09/2024] [Indexed: 04/05/2024]
Abstract
Spatiotemporal-controlled second messengers alter molecular interactions of central signaling nodes for ensuring physiological signal transmission. One prototypical second messenger molecule which modulates kinase signal transmission is the cyclic-adenosine monophosphate (cAMP). The main proteinogenic cellular effectors of cAMP are compartmentalized protein kinase A (PKA) complexes. Their cell-type specific compositions precisely coordinate substrate phosphorylation and proper signal propagation which is indispensable for numerous cell-type specific functions. Here we present evidence that TAF15, which is implicated in the etiology of amyotrophic lateral sclerosis, represents a novel nuclear PKA substrate. In cross-linking and immunoprecipitation experiments (iCLIP) we showed that TAF15 phosphorylation alters the binding to target transcripts related to mRNA maturation, splicing and protein-binding related functions. TAF15 appears to be one of multiple PKA substrates that undergo RNA-binding dynamics upon phosphorylation. We observed that the activation of the cAMP-PKA signaling axis caused a change in the composition of a collection of RNA species that interact with TAF15. This observation appears to be a broader principle in the regulation of molecular interactions, as we identified a significant enrichment of RNA-binding proteins within endogenous PKA complexes. We assume that phosphorylation of RNA-binding domains adds another layer of regulation to binary protein-RNAs interactions with consequences to RNA features including binding specificities, localization, abundance and composition.
Collapse
Affiliation(s)
- Andreas Feichtner
- Tyrolean Cancer Research Institute (TKFI), Innrain 66, 6020, Innsbruck, Austria
- Institute of Molecular Biology and Center for Molecular Biosciences, University of Innsbruck, Technikerstrasse 25, 6020, Innsbruck, Austria
| | - Florian Enzler
- Daniel Swarovski Research Laboratory, Department of Visceral, Transplant and Thoracic Surgery, Medical University of Innsbruck, Innrain 66/66a, 6020, Innsbruck, Austria
| | - Valentina Kugler
- Tyrolean Cancer Research Institute (TKFI), Innrain 66, 6020, Innsbruck, Austria
- Institute of Molecular Biology and Center for Molecular Biosciences, University of Innsbruck, Technikerstrasse 25, 6020, Innsbruck, Austria
| | - Katharina Hoppe
- Institute of Developmental Immunology, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020, Innsbruck, Austria
| | - Sophia Mair
- Department of Cardiac Surgery, Medical University of Innsbruck, Innrain 66/66a, 6020, Innsbruck, Austria
- Vascage, Center of Clinical Stroke Research, 6020, Innsbruck, Austria
| | - Leopold Kremser
- Division of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020, Innsbruck, Austria
| | - Herbert Lindner
- Division of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020, Innsbruck, Austria
| | - Roland G Huber
- Bioinformatics Institute, Agency for Science Technology and Research, Singapore, 138671, Singapore
| | - Ulrich Stelzl
- Institute of Pharmaceutical Sciences, University of Graz, Schubertstrasse 1, 8010, Graz, Austria
| | - Eduard Stefan
- Tyrolean Cancer Research Institute (TKFI), Innrain 66, 6020, Innsbruck, Austria.
- Institute of Molecular Biology and Center for Molecular Biosciences, University of Innsbruck, Technikerstrasse 25, 6020, Innsbruck, Austria.
| | - Omar Torres-Quesada
- Tyrolean Cancer Research Institute (TKFI), Innrain 66, 6020, Innsbruck, Austria.
- Division of Medical Biochemistry, Biocenter, Medical University of Innsbruck, Innrain 80/82, 6020, Innsbruck, Austria.
| |
Collapse
|
6
|
Algül S, Schuldt M, Manders E, Jansen V, Schlossarek S, de Goeij-de Haas R, Henneman AA, Piersma SR, Jimenez CR, Michels M, Carrier L, Helmes M, van der Velden J, Kuster DWD. EGFR/IGF1R Signaling Modulates Relaxation in Hypertrophic Cardiomyopathy. Circ Res 2023; 133:387-399. [PMID: 37477020 DOI: 10.1161/circresaha.122.322133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 07/14/2023] [Indexed: 07/22/2023]
Abstract
BACKGROUND Diastolic dysfunction is central to diseases such as heart failure with preserved ejection fraction and hypertrophic cardiomyopathy (HCM). However, therapies that improve cardiac relaxation are scarce, partly due to a limited understanding of modulators of cardiomyocyte relaxation. We hypothesized that cardiac relaxation is regulated by multiple unidentified proteins and that dysregulation of kinases contributes to impaired relaxation in patients with HCM. METHODS We optimized and increased the throughput of unloaded shortening measurements and screened a kinase inhibitor library in isolated adult cardiomyocytes from wild-type mice. One hundred fifty-seven kinase inhibitors were screened. To assess which kinases are dysregulated in patients with HCM and could contribute to impaired relaxation, we performed a tyrosine and global phosphoproteomics screen and integrative inferred kinase activity analysis using HCM patient myocardium. Identified hits from these 2 data sets were validated in cardiomyocytes from a homozygous MYBPC3c.2373insG HCM mouse model. RESULTS Screening of 157 kinase inhibitors in wild-type (N=33) cardiomyocytes (n=24 563) resulted in the identification of 17 positive inotropes and 21 positive lusitropes, almost all of them novel. The positive lusitropes formed 3 clusters: cell cycle, EGFR (epidermal growth factor receptor)/IGF1R (insulin-like growth factor 1 receptor), and a small Akt (α-serine/threonine protein kinase) signaling cluster. By performing phosphoproteomic profiling of HCM patient myocardium (N=24 HCM and N=8 donors), we demonstrated increased activation of 6 of 8 proteins from the EGFR/IGFR1 cluster in HCM. We validated compounds from this cluster in mouse HCM (N=12) cardiomyocytes (n=2023). Three compounds from this cluster were able to improve relaxation in HCM cardiomyocytes. CONCLUSIONS We showed the feasibility of screening for functional modulators of cardiomyocyte relaxation and contraction, parameters that we observed to be modulated by kinases involved in EGFR/IGF1R, Akt, cell cycle signaling, and FoxO (forkhead box class O) signaling, respectively. Integrating the screening data with phosphoproteomics analysis in HCM patient tissue indicated that inhibition of EGFR/IGF1R signaling is a promising target for treating impaired relaxation in HCM.
Collapse
Affiliation(s)
- Sila Algül
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Cardiovascular Sciences, the Netherlands (S.A., M.S., E.M., V.J., M.H., J.v.d.V., D.W.D.K.)
| | - Maike Schuldt
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Cardiovascular Sciences, the Netherlands (S.A., M.S., E.M., V.J., M.H., J.v.d.V., D.W.D.K.)
| | - Emmy Manders
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Cardiovascular Sciences, the Netherlands (S.A., M.S., E.M., V.J., M.H., J.v.d.V., D.W.D.K.)
- CytoCypher BV, Wageningen, the Netherlands (E.M., M.H.)
| | - Valentijn Jansen
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Cardiovascular Sciences, the Netherlands (S.A., M.S., E.M., V.J., M.H., J.v.d.V., D.W.D.K.)
| | - Saskia Schlossarek
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Germany (S.S., L.C.)
- German Centre for Cardiovascular Research, Partner Site Hamburg/Kiel/Lübeck, Germany (S.S., L.C.)
| | - Richard de Goeij-de Haas
- Department of Medical Oncology, Cancer Center Amsterdam, Amsterdam UMC and Vrije Universiteit Amsterdam, the Netherlands (R.d.G.-d.H., A.A.H., S.R.P., C.R.J.)
| | - Alex A Henneman
- Department of Medical Oncology, Cancer Center Amsterdam, Amsterdam UMC and Vrije Universiteit Amsterdam, the Netherlands (R.d.G.-d.H., A.A.H., S.R.P., C.R.J.)
| | - Sander R Piersma
- Department of Medical Oncology, Cancer Center Amsterdam, Amsterdam UMC and Vrije Universiteit Amsterdam, the Netherlands (R.d.G.-d.H., A.A.H., S.R.P., C.R.J.)
| | - Connie R Jimenez
- Department of Medical Oncology, Cancer Center Amsterdam, Amsterdam UMC and Vrije Universiteit Amsterdam, the Netherlands (R.d.G.-d.H., A.A.H., S.R.P., C.R.J.)
| | - Michelle Michels
- Department of Cardiology, Thoraxcenter, Erasmus Medical Center Rotterdam, the Netherlands (M.M.)
| | - Lucie Carrier
- Institute of Experimental Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Germany (S.S., L.C.)
- German Centre for Cardiovascular Research, Partner Site Hamburg/Kiel/Lübeck, Germany (S.S., L.C.)
| | - Michiel Helmes
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Cardiovascular Sciences, the Netherlands (S.A., M.S., E.M., V.J., M.H., J.v.d.V., D.W.D.K.)
- CytoCypher BV, Wageningen, the Netherlands (E.M., M.H.)
| | - Jolanda van der Velden
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Cardiovascular Sciences, the Netherlands (S.A., M.S., E.M., V.J., M.H., J.v.d.V., D.W.D.K.)
| | - Diederik W D Kuster
- Department of Physiology, Amsterdam UMC, Vrije Universiteit Amsterdam, Amsterdam Cardiovascular Sciences, the Netherlands (S.A., M.S., E.M., V.J., M.H., J.v.d.V., D.W.D.K.)
| |
Collapse
|
7
|
Slika H, Mansour H, Nasser SA, Shaito A, Kobeissy F, Orekhov AN, Pintus G, Eid AH. Epac as a tractable therapeutic target. Eur J Pharmacol 2023; 945:175645. [PMID: 36894048 DOI: 10.1016/j.ejphar.2023.175645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2022] [Revised: 02/26/2023] [Accepted: 03/06/2023] [Indexed: 03/09/2023]
Abstract
In 1957, cyclic adenosine monophosphate (cAMP) was identified as the first secondary messenger, and the first signaling cascade discovered was the cAMP-protein kinase A (PKA) pathway. Since then, cAMP has received increasing attention given its multitude of actions. Not long ago, a new cAMP effector named exchange protein directly activated by cAMP (Epac) emerged as a critical mediator of cAMP's actions. Epac mediates a plethora of pathophysiologic processes and contributes to the pathogenesis of several diseases such as cancer, cardiovascular disease, diabetes, lung fibrosis, neurological disorders, and others. These findings strongly underscore the potential of Epac as a tractable therapeutic target. In this context, Epac modulators seem to possess unique characteristics and advantages and hold the promise of providing more efficacious treatments for a wide array of diseases. This paper provides an in-depth dissection and analysis of Epac structure, distribution, subcellular compartmentalization, and signaling mechanisms. We elaborate on how these characteristics can be utilized to design specific, efficient, and safe Epac agonists and antagonists that can be incorporated into future pharmacotherapeutics. In addition, we provide a detailed portfolio for specific Epac modulators highlighting their discovery, advantages, potential concerns, and utilization in the context of clinical disease entities.
Collapse
Affiliation(s)
- Hasan Slika
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, P.O. Box 11-0236, Lebanon.
| | - Hadi Mansour
- Department of Pharmacology and Toxicology, American University of Beirut, Beirut, P.O. Box 11-0236, Lebanon.
| | | | - Abdullah Shaito
- Biomedical Research Center, Qatar University, Doha, P.O. Box: 2713, Qatar.
| | - Firas Kobeissy
- Department of Neurobiology and Neuroscience, Morehouse School of Medicine, Atlanta, Georgia, USA.
| | - Alexander N Orekhov
- Laboratory of Cellular and Molecular Pathology of Cardiovascular System, Institute of Human Morphology, 3 Tsyurupa Street, Moscow, 117418, Russia; Laboratory of Angiopathology, Institute of General Pathology and Pathophysiology, 8 Baltiiskaya Street, Moscow, 125315, Russia; Institute for Atherosclerosis Research, Skolkovo Innovative Center, Osennyaya Street 4-1-207, Moscow, 121609, Russia.
| | - Gianfranco Pintus
- Department of Biomedical Sciences, University of Sassari, 07100, Sassari, Italy.
| | - Ali H Eid
- Department of Basic Medical Sciences, College of Medicine, QU Health, Qatar University, Doha, P.O. Box 2713, Qatar.
| |
Collapse
|
8
|
Abstract
Protein kinase A (PKA) directly phosphorylates aquaporin-2 (AQP2) water channels in renal collecting ducts to reabsorb water from urine for the maintenance of systemic water homeostasis. More than 50 functionally distinct PKA-anchoring proteins (AKAPs) respectively create compartmentalized PKA signaling to determine the substrate specificity of PKA. Identification of an AKAP responsible for AQP2 phosphorylation is an essential step toward elucidating the molecular mechanisms of urinary concentration. PKA activation by several compounds is a novel screening strategy to uncover PKA substrates whose phosphorylation levels were nearly perfectly correlated with that of AQP2. The leading candidate in this assay proved to be an AKAP termed lipopolysaccharide-responsive and beige-like anchor protein (LRBA). We found that LRBA colocalized with AQP2 in vivo, and Lrba knockout mice displayed a polyuric phenotype with severely impaired AQP2 phosphorylation. Most of the PKA substrates other than AQP2 were adequately phosphorylated by PKA in the absence of LRBA, demonstrating that LRBA-anchored PKA preferentially phosphorylated AQP2 in renal collecting ducts. Furthermore, the LRBA-PKA interaction, rather than other AKAP-PKA interactions, was robustly dissociated by PKA activation. AKAP-PKA interaction inhibitors have attracted attention for their ability to directly phosphorylate AQP2. Therefore, the LRBA-PKA interaction is a promising drug target for the development of anti-aquaretics.
Collapse
|
9
|
A non-catalytic scaffolding activity of hexokinase 2 contributes to EMT and metastasis. Nat Commun 2022; 13:899. [PMID: 35173161 PMCID: PMC8850586 DOI: 10.1038/s41467-022-28440-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 01/20/2022] [Indexed: 02/08/2023] Open
Abstract
Hexokinase 2 (HK2), which catalyzes the first committed step in glucose metabolism, is induced in cancer cells. HK2's role in tumorigenesis has been attributed to its glucose kinase activity. Here, we describe a kinase independent HK2 activity, which contributes to metastasis. HK2 binds and sequesters glycogen synthase kinase 3 (GSK3) and acts as a scaffold forming a ternary complex with the regulatory subunit of protein kinase A (PRKAR1a) and GSK3β to facilitate GSK3β phosphorylation and inhibition by PKA. Thus, HK2 functions as an A-kinase anchoring protein (AKAP). Phosphorylation by GSK3β targets proteins for degradation. Consistently, HK2 increases the level and stability of GSK3 targets, MCL1, NRF2, and particularly SNAIL. In addition to GSK3 inhibition, HK2 kinase activity mediates SNAIL glycosylation, which prohibits its phosphorylation by GSK3. Finally, in mouse models of breast cancer metastasis, HK2 deficiency decreases SNAIL protein levels and inhibits SNAIL-mediated epithelial mesenchymal transition and metastasis.
Collapse
|
10
|
Baltzer S, Bulatov T, Schmied C, Krämer A, Berger BT, Oder A, Walker-Gray R, Kuschke C, Zühlke K, Eichhorst J, Lehmann M, Knapp S, Weston J, von Kries JP, Süssmuth RD, Klussmann E. Aurora Kinase A Is Involved in Controlling the Localization of Aquaporin-2 in Renal Principal Cells. Int J Mol Sci 2022; 23:ijms23020763. [PMID: 35054947 PMCID: PMC8776063 DOI: 10.3390/ijms23020763] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/30/2021] [Accepted: 01/08/2022] [Indexed: 02/01/2023] Open
Abstract
The cAMP-dependent aquaporin-2 (AQP2) redistribution from intracellular vesicles into the plasma membrane of renal collecting duct principal cells induces water reabsorption and fine-tunes body water homeostasis. However, the mechanisms controlling the localization of AQP2 are not understood in detail. Using immortalized mouse medullary collecting duct (MCD4) and primary rat inner medullary collecting duct (IMCD) cells as model systems, we here discovered a key regulatory role of Aurora kinase A (AURKA) in the control of AQP2. The AURKA-selective inhibitor Aurora-A inhibitor I and novel derivatives as well as a structurally different inhibitor, Alisertib, prevented the cAMP-induced redistribution of AQP2. Aurora-A inhibitor I led to a depolymerization of actin stress fibers, which serve as tracks for the translocation of AQP2-bearing vesicles to the plasma membrane. The phosphorylation of cofilin-1 (CFL1) inactivates the actin-depolymerizing function of CFL1. Aurora-A inhibitor I decreased the CFL1 phosphorylation, accounting for the removal of the actin stress fibers and the inhibition of the redistribution of AQP2. Surprisingly, Alisertib caused an increase in actin stress fibers and did not affect CFL1 phosphorylation, indicating that AURKA exerts its control over AQP2 through different mechanisms. An involvement of AURKA and CFL1 in the control of the localization of AQP2 was hitherto unknown.
Collapse
Affiliation(s)
- Sandrine Baltzer
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle-Strasse 10, 13125 Berlin, Germany; (S.B.); (R.W.-G.); (C.K.); (K.Z.)
- Institute of Chemistry, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany; (T.B.); (R.D.S.)
| | - Timur Bulatov
- Institute of Chemistry, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany; (T.B.); (R.D.S.)
| | - Christopher Schmied
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Strasse 10, 13125 Berlin, Germany; (C.S.); (A.O.); (J.E.); (M.L.); (J.P.v.K.)
| | - Andreas Krämer
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Strasse 9, 60438 Frankfurt am Main, Germany; (A.K.); (B.-T.B.); (S.K.)
- Structural Genomics Consortium (SGC), Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue-Strasse 15, 60438 Frankfurt am Main, Germany
- DKTK (German Translational Research Network), Partner Site Frankfurt/Mainz, 60590 Frankfurt am Main, Germany
| | - Benedict-Tilman Berger
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Strasse 9, 60438 Frankfurt am Main, Germany; (A.K.); (B.-T.B.); (S.K.)
- Structural Genomics Consortium (SGC), Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue-Strasse 15, 60438 Frankfurt am Main, Germany
| | - Andreas Oder
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Strasse 10, 13125 Berlin, Germany; (C.S.); (A.O.); (J.E.); (M.L.); (J.P.v.K.)
| | - Ryan Walker-Gray
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle-Strasse 10, 13125 Berlin, Germany; (S.B.); (R.W.-G.); (C.K.); (K.Z.)
| | - Christin Kuschke
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle-Strasse 10, 13125 Berlin, Germany; (S.B.); (R.W.-G.); (C.K.); (K.Z.)
| | - Kerstin Zühlke
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle-Strasse 10, 13125 Berlin, Germany; (S.B.); (R.W.-G.); (C.K.); (K.Z.)
| | - Jenny Eichhorst
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Strasse 10, 13125 Berlin, Germany; (C.S.); (A.O.); (J.E.); (M.L.); (J.P.v.K.)
| | - Martin Lehmann
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Strasse 10, 13125 Berlin, Germany; (C.S.); (A.O.); (J.E.); (M.L.); (J.P.v.K.)
| | - Stefan Knapp
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt, Max-von-Laue-Strasse 9, 60438 Frankfurt am Main, Germany; (A.K.); (B.-T.B.); (S.K.)
- Structural Genomics Consortium (SGC), Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue-Strasse 15, 60438 Frankfurt am Main, Germany
- DKTK (German Translational Research Network), Partner Site Frankfurt/Mainz, 60590 Frankfurt am Main, Germany
- Frankfurt Cancer Institute, 60596 Frankfurt am Main, Germany
| | - John Weston
- JQuest Consulting, Carl-Orff-Weg 25, 65779 Kelkheim, Germany;
| | - Jens Peter von Kries
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Robert-Rössle-Strasse 10, 13125 Berlin, Germany; (C.S.); (A.O.); (J.E.); (M.L.); (J.P.v.K.)
| | - Roderich D. Süssmuth
- Institute of Chemistry, Technische Universität Berlin, Strasse des 17. Juni 135, 10623 Berlin, Germany; (T.B.); (R.D.S.)
| | - Enno Klussmann
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Robert-Rössle-Strasse 10, 13125 Berlin, Germany; (S.B.); (R.W.-G.); (C.K.); (K.Z.)
- DZHK (German Centre for Cardiovascular Research), Partner Site Berlin, 10785 Berlin, Germany
- Correspondence: ; Tel.: +49-30-9406-2596
| |
Collapse
|
11
|
Byrne DP, Omar MH, Kennedy EJ, Eyers PA, Scott JD. Biochemical Analysis of AKAP-Anchored PKA Signaling Complexes. Methods Mol Biol 2022; 2483:297-317. [PMID: 35286684 PMCID: PMC9518671 DOI: 10.1007/978-1-0716-2245-2_19] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Generation of the prototypic second messenger cAMP instigates numerous signaling events. A major intracellular target of cAMP is Protein kinase A (PKA), a Ser/Thr protein kinase. Where and when this enzyme is activated inside the cell has profound implications on the functional impact of PKA. It is now well established that PKA signaling is focused locally into subcellular signaling "islands" or "signalosomes." The A-Kinase Anchoring Proteins (AKAPs) play a critical role in this process by dictating spatial and temporal aspects of PKA action. Genetically encoded biosensors, small molecule and peptide-based disruptors of PKA signaling are valuable tools for rigorous investigation of local PKA action at the biochemical level. This chapter focuses on approaches to evaluate PKA signaling islands, including a simple assay for monitoring the interaction of an AKAP with a tunable PKA holoenzyme. The latter approach evaluates the composition of PKA holoenzymes, in which regulatory subunits and catalytic subunits can be visualized in the presence of test compounds and small-molecule inhibitors.
Collapse
Affiliation(s)
- Dominic P Byrne
- Department of Biochemistry and Systems Biology, ISMIB, University of Liverpool, Liverpool, UK
| | - Mitchell H Omar
- Department of Pharmacology, University of Washington, Seattle, WA, USA
| | - Eileen J Kennedy
- Department of Pharmaceutical and Biomedical Sciences, College of Pharmacy, University of Georgia, Athens, GA, USA
| | - Patrick A Eyers
- Department of Biochemistry and Systems Biology, ISMIB, University of Liverpool, Liverpool, UK.
| | - John D Scott
- Department of Pharmacology, University of Washington, Seattle, WA, USA.
| |
Collapse
|
12
|
Walker-Gray R, Pallien T, Miller DC, Oder A, Neuenschwander M, von Kries JP, Diecke S, Klussmann E. Disruptors of AKAP-Dependent Protein-Protein Interactions. Methods Mol Biol 2022; 2483:117-139. [PMID: 35286673 DOI: 10.1007/978-1-0716-2245-2_8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A-kinase anchoring proteins (AKAPs) are a family of multivalent scaffolding proteins. They engage in direct protein-protein interactions with protein kinases, kinase substrates and further signaling molecules. Each AKAP interacts with a specific set of protein interaction partners and such sets can vary between different cellular compartments and cells. Thus, AKAPs can coordinate signal transduction processes spatially and temporally in defined cellular environments. AKAP-dependent protein-protein interactions are involved in a plethora of physiological processes, including processes in the cardiovascular, nervous, and immune system. Dysregulation of AKAPs and their interactions is associated with or causes widespread diseases, for example, cardiac diseases such as heart failure. However, there are profound shortcomings in understanding functions of specific AKAP-dependent protein-protein interactions. In part, this is due to the lack of agents for specifically targeting defined protein-protein interactions. Peptidic and non-peptidic inhibitors are invaluable molecular tools for elucidating the functions of AKAP-dependent protein-protein interactions. In addition, such interaction disruptors may pave the way to new concepts for the treatment of diseases where AKAP-dependent protein-protein interactions constitute potential drug targets.Here we describe screening approaches for the identification of small molecule disruptors of AKAP-dependent protein-protein interactions. Examples include interactions of AKAP18 and protein kinase A (PKA) and of AKAP-Lbc and RhoA. We discuss a homogenous time-resolved fluorescence (HTRF) and an AlphaScreen® assay for small molecule library screening and human induced pluripotent stem cell-derived cardiac myocytes (hiPSC-CMs) as a cell system for the characterization of identified hits.
Collapse
Affiliation(s)
- Ryan Walker-Gray
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Tamara Pallien
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Duncan C Miller
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), Berlin, Germany
| | - Andreas Oder
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Berlin, Germany
| | | | | | - Sebastian Diecke
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), Berlin, Germany
| | - Enno Klussmann
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.
- DZHK (German Centre for Cardiovascular Research), Berlin, Germany.
| |
Collapse
|
13
|
Olesen ETB, Fenton RA. Aquaporin 2 regulation: implications for water balance and polycystic kidney diseases. Nat Rev Nephrol 2021; 17:765-781. [PMID: 34211154 DOI: 10.1038/s41581-021-00447-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/21/2021] [Indexed: 02/06/2023]
Abstract
Targeting the collecting duct water channel aquaporin 2 (AQP2) to the plasma membrane is essential for the maintenance of mammalian water homeostasis. The vasopressin V2 receptor (V2R), which is a GS protein-coupled receptor that increases intracellular cAMP levels, has a major role in this targeting process. Although a rise in cAMP levels and activation of protein kinase A are involved in facilitating the actions of V2R, studies in knockout mice and cell models have suggested that cAMP signalling pathways are not an absolute requirement for V2R-mediated AQP2 trafficking to the plasma membrane. In addition, although AQP2 phosphorylation is a known prerequisite for V2R-mediated plasma membrane targeting, none of the known AQP2 phosphorylation events appears to be rate-limiting in this process, which suggests the involvement of other factors; cytoskeletal remodelling has also been implicated. Notably, several regulatory processes and signalling pathways involved in AQP2 trafficking also have a role in the pathophysiology of autosomal dominant polycystic kidney disease, although the role of AQP2 in cyst progression is unknown. Here, we highlight advances in the field of AQP2 regulation that might be exploited for the treatment of water balance disorders and provide a rationale for targeting these pathways in autosomal dominant polycystic kidney disease.
Collapse
Affiliation(s)
- Emma T B Olesen
- Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark. .,Department of Endocrinology and Nephrology, North Zealand Hospital, Hillerød, Denmark.
| | - Robert A Fenton
- Department of Biomedicine, Faculty of Health, Aarhus University, Aarhus, Denmark.
| |
Collapse
|
14
|
Ando F. Activation of AQP2 water channels by protein kinase A: therapeutic strategies for congenital nephrogenic diabetes insipidus. Clin Exp Nephrol 2021; 25:1051-1056. [PMID: 34224008 PMCID: PMC8421276 DOI: 10.1007/s10157-021-02108-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 06/27/2021] [Indexed: 01/08/2023]
Abstract
Background Congenital nephrogenic diabetes insipidus (NDI) is primarily caused by loss-of-function mutations in the vasopressin type 2 receptor (V2R). Renal unresponsiveness to the antidiuretic hormone vasopressin impairs aquaporin-2 (AQP2) water channel activity and water reabsorption from urine, resulting in polyuria. Currently available symptomatic treatments inadequately reduce patients’ excessive amounts of urine excretion, threatening their quality of life. In the past 25 years, vasopressin/cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) has been believed to be the most important signaling pathway for AQP2 activation. Although cAMP production without vasopressin is the reasonable therapeutic strategy for congenital NDI caused by V2R mutations, the efficacy of candidate drugs on AQP2 activation is far less than that of vasopressin. Results Intracellular distribution and activity of PKA are largely controlled by its scaffold proteins, A-kinase anchoring proteins (AKAPs). Dissociating the binding of AKAPs and PKA significantly increased PKA activity in the renal collecting ducts and activated AQP2 phosphorylation and trafficking. Remarkably, the AKAPs–PKA disruptor FMP-API-1 increased transcellular water permeability in isolated renal collecting ducts to the same extent as vasopressin. Moreover, derivatives of FMP-API-1 possessed much more high potency. FMP-API-1/27 is the first low-molecular-weight compound to be discovered that can phosphorylate AQP2 more effectively than preexisting drug candidates. Conclusion AKAP-PKA disruptors are a promising therapeutic target for congenital NDI. In this article, we shall discuss the pathophysiological roles of PKA and novel strategies to activate PKA in renal collecting ducts.
Collapse
Affiliation(s)
- Fumiaki Ando
- Department of Nephrology, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8510, Japan.
| |
Collapse
|
15
|
The electrophysiological effects of cannabidiol on action potentials and transmembrane potassium currents in rabbit and dog cardiac ventricular preparations. Arch Toxicol 2021; 95:2497-2505. [PMID: 34031697 PMCID: PMC8241752 DOI: 10.1007/s00204-021-03086-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Accepted: 05/17/2021] [Indexed: 12/24/2022]
Abstract
Cannabis use is associated with known cardiovascular side effects such as cardiac arrhythmias or even sudden cardiac death. The mechanisms behind these adverse effects are unknown. The aim of the present work was to study the cellular cardiac electrophysiological effects of cannabidiol (CBD) on action potentials and several transmembrane potassium currents, such as the rapid (IKr) and slow (IKs) delayed rectifier, the transient outward (Ito) and inward rectifier (IK1) potassium currents in rabbit and dog cardiac preparations. CBD increased action potential duration (APD) significantly in both rabbit (from 211.7 ± 11.2. to 224.6 ± 11.4 ms, n = 8) and dog (from 215.2 ± 9.0 to 231.7 ± 4.7 ms, n = 6) ventricular papillary muscle at 5 µM concentration. CBD decreased IKr, IKs and Ito (only in dog) significantly with corresponding estimated EC50 values of 4.9, 3.1 and 5 µM, respectively, without changing IK1. Although the EC50 value of CBD was found to be higher than literary Cmax values after CBD smoking and oral intake, our results raise the possibility that potassium channel inhibition by lengthening cardiac repolarization might have a role in the possible proarrhythmic side effects of cannabinoids in situations where CBD metabolism and/or the repolarization reserve is impaired.
Collapse
|
16
|
Sholokh A, Klussmann E. Local cyclic adenosine monophosphate signalling cascades-Roles and targets in chronic kidney disease. Acta Physiol (Oxf) 2021; 232:e13641. [PMID: 33660401 DOI: 10.1111/apha.13641] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 02/26/2021] [Accepted: 03/01/2021] [Indexed: 12/20/2022]
Abstract
The molecular mechanisms underlying chronic kidney disease (CKD) are poorly understood and treatment options are limited, a situation underpinning the need for elucidating the causative molecular mechanisms and for identifying innovative treatment options. It is emerging that cyclic 3',5'-adenosine monophosphate (cAMP) signalling occurs in defined cellular compartments within nanometre dimensions in processes whose dysregulation is associated with CKD. cAMP compartmentalization is tightly controlled by a specific set of proteins, including A-kinase anchoring proteins (AKAPs) and phosphodiesterases (PDEs). AKAPs such as AKAP18, AKAP220, AKAP-Lbc and STUB1, and PDE4 coordinate arginine-vasopressin (AVP)-induced water reabsorption by collecting duct principal cells. However, hyperactivation of the AVP system is associated with kidney damage and CKD. Podocyte injury involves aberrant AKAP signalling. cAMP signalling in immune cells can be local and slow the progression of inflammatory processes typical for CKD. A major risk factor of CKD is hypertension. cAMP directs the release of the blood pressure regulator, renin, from juxtaglomerular cells, and plays a role in Na+ reabsorption through ENaC, NKCC2 and NCC in the kidney. Mutations in the cAMP hydrolysing PDE3A that cause lowering of cAMP lead to hypertension. Another major risk factor of CKD is diabetes mellitus. AKAP18 and AKAP150 and several PDEs are involved in insulin release. Despite the increasing amount of data, an understanding of functions of compartmentalized cAMP signalling with relevance for CKD is fragmentary. Uncovering functions will improve the understanding of physiological processes and identification of disease-relevant aberrations may guide towards new therapeutic concepts for the treatment of CKD.
Collapse
Affiliation(s)
- Anastasiia Sholokh
- Max‐Delbrück‐Center for Molecular Medicine (MDC) Helmholtz Association Berlin Germany
| | - Enno Klussmann
- Max‐Delbrück‐Center for Molecular Medicine (MDC) Helmholtz Association Berlin Germany
- DZHK (German Centre for Cardiovascular Research) Berlin Germany
| |
Collapse
|
17
|
Abstract
The field of cAMP signaling is witnessing exciting developments with the recognition that cAMP is compartmentalized and that spatial regulation of cAMP is critical for faithful signal coding. This realization has changed our understanding of cAMP signaling from a model in which cAMP connects a receptor at the plasma membrane to an intracellular effector in a linear pathway to a model in which cAMP signals propagate within a complex network of alternative branches and the specific functional outcome strictly depends on local regulation of cAMP levels and on selective activation of a limited number of branches within the network. In this review, we cover some of the early studies and summarize more recent evidence supporting the model of compartmentalized cAMP signaling, and we discuss how this knowledge is starting to provide original mechanistic insight into cell physiology and a novel framework for the identification of disease mechanisms that potentially opens new avenues for therapeutic interventions.
Collapse
Affiliation(s)
- Manuela Zaccolo
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Anna Zerio
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Miguel J Lobo
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
18
|
Bernier LP, Bohlen CJ, York EM, Choi HB, Kamyabi A, Dissing-Olesen L, Hefendehl JK, Collins HY, Stevens B, Barres BA, MacVicar BA. Nanoscale Surveillance of the Brain by Microglia via cAMP-Regulated Filopodia. Cell Rep 2020; 27:2895-2908.e4. [PMID: 31167136 DOI: 10.1016/j.celrep.2019.05.010] [Citation(s) in RCA: 119] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/14/2019] [Accepted: 04/30/2019] [Indexed: 02/07/2023] Open
Abstract
Microglia, the brain's immune cells, maintain homeostasis and sense pathological changes by continuously surveying the parenchyma with highly motile large processes. Here, we demonstrate that microglia also use thin actin-dependent filopodia that allow fast nanoscale sensing within discrete regions. Filopodia are distinct from large processes by their size, speed, and regulation mechanism. Increasing cyclic AMP (cAMP) by activating norepinephrine Gs-coupled receptors, applying nitric oxide, or inhibiting phosphodiesterases rapidly increases filopodia but collapses large processes. Alternatively, Gi-coupled P2Y12 receptor activation collapses filopodia but triggers large processes extension with bulbous tips. Similar control of cytoskeletal dynamics and microglial morphology by cAMP is observed in ramified primary microglia, suggesting that filopodia are intrinsically generated sensing structures. Therefore, nanoscale surveillance of brain parenchyma by microglia requires localized cAMP increases that drive filopodia formation. Shifting intracellular cAMP levels controls the polarity of microglial responses to changes in brain homeostasis and alters the scale of immunosurveillance.
Collapse
Affiliation(s)
- Louis-Philippe Bernier
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada.
| | - Christopher J Bohlen
- Stanford University School of Medicine, Department of Neurobiology, Stanford, CA 94305, USA
| | - Elisa M York
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada
| | - Hyun B Choi
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada
| | - Alireza Kamyabi
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada
| | - Lasse Dissing-Olesen
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada; F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School Boston, MA 02115, USA
| | - Jasmin K Hefendehl
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada
| | - Hannah Y Collins
- Stanford University School of Medicine, Department of Neurobiology, Stanford, CA 94305, USA
| | - Beth Stevens
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School Boston, MA 02115, USA
| | - Ben A Barres
- Stanford University School of Medicine, Department of Neurobiology, Stanford, CA 94305, USA
| | - Brian A MacVicar
- University of British Columbia, Djavad Mowafaghian Centre for Brain Health, Vancouver, BC V6T 1Z3, Canada.
| |
Collapse
|
19
|
Bucko PJ, Scott JD. Drugs That Regulate Local Cell Signaling: AKAP Targeting as a Therapeutic Option. Annu Rev Pharmacol Toxicol 2020; 61:361-379. [PMID: 32628872 DOI: 10.1146/annurev-pharmtox-022420-112134] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cells respond to environmental cues by mobilizing signal transduction cascades that engage protein kinases and phosphoprotein phosphatases. Correct organization of these enzymes in space and time enables the efficient and precise transmission of chemical signals. The cyclic AMP-dependent protein kinase A is compartmentalized through its association with A-kinase anchoring proteins (AKAPs). AKAPs are a family of multivalent scaffolds that constrain signaling enzymes and effectors at subcellular locations to drive essential physiological events. More recently, it has been recognized that defective signaling in certain endocrine disorders and cancers proceeds through pathological AKAP complexes. Consequently, pharmacologically targeting these macromolecular complexes unlocks new therapeutic opportunities for a growing number of clinical indications. This review highlights recent findings on AKAP signaling in disease, particularly in certain cancers, and offers an overview of peptides and small molecules that locally regulate AKAP-binding partners.
Collapse
Affiliation(s)
- Paula J Bucko
- Department of Pharmacology, University of Washington, Seattle, Washington 98195, USA; ,
| | - John D Scott
- Department of Pharmacology, University of Washington, Seattle, Washington 98195, USA; ,
| |
Collapse
|
20
|
Fu Z, Gong L, Liu J, Wu J, Barrett EJ, Aylor KW, Liu Z. Brain Endothelial Cells Regulate Glucagon-Like Peptide 1 Entry Into the Brain via a Receptor-Mediated Process. Front Physiol 2020; 11:555. [PMID: 32547420 PMCID: PMC7274078 DOI: 10.3389/fphys.2020.00555] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 05/04/2020] [Indexed: 01/01/2023] Open
Abstract
Glucagon-like peptide 1 (GLP-1) in addition to regulating glucose-dependent insulin and glucagon secretion exerts anorexic and neuroprotective effects. While brain-derived GLP-1 may participate in these central actions, evidence suggests that peripherally derived GLP-1 plays an important role and GLP-1 analogs are known to cross the blood brain barrier. To define the role of brain microvascular endothelial cells in GLP-1 entry into the brain, we infused labeled GLP-1 or exendin-4 into rats intravenously and examined their appearance and protein kinase A activities in various brain regions. We also studied the role of endothelial cell GLP-1 receptor and its signaling in endothelial cell uptake and transport of GLP-1. Systemically infused labeled GLP-1 or exendin-4 appeared rapidly in various brain regions and this was associated with increased protein kinase A activity in these brain regions. Pretreatment with GLP-1 receptor antagonist reduced labeled GLP-1 or exendin-4 enrichment in the brain. Sub-diaphragmatic vagus nerve resection did not alter GLP-1-mediated increases in protein kinase A activity in the brain. Rat brain microvascular endothelial cells rapidly took up labeled GLP-1 and this was blunted by either GLP-1 receptor antagonism or protein kinase A inhibition but enhanced through adenylyl cyclase activation. Using an artificially assembled blood brain barrier consisting of endothelial and astrocyte layers, we found that labeled GLP-1 time-dependently crossed the barrier and the presence of GLP-1 receptor antagonist blunted this transit. We conclude that GLP-1 crosses the blood brain barrier through active trans-endothelial transport which requires GLP-1 receptor binding and activation.
Collapse
Affiliation(s)
- Zhuo Fu
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Liying Gong
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States.,Department of Pharmacology, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Jia Liu
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Jing Wu
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States.,Department of Endocrinology, Xiangya Hospital, Central South University, Changsha, China
| | - Eugene J Barrett
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Kevin W Aylor
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| | - Zhenqi Liu
- Division of Endocrinology and Metabolism, Department of Medicine, University of Virginia Health System, Charlottesville, VA, United States
| |
Collapse
|
21
|
Sussman CR, Wang X, Chebib FT, Torres VE. Modulation of polycystic kidney disease by G-protein coupled receptors and cyclic AMP signaling. Cell Signal 2020; 72:109649. [PMID: 32335259 DOI: 10.1016/j.cellsig.2020.109649] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 04/16/2020] [Accepted: 04/17/2020] [Indexed: 12/11/2022]
Abstract
Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a systemic disorder associated with polycystic liver disease (PLD) and other extrarenal manifestations, the most common monogenic cause of end-stage kidney disease, and a major burden for public health. Many studies have shown that alterations in G-protein and cAMP signaling play a central role in its pathogenesis. As for many other diseases (35% of all approved drugs target G-protein coupled receptors (GPCRs) or proteins functioning upstream or downstream from GPCRs), treatments targeting GPCR have shown effectiveness in slowing the rate of progression of ADPKD. Tolvaptan, a vasopressin V2 receptor antagonist is the first drug approved by regulatory agencies to treat rapidly progressive ADPKD. Long-acting somatostatin analogs have also been effective in slowing the rates of growth of polycystic kidneys and liver. Although no treatment has so far been able to prevent the development or stop the progression of the disease, these encouraging advances point to G-protein and cAMP signaling as a promising avenue of investigation that may lead to more effective and safe treatments. This will require a better understanding of the relevant GPCRs, G-proteins, cAMP effectors, and of the enzymes and A-kinase anchoring proteins controlling the compartmentalization of cAMP signaling. The purpose of this review is to provide an overview of general GPCR signaling; the function of polycystin-1 (PC1) as a putative atypical adhesion GPCR (aGPCR); the roles of PC1, polycystin-2 (PC2) and the PC1-PC2 complex in the regulation of calcium and cAMP signaling; the cross-talk of calcium and cAMP signaling in PKD; and GPCRs, adenylyl cyclases, cyclic nucleotide phosphodiesterases, and protein kinase A as therapeutic targets in ADPKD.
Collapse
Affiliation(s)
- Caroline R Sussman
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America
| | - Xiaofang Wang
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America
| | - Fouad T Chebib
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America
| | - Vicente E Torres
- Division of Nephrology and Hypertension, Mayo Clinic, Rochester, MN, United States of America.
| |
Collapse
|
22
|
New aspects in cardiac L-type Ca2+ channel regulation. Biochem Soc Trans 2020; 48:39-49. [PMID: 32065210 DOI: 10.1042/bst20190229] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/24/2020] [Accepted: 01/24/2020] [Indexed: 12/23/2022]
Abstract
Cardiac excitation-contraction coupling is initiated with the influx of Ca2+ ions across the plasma membrane through voltage-gated L-type calcium channels. This process is tightly regulated by modulation of the channel open probability and channel localization. Protein kinase A (PKA) is found in close association with the channel and is one of the main regulators of its function. Whether this kinase is modulating the channel open probability by phosphorylation of key residues or via alternative mechanisms is unclear. This review summarizes recent findings regarding the PKA-mediated channel modulation and will highlight recently discovered regulatory mechanisms that are independent of PKA activity and involve protein-protein interactions and channel localization.
Collapse
|
23
|
Marin W. A-kinase anchoring protein 1 (AKAP1) and its role in some cardiovascular diseases. J Mol Cell Cardiol 2019; 138:99-109. [PMID: 31783032 DOI: 10.1016/j.yjmcc.2019.11.154] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 11/08/2019] [Accepted: 11/22/2019] [Indexed: 01/09/2023]
Abstract
A-kinase anchoring proteins (AKAPs) play crucial roles in regulating compartmentalized multi-protein signaling networks related to PKA-mediated phosphorylation. The mitochondrial AKAP - AKAP1 proteins are enriched in heart and play cardiac protective roles. This review aims to thoroughly summarize AKAP1 variants from their sequence features to the structure-function relationships between AKAP1 and its binding partners, as well as the molecular mechanisms of AKAP1 in cardiac hypertrophy, hypoxia-induced myocardial infarction and endothelial cells dysfunction, suggesting AKAP1 as a candidate for cardiovascular therapy.
Collapse
Affiliation(s)
- Wenwen Marin
- Institute for Translational Medicine, Medical Faculty of Qingdao University, Qingdao 266021, China.
| |
Collapse
|
24
|
Zhao X, Nedvetsky P, Stanchi F, Vion AC, Popp O, Zühlke K, Dittmar G, Klussmann E, Gerhardt H. Endothelial PKA activity regulates angiogenesis by limiting autophagy through phosphorylation of ATG16L1. eLife 2019; 8:e46380. [PMID: 31580256 PMCID: PMC6797479 DOI: 10.7554/elife.46380] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 10/01/2019] [Indexed: 12/15/2022] Open
Abstract
The cAMP-dependent protein kinase A (PKA) regulates various cellular functions in health and disease. In endothelial cells PKA activity promotes vessel maturation and limits tip cell formation. Here, we used a chemical genetic screen to identify endothelial-specific direct substrates of PKA in human umbilical vein endothelial cells (HUVEC) that may mediate these effects. Amongst several candidates, we identified ATG16L1, a regulator of autophagy, as novel target of PKA. Biochemical validation, mass spectrometry and peptide spot arrays revealed that PKA phosphorylates ATG16L1α at Ser268 and ATG16L1β at Ser269, driving phosphorylation-dependent degradation of ATG16L1 protein. Reducing PKA activity increased ATG16L1 protein levels and endothelial autophagy. Mouse in vivo genetics and pharmacological experiments demonstrated that autophagy inhibition partially rescues vascular hypersprouting caused by PKA deficiency. Together these results indicate that endothelial PKA activity mediates a critical switch from active sprouting to quiescence in part through phosphorylation of ATG16L1, which in turn reduces endothelial autophagy.
Collapse
Affiliation(s)
- Xiaocheng Zhao
- Vascular Patterning Laboratory, Center for Cancer BiologyVIBLeuvenBelgium
- Vascular Patterning Laboratory, Center for Cancer Biology, Department of OncologyVIBLeuvenBelgium
| | - Pavel Nedvetsky
- Vascular Patterning Laboratory, Center for Cancer BiologyVIBLeuvenBelgium
- Vascular Patterning Laboratory, Center for Cancer Biology, Department of OncologyVIBLeuvenBelgium
- Medical Cell Biology, Medical Clinic DUniversity Hospital MünsterMünsterGermany
| | - Fabio Stanchi
- Vascular Patterning Laboratory, Center for Cancer BiologyVIBLeuvenBelgium
- Vascular Patterning Laboratory, Center for Cancer Biology, Department of OncologyVIBLeuvenBelgium
| | - Anne-Clemence Vion
- Integrative Vascular Biology LabMax-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC)BerlinGermany
- INSERM UMR-970, Paris Cardiovascular Research CenterParis Descartes UniversityParisFrance
| | - Oliver Popp
- ProteomicsMax-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC)BerlinGermany
| | - Kerstin Zühlke
- Anchored Signaling LabMax-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC)BerlinGermany
| | - Gunnar Dittmar
- ProteomicsMax-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC)BerlinGermany
- CRP Santé · Department of OncologyLIH Luxembourg Institute of HealthLuxembourgLuxembourg
| | - Enno Klussmann
- Anchored Signaling LabMax-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC)BerlinGermany
- DZHK (German Center for Cardiovascular Research)BerlinGermany
| | - Holger Gerhardt
- Vascular Patterning Laboratory, Center for Cancer BiologyVIBLeuvenBelgium
- Vascular Patterning Laboratory, Center for Cancer Biology, Department of OncologyVIBLeuvenBelgium
- Integrative Vascular Biology LabMax-Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC)BerlinGermany
- DZHK (German Center for Cardiovascular Research)BerlinGermany
- Berlin Institute of Health (BIH)BerlinGermany
| |
Collapse
|
25
|
Mabonga L, Kappo AP. Protein-protein interaction modulators: advances, successes and remaining challenges. Biophys Rev 2019; 11:559-581. [PMID: 31301019 DOI: 10.1007/s12551-019-00570-x] [Citation(s) in RCA: 114] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 06/24/2019] [Indexed: 12/12/2022] Open
Abstract
Modulating disease-relevant protein-protein interactions (PPIs) using small-molecule inhibitors is a quite indispensable diagnostic and therapeutic strategy in averting pathophysiological cues and disease progression. Over the years, targeting intracellular PPIs as drug design targets has been a challenging task owing to their highly dynamic and expansive interfacial areas (flat, featureless and relatively large). However, advances in PPI-focused drug discovery technology have been reported and a few drugs are already on the market, with some potential drug-like candidates already in clinical trials. In this article, we review the advances, successes and remaining challenges in the application of small molecules as valuable PPI modulators in disease diagnosis and therapeutics.
Collapse
Affiliation(s)
- Lloyd Mabonga
- Biotechnology and Structural Biology (BSB) Group, Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa, 3886, South Africa
| | - Abidemi Paul Kappo
- Biotechnology and Structural Biology (BSB) Group, Department of Biochemistry and Microbiology, University of Zululand, KwaDlangezwa, 3886, South Africa.
| |
Collapse
|
26
|
Baltzer S, Klussmann E. Small molecules for modulating the localisation of the water channel aquaporin-2-disease relevance and perspectives for targeting local cAMP signalling. Naunyn Schmiedebergs Arch Pharmacol 2019; 392:1049-1064. [PMID: 31300862 DOI: 10.1007/s00210-019-01686-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 06/26/2019] [Indexed: 12/23/2022]
Abstract
The tight spatial and temporal organisation of cyclic adenosine monophosphate (cAMP) signalling plays a key role in arginine-vasopressin (AVP)-mediated water reabsorption in renal collecting duct principal cells and in a plethora of other processes such as in the control of cardiac myocyte contractility. This review critically discusses in vitro- and cell-based screening strategies for the identification of small molecules that interfere with AVP/cAMP signalling in renal principal cells; it features phenotypic screening and approaches for targeting protein-protein interactions of A-kinase anchoring proteins (AKAPs), which organise local cAMP signalling hubs. The discovery of novel chemical entities for the modulation of local cAMP will not only provide tools for elucidating molecular mechanisms underlying cAMP signalling. Novel chemical entities can also serve as starting points for the development of novel drugs for the treatment of human diseases. Examples illustrate how screening for small molecules can pave the way to novel approaches for the treatment of certain forms of diabetes insipidus, a disease caused by defects in AVP-mediated water reabsorption.
Collapse
Affiliation(s)
- Sandrine Baltzer
- Max Delbrück Center for Molecular Medicine Berlin (MDC), Helmholtz Association, Robert-Rössle-Strasse 10, 13125, Berlin, Germany
| | - Enno Klussmann
- Max Delbrück Center for Molecular Medicine Berlin (MDC), Helmholtz Association, Robert-Rössle-Strasse 10, 13125, Berlin, Germany. .,DZHK (German Centre for Cardiovascular Research), partner site Berlin, Berlin, Germany. .,Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health and Vegetative Physiology, Berlin, Germany.
| |
Collapse
|
27
|
Vukićević T, Hinze C, Baltzer S, Himmerkus N, Quintanova C, Zühlke K, Compton F, Ahlborn R, Dema A, Eichhorst J, Wiesner B, Bleich M, Schmidt-Ott KM, Klussmann E. Fluconazole Increases Osmotic Water Transport in Renal Collecting Duct through Effects on Aquaporin-2 Trafficking. J Am Soc Nephrol 2019; 30:795-810. [PMID: 30988011 DOI: 10.1681/asn.2018060668] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 02/13/2019] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Arginine-vasopressin (AVP) binding to vasopressin V2 receptors promotes redistribution of the water channel aquaporin-2 (AQP2) from intracellular vesicles into the plasma membrane of renal collecting duct principal cells. This pathway fine-tunes renal water reabsorption and urinary concentration, and its perturbation is associated with diabetes insipidus. Previously, we identified the antimycotic drug fluconazole as a potential modulator of AQP2 localization. METHODS We assessed the influence of fluconazole on AQP2 localization in vitro and in vivo as well as the drug's effects on AQP2 phosphorylation and RhoA (a small GTPase, which under resting conditions, maintains F-actin to block AQP2-bearing vesicles from reaching the plasma membrane). We also tested fluconazole's effects on water flow across epithelia of isolated mouse collecting ducts and on urine output in mice treated with tolvaptan, a VR2 blocker that causes a nephrogenic diabetes insipidus-like excessive loss of hypotonic urine. RESULTS Fluconazole increased plasma membrane localization of AQP2 in principal cells independent of AVP. It also led to an increased AQP2 abundance associated with alterations in phosphorylation status and ubiquitination as well as inhibition of RhoA. In isolated mouse collecting ducts, fluconazole increased transepithelial water reabsorption. In mice, fluconazole increased collecting duct AQP2 plasma membrane localization and reduced urinary output. Fluconazole also reduced urinary output in tolvaptan-treated mice. CONCLUSIONS Fluconazole promotes collecting duct AQP2 plasma membrane localization in the absence of AVP. Therefore, it might have utility in treating forms of diabetes insipidus (e.g., X-linked nephrogenic diabetes insipidus) in which the kidney responds inappropriately to AVP.
Collapse
Affiliation(s)
- Tanja Vukićević
- Max Delbrück Center for Molecular Medicine Berlin, (MDC), Research area Cardiovascular & Metabolic Disease, Berlin, Germany
| | - Christian Hinze
- Max Delbrück Center for Molecular Medicine Berlin, (MDC), Research area Cardiovascular & Metabolic Disease, Berlin, Germany.,Department of Nephrology and Medical Intensive Care and.,Berlin Institute of Health, Berlin, Germany
| | - Sandrine Baltzer
- Max Delbrück Center for Molecular Medicine Berlin, (MDC), Research area Cardiovascular & Metabolic Disease, Berlin, Germany
| | - Nina Himmerkus
- Institute of Physiology, Christian Albrechts University Kiel, Kiel, Germany
| | | | - Kerstin Zühlke
- Max Delbrück Center for Molecular Medicine Berlin, (MDC), Research area Cardiovascular & Metabolic Disease, Berlin, Germany
| | - Friederike Compton
- Department of Nephrology and Medical Intensive Care and.,Berlin Institute of Health, Berlin, Germany
| | - Robert Ahlborn
- Information Technology Department, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Alessandro Dema
- Max Delbrück Center for Molecular Medicine Berlin, (MDC), Research area Cardiovascular & Metabolic Disease, Berlin, Germany
| | - Jenny Eichhorst
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Cellular Imaging, Berlin, Germany
| | - Burkhard Wiesner
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Cellular Imaging, Berlin, Germany
| | - Markus Bleich
- Institute of Physiology, Christian Albrechts University Kiel, Kiel, Germany
| | - Kai M Schmidt-Ott
- Max Delbrück Center for Molecular Medicine Berlin, (MDC), Research area Cardiovascular & Metabolic Disease, Berlin, Germany; .,Department of Nephrology and Medical Intensive Care and.,Berlin Institute of Health, Berlin, Germany
| | - Enno Klussmann
- Max Delbrück Center for Molecular Medicine Berlin, (MDC), Research area Cardiovascular & Metabolic Disease, Berlin, Germany; .,German Centre for Cardiovascular Research (DZHK), Partner Site Berlin, Berlin, Germany; and.,Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Vegetative Physiology, Berlin, Germany
| |
Collapse
|
28
|
Van Laar VS, Otero PA, Hastings TG, Berman SB. Potential Role of Mic60/Mitofilin in Parkinson's Disease. Front Neurosci 2019; 12:898. [PMID: 30740041 PMCID: PMC6357844 DOI: 10.3389/fnins.2018.00898] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 11/16/2018] [Indexed: 12/21/2022] Open
Abstract
There are currently no treatments that hinder or halt the inexorable progression of Parkinson's disease (PD). While the etiology of PD remains elusive, evidence suggests that early dysfunction of mitochondrial respiration and homeostasis play a major role in PD pathogenesis. The mitochondrial structural protein Mic60, also known as mitofilin, is critical for maintaining mitochondrial architecture and function. Loss of Mic60 is associated with detrimental effects on mitochondrial homeostasis. Growing evidence now implicates Mic60 in the pathogenesis of PD. In this review, we discuss the data supporting a role of Mic60 and mitochondrial dysfunction in PD. We will also consider the potential of Mic60 as a therapeutic target for treating neurological disorders.
Collapse
Affiliation(s)
- Victor S Van Laar
- Department of Neurology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, United States
| | - P Anthony Otero
- Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, United States.,Division of Neuropathology, Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Cellular and Molecular Pathology (CMP) Program, Department of Pathology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Teresa G Hastings
- Department of Neurology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, United States.,Department of Neuroscience, University of Pittsburgh, Pittsburgh, PA, United States
| | - Sarah B Berman
- Department of Neurology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States.,Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh, Pittsburgh, PA, United States.,Clinical and Translational Science Institute, University of Pittsburgh, Pittsburgh, PA, United States
| |
Collapse
|
29
|
Zhang Y, Huang Y, Srivathsan A, Lim TK, Lin Q, He CY. The unusual flagellar-targeting mechanism and functions of the trypanosome ortholog of the ciliary GTPase Arl13b. J Cell Sci 2018; 131:jcs.219071. [PMID: 30097558 PMCID: PMC6140319 DOI: 10.1242/jcs.219071] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2018] [Accepted: 07/28/2018] [Indexed: 12/11/2022] Open
Abstract
The small GTPase Arl13b is one of the most conserved and ancient ciliary proteins. In human and animals, Arl13b is primarily associated with the ciliary membrane, where it acts as a guanine-nucleotide-exchange factor (GEF) for Arl3 and is implicated in a variety of ciliary and cellular functions. We have identified and characterized Trypanosoma brucei (Tb)Arl13, the sole Arl13b homolog in this evolutionarily divergent, protozoan parasite. TbArl13 has conserved flagellar functions and exhibits catalytic activity towards two different TbArl3 homologs. However, TbArl13 is distinctly associated with the axoneme through a dimerization/docking (D/D) domain. Replacing the D/D domain with a sequence encoding a flagellar membrane protein created a viable alternative to the wild-type TbArl13 in our RNA interference (RNAi)-based rescue assay. Therefore, flagellar enrichment is crucial for TbArl13, but mechanisms to achieve this could be flexible. Our findings thus extend the understanding of the roles of Arl13b and Arl13b–Arl3 pathway in a divergent flagellate of medical importance. This article has an associated First Person interview with the first author of the paper. Highlighted Article: All roads lead to cilia – how the essential flagellar enrichment of Arl13 is achieved in trypanosome cells using a fundamentally different strategy compared with that of animal cells.
Collapse
Affiliation(s)
- Yiliu Zhang
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543
| | - Yameng Huang
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543
| | - Amrita Srivathsan
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543
| | - Teck Kwang Lim
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543
| | - Qingsong Lin
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543
| | - Cynthia Y He
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, Singapore 117543
| |
Collapse
|
30
|
Paruchuri S, Thodeti CK. Form follows function: polymorphisms in mAKAP alter cardiac cAMP/PKA signaling. Am J Physiol Heart Circ Physiol 2018; 315:H626-H628. [PMID: 29727216 DOI: 10.1152/ajpheart.00248.2018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
| | - Charles K Thodeti
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, Ohio
| |
Collapse
|
31
|
AKAPs-PKA disruptors increase AQP2 activity independently of vasopressin in a model of nephrogenic diabetes insipidus. Nat Commun 2018; 9:1411. [PMID: 29650969 PMCID: PMC5897355 DOI: 10.1038/s41467-018-03771-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 03/09/2018] [Indexed: 02/08/2023] Open
Abstract
Congenital nephrogenic diabetes insipidus (NDI) is characterized by the inability of the kidney to concentrate urine. Congenital NDI is mainly caused by loss-of-function mutations in the vasopressin type 2 receptor (V2R), leading to impaired aquaporin-2 (AQP2) water channel activity. So far, treatment options of congenital NDI either by rescuing mutant V2R with chemical chaperones or by elevating cyclic adenosine monophosphate (cAMP) levels have failed to yield effective therapies. Here we show that inhibition of A-kinase anchoring proteins (AKAPs) binding to PKA increases PKA activity and activates AQP2 channels in cortical collecting duct cells. In vivo, the low molecular weight compound 3,3′-diamino-4,4′-dihydroxydiphenylmethane (FMP-API-1) and its derivatives increase AQP2 activity to the same extent as vasopressin, and increase urine osmolality in the context of V2R inhibition. We therefore suggest that FMP-API-1 may constitute a promising lead compound for the treatment of congenital NDI caused by V2R mutations. Patients suffering from congenital nephrogenic diabetes insipidus (NDI) fail to concentrate urine due to mutations in vasopressin type 2 receptor (V2R). Here Ando et al. show that agents disrupting the interaction between PKA and AKAPs restore aquaporin-2 activity downstream of V2R, offering a therapeutic approach for the treatment of NDI.
Collapse
|
32
|
Ercu M, Klussmann E. Roles of A-Kinase Anchoring Proteins and Phosphodiesterases in the Cardiovascular System. J Cardiovasc Dev Dis 2018; 5:jcdd5010014. [PMID: 29461511 PMCID: PMC5872362 DOI: 10.3390/jcdd5010014] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 02/16/2018] [Accepted: 02/18/2018] [Indexed: 12/13/2022] Open
Abstract
A-kinase anchoring proteins (AKAPs) and cyclic nucleotide phosphodiesterases (PDEs) are essential enzymes in the cyclic adenosine 3′-5′ monophosphate (cAMP) signaling cascade. They establish local cAMP pools by controlling the intensity, duration and compartmentalization of cyclic nucleotide-dependent signaling. Various members of the AKAP and PDE families are expressed in the cardiovascular system and direct important processes maintaining homeostatic functioning of the heart and vasculature, e.g., the endothelial barrier function and excitation-contraction coupling. Dysregulation of AKAP and PDE function is associated with pathophysiological conditions in the cardiovascular system including heart failure, hypertension and atherosclerosis. A number of diseases, including autosomal dominant hypertension with brachydactyly (HTNB) and type I long-QT syndrome (LQT1), result from mutations in genes encoding for distinct members of the two classes of enzymes. This review provides an overview over the AKAPs and PDEs relevant for cAMP compartmentalization in the heart and vasculature and discusses their pathophysiological role as well as highlights the potential benefits of targeting these proteins and their protein-protein interactions for the treatment of cardiovascular diseases.
Collapse
Affiliation(s)
- Maria Ercu
- Max Delbrück Center for Molecular Medicine Berlin (MDC), Berlin 13125, Germany.
| | - Enno Klussmann
- Max Delbrück Center for Molecular Medicine Berlin (MDC), Berlin 13125, Germany.
- DZHK (German Centre for Cardiovascular Research), partner site Berlin 13347, Germany.
| |
Collapse
|
33
|
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: 40] [Impact Index Per Article: 5.7] [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.
Collapse
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.
| |
Collapse
|
34
|
Cserne Szappanos H, Muralidharan P, Ingley E, Petereit J, Millar AH, Hool LC. Identification of a novel cAMP dependent protein kinase A phosphorylation site on the human cardiac calcium channel. Sci Rep 2017; 7:15118. [PMID: 29123182 PMCID: PMC5680263 DOI: 10.1038/s41598-017-15087-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 10/19/2017] [Indexed: 11/09/2022] Open
Abstract
The "Fight or Flight" response is elicited by extrinsic stress and is necessary in many species for survival. The response involves activation of the β-adrenergic signalling pathway. Surprisingly the mechanisms have remained unresolved. Calcium influx through the cardiac L-type Ca2+ channel (Cav1.2) is absolutely required. Here we identify the functionally relevant site for PKA phosphorylation on the human cardiac L-type Ca2+ channel pore forming α1 subunit using a novel approach. We used a cell free system where we could assess direct effects of PKA on human purified channel protein function reconstituted in proteoliposomes. In addition to assessing open probability of channel protein we used semi-quantitative fluorescent phosphoprotein detection and MS/MS mass spectrometry analysis to demonstrate the PKA specificity of the site. Robust increases in frequency of channel openings were recorded after phosphorylation of the long and short N terminal isoforms and the channel protein with C terminus truncated at aa1504. A protein kinase A anchoring protein (AKAP) was not required. We find the novel PKA phosphorylation site at Ser1458 is in close proximity to the Repeat IV S6 region and induces a conformational change in the channel protein that is necessary and sufficient for increased calcium influx through the channel.
Collapse
Affiliation(s)
| | - Padmapriya Muralidharan
- School of Human Sciences, University of Western Australia, Crawley, Western Australia, Australia
| | - Evan Ingley
- Harry Perkins Institute of Medical Research and Centre for Medical Research, University of Western Australia, Nedlands, Western Australia, Australia.,School of Veterinary and Life Sciences, Murdoch University, Murdoch, Western Australia, Australia
| | - Jakob Petereit
- ARC Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia, Australia
| | - A Harvey Millar
- ARC Centre of Excellence in Plant Energy Biology, University of Western Australia, Crawley, Western Australia, Australia
| | - Livia C Hool
- School of Human Sciences, University of Western Australia, Crawley, Western Australia, Australia. .,Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia.
| |
Collapse
|
35
|
Stefan E, Troppmair J, Bister K. Targeting the Architecture of Deregulated Protein Complexes in Cancer. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2017; 111:101-132. [PMID: 29459029 DOI: 10.1016/bs.apcsb.2017.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The architectures of central signaling hubs are precisely organized by static and dynamic protein-protein interactions (PPIs). Upon deregulation, these PPI platforms are capable to propagate or initiate pathophysiological signaling events. This causes the acquisition of molecular features contributing to the etiology or progression of many diseases, including cancer, where deregulated molecular interactions of signaling proteins have been best studied. The reasons for PPI-dependent reprogramming of cancer-initiating cells are manifold; in many cases, mutations perturb PPIs, enzyme activities, protein abundance, or protein localization. Consequently, the pharmaceutical targeting of PPIs promises to be of remarkable therapeutic value. For this review we have selected three key players of oncogenic signaling which are differently affected by PPI deregulation: two (the small G proteins of the RAS family and the transcription factor MYC) are considered "undruggable" using classical drug discovery approaches and in the case of the third protein discussed here, PKA, standard kinase inhibitors, may be unsuitable in the clinic. These circumstances require alternative strategies, which may lie in pharmaceutical drug interference of critical PPIs accountable for oncogenic signaling.
Collapse
Affiliation(s)
- Eduard Stefan
- Institute of Biochemistry and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria.
| | - Jakob Troppmair
- Daniel Swarovski Research Laboratory, Medical University of Innsbruck, Innsbruck, Austria
| | - Klaus Bister
- Institute of Biochemistry and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innsbruck, Austria
| |
Collapse
|
36
|
Hajagos-Tóth J, Ducza E, Samavati R, Vari SG, Gaspar R. Obesity in pregnancy: a novel concept on the roles of adipokines in uterine contractility. Croat Med J 2017; 58:96-104. [PMID: 28409493 PMCID: PMC5410735 DOI: 10.3325/cmj.2017.58.96] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Obesity is a global health problem even among pregnant women. Obesity alters quality of labor, such as preterm labor, prolonged labor, and higher oxytocin requirements in pregnant women. The most important factors to play a role in the altered gestational period and serve as drug targets to treat the consequences are female sexual hormones, calcium channels, adrenergic system, oxytocin, and prostaglandins. However, we have limited information about the impact of obesity on the pregnant uterine contractility and gestation time. Adipose tissue, which is the largest endocrine and paracrine organ, especially in obesity, is responsible for the production of adipokines and various cytokines and chemokines, and there are no reliable data available describing the relation between body mass index, glucose intolerance, and adipokines during pregnancy. Recent data suggest that the dysregulation of leptin, adiponectin, and kisspeptin during pregnancy contributes to gestational diabetes mellitus and pre-eclampsia. A preclinical method for obese pregnancy should be developed to clarify the action of adipokines and assess their impact in obesity. The deeper understanding of the adipokines-induced processes in obese pregnancy may be a step closer to the prevention and therapy of preterm delivery or prolonged pregnancy. Gestational weight gain is one of the factors that could influence the prenatal development, birth weight, and adiposity of newborn.
Collapse
Affiliation(s)
| | | | | | | | - Robert Gaspar
- Robert Gaspar, Eotvos Street 6., Szeged, H-6720, Hungary,
| |
Collapse
|
37
|
Torres-Quesada O, Röck R, Stefan E. Systematic Quantification of GPCR/cAMP-Controlled Protein Kinase A Interactions. Horm Metab Res 2017; 49:240-249. [PMID: 28427097 DOI: 10.1055/s-0042-110791] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The diffusible second messenger cyclic AMP (cAMP) originates from multiple G protein-coupled receptor (GPCR) cascades activating the intracellular key effector protein kinase A (PKA). Spatially and temporally restricted cAMP-fluxes are directly sensed by macromolecular PKA complexes. The consequences are alterations of molecular interactions, which lead to activation of compartmentalized PKA phosphotransferase activities, regulating a vast array of cellular functions. To decode cell-type and cell-compartment specific PKA functions, the spatio-temporal dynamics of small molecule:protein interactions, protein:protein interactions (PPIs), cAMP-mobilization, and phosphotransferase activities need to be determined directly in the appropriate cellular context. A collection of cell-based reporters has been developed to either visualize or quantitatively measure kinase activities or PKA complex formation/dissociation. In this review, we list a collection of unimolecular and bimolecular PKA biosensors, followed by the specification of the modular design of a Renilla luciferase based protein-fragment complementation assay (PCA) platform for measuring PKA network interactions. We discuss the application spectrum of the PCA reporter to identify, quantify, and dissect dynamic and transient PKA complexes downstream of specific GPCR activities. We specify the implementation of a PCA PKA platform to systematically quantify the concurrent involvement of receptor-cAMP signaling, post-translational modifications, and kinase subunit mutations/perturbations in PKA activation. The systematic quantification of transient PKA network interactions will contribute to a better understanding how GPCR-recognized input signals are streamlined through the compartmentalized and cAMP-interacting PKA signalosome.
Collapse
Affiliation(s)
- O Torres-Quesada
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - R Röck
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| | - E Stefan
- Institute of Biochemistry and Center for Molecular Biosciences, University of Innsbruck, Innsbruck, Austria
| |
Collapse
|
38
|
Halls ML, Cooper DMF. Adenylyl cyclase signalling complexes - Pharmacological challenges and opportunities. Pharmacol Ther 2017; 172:171-180. [PMID: 28132906 DOI: 10.1016/j.pharmthera.2017.01.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Signalling pathways involving the vital second messanger, cAMP, impact on most significant physiological processes. Unsurprisingly therefore, the activation and regulation of cAMP signalling is tightly controlled within the cell by processes including phosphorylation, the scaffolding of protein signalling complexes and sub-cellular compartmentalisation. This inherent complexity, along with the highly conserved structure of the catalytic sites among the nine membrane-bound adenylyl cyclases, presents significant challenges for efficient inhibition of cAMP signalling. Here, we will describe the biochemistry and cell biology of the family of membrane-bound adenylyl cyclases, their organisation within the cell, and the nature of the cAMP signals that they produce, as a prelude to considering how cAMP signalling might be perturbed. We describe the limitations associated with direct inhibition of adenylyl cyclase activity, and evaluate alternative strategies for more specific targeting of adenylyl cyclase signalling. The inherent complexity in the activation and organisation of adenylyl cyclase activity may actually provide unique opportunities for selectively targeting discrete adenylyl cyclase functions in disease.
Collapse
Affiliation(s)
- Michelle L Halls
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, 3052, Victoria, Australia
| | - Dermot M F Cooper
- Department of Pharmacology, University of Cambridge, Tennis Court Road, Cambridge CB2 1PD, UK.
| |
Collapse
|
39
|
Bimodal antagonism of PKA signalling by ARHGAP36. Nat Commun 2016; 7:12963. [PMID: 27713425 PMCID: PMC5059767 DOI: 10.1038/ncomms12963] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 08/19/2016] [Indexed: 02/07/2023] Open
Abstract
Protein kinase A is a key mediator of cAMP signalling downstream of G-protein-coupled receptors, a signalling pathway conserved in all eukaryotes. cAMP binding to the regulatory subunits (PKAR) relieves their inhibition of the catalytic subunits (PKAC). Here we report that ARHGAP36 combines two distinct inhibitory mechanisms to antagonise PKA signalling. First, it blocks PKAC activity via a pseudosubstrate motif, akin to the mechanism employed by the protein kinase inhibitor proteins. Second, it targets PKAC for rapid ubiquitin-mediated lysosomal degradation, a pathway usually reserved for transmembrane receptors. ARHGAP36 thus dampens the sensitivity of cells to cAMP. We show that PKA inhibition by ARHGAP36 promotes derepression of the Hedgehog signalling pathway, thereby providing a simple rationale for the upregulation of ARHGAP36 in medulloblastoma. Our work reveals a new layer of PKA regulation that may play an important role in development and disease.
Protein kinase A (PKA) is a key mediator of cyclic AMP signalling. Here, Eccles et al. show that ARHGAP36 antagonizes PKA by acting as a kinase inhibitor and targeting the catalytic subunit for endolysosomal degradation, thus reducing sensitivity of cells to cAMP and promoting Hedgehog signalling.
Collapse
|
40
|
Burgers PP, Bruystens J, Burnley RJ, Nikolaev VO, Keshwani M, Wu J, Janssen BJC, Taylor SS, Heck AJR, Scholten A. Structure of smAKAP and its regulation by PKA-mediated phosphorylation. FEBS J 2016; 283:2132-48. [PMID: 27028580 DOI: 10.1111/febs.13726] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 03/04/2016] [Accepted: 03/29/2016] [Indexed: 12/27/2022]
Abstract
UNLABELLED The A-kinase anchoring protein (AKAP) smAKAP has three extraordinary features; it is very small, it is anchored directly to membranes by acyl motifs, and it interacts almost exclusively with the type I regulatory subunits (RI) of cAMP-dependent kinase (PKA). Here, we determined the crystal structure of smAKAP's A-kinase binding domain (smAKAP-AKB) in complex with the dimerization/docking (D/D) domain of RIα which reveals an extended hydrophobic interface with unique interaction pockets that drive smAKAP's high specificity for RI subunits. We also identify a conserved PKA phosphorylation site at Ser66 in the AKB domain which we predict would cause steric clashes and disrupt binding. This correlates with in vivo colocalization and fluorescence polarization studies, where Ser66 AKB phosphorylation ablates RI binding. Hydrogen/deuterium exchange studies confirm that the AKB helix is accessible and dynamic. Furthermore, full-length smAKAP as well as the unbound AKB is predicted to contain a break at the phosphorylation site, and circular dichroism measurements confirm that the AKB domain loses its helicity following phosphorylation. As the active site of PKA's catalytic subunit does not accommodate α-helices, we predict that the inherent flexibility of the AKB domain enables its phosphorylation by PKA. This represents a novel mechanism, whereby activation of anchored PKA can terminate its binding to smAKAP affecting the regulation of localized cAMP signaling events. DATABASE Structural data are available in the PDB under accession number 5HVZ.
Collapse
Affiliation(s)
- Pepijn P Burgers
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, The Netherlands.,Netherlands Proteomics Centre, Utrecht, The Netherlands
| | - Jessica Bruystens
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, USA
| | - Rebecca J Burnley
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, The Netherlands.,Netherlands Proteomics Centre, Utrecht, The Netherlands
| | | | - Malik Keshwani
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, USA
| | - Jian Wu
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, USA
| | - Bert J C Janssen
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Utrecht University, The Netherlands
| | - Susan S Taylor
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, California, USA.,Department of Pharmacology, University of California San Diego, La Jolla, California, USA.,The Howard Hughes Medical Institute, University of California San Diego, La Jolla, California, USA
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, The Netherlands.,Netherlands Proteomics Centre, Utrecht, The Netherlands
| | - Arjen Scholten
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, The Netherlands.,Netherlands Proteomics Centre, Utrecht, The Netherlands
| |
Collapse
|
41
|
AKAP18:PKA-RIIα structure reveals crucial anchor points for recognition of regulatory subunits of PKA. Biochem J 2016; 473:1881-94. [PMID: 27102985 DOI: 10.1042/bcj20160242] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 04/20/2016] [Indexed: 12/25/2022]
Abstract
A-kinase anchoring proteins (AKAPs) interact with the dimerization/docking (D/D) domains of regulatory subunits of the ubiquitous protein kinase A (PKA). AKAPs tether PKA to defined cellular compartments establishing distinct pools to increase the specificity of PKA signalling. Here, we elucidated the structure of an extended PKA-binding domain of AKAP18β bound to the D/D domain of the regulatory RIIα subunits of PKA. We identified three hydrophilic anchor points in AKAP18β outside the core PKA-binding domain, which mediate contacts with the D/D domain. Such anchor points are conserved within AKAPs that bind regulatory RII subunits of PKA. We derived a different set of anchor points in AKAPs binding regulatory RI subunits of PKA. In vitro and cell-based experiments confirm the relevance of these sites for the interaction of RII subunits with AKAP18 and of RI subunits with the RI-specific smAKAP. Thus we report a novel mechanism governing interactions of AKAPs with PKA. The sequence specificity of each AKAP around the anchor points and the requirement of these points for the tight binding of PKA allow the development of selective inhibitors to unequivocally ascribe cellular functions to the AKAP18-PKA and other AKAP-PKA interactions.
Collapse
|
42
|
Vukićević T, Schulz M, Faust D, Klussmann E. The Trafficking of the Water Channel Aquaporin-2 in Renal Principal Cells-a Potential Target for Pharmacological Intervention in Cardiovascular Diseases. Front Pharmacol 2016; 7:23. [PMID: 26903868 PMCID: PMC4749865 DOI: 10.3389/fphar.2016.00023] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 01/25/2016] [Indexed: 01/13/2023] Open
Abstract
Arginine-vasopressin (AVP) stimulates the redistribution of water channels, aquaporin-2 (AQP2) from intracellular vesicles into the plasma membrane of renal collecting duct principal cells. By this AVP directs 10% of the water reabsorption from the 170 L of primary urine that the human kidneys produce each day. This review discusses molecular mechanisms underlying the AVP-induced redistribution of AQP2; in particular, it provides an overview over the proteins participating in the control of its localization. Defects preventing the insertion of AQP2 into the plasma membrane cause diabetes insipidus. The disease can be acquired or inherited, and is characterized by polyuria and polydipsia. Vice versa, up-regulation of the system causing a predominant localization of AQP2 in the plasma membrane leads to excessive water retention and hyponatremia as in the syndrome of inappropriate antidiuretic hormone secretion (SIADH), late stage heart failure or liver cirrhosis. This article briefly summarizes the currently available pharmacotherapies for the treatment of such water balance disorders, and discusses the value of newly identified mechanisms controlling AQP2 for developing novel pharmacological strategies. Innovative concepts for the therapy of water balance disorders are required as there is a medical need due to the lack of causal treatments.
Collapse
Affiliation(s)
- Tanja Vukićević
- Max Delbrück Center for Molecular Medicine (MDC) in the Helmholtz Association Berlin, Germany
| | - Maike Schulz
- Max Delbrück Center for Molecular Medicine (MDC) in the Helmholtz Association Berlin, Germany
| | - Dörte Faust
- Max Delbrück Center for Molecular Medicine (MDC) in the Helmholtz Association Berlin, Germany
| | - Enno Klussmann
- Max Delbrück Center for Molecular Medicine (MDC) in the Helmholtz AssociationBerlin, Germany; German Centre for Cardiovascular ResearchBerlin, Germany
| |
Collapse
|
43
|
Kennedy EJ, Scott JD. Selective disruption of the AKAP signaling complexes. Methods Mol Biol 2015; 1294:137-50. [PMID: 25783883 DOI: 10.1007/978-1-4939-2537-7_11] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Synthesis of the second messenger cAMP activates a variety of signaling pathways critical for all facets of intracellular regulation. Protein kinase A (PKA) is the major cAMP-responsive effector. Where and when this enzyme is activated has profound implications on the cellular role of PKA. A-Kinase Anchoring Proteins (AKAPs) play a critical role in this process by orchestrating spatial and temporal aspects of PKA action. A popular means of evaluating the impact of these anchored signaling events is to biochemically interfere with the PKA-AKAP interface. Hence, peptide disruptors of PKA anchoring are valuable tools in the investigation of local PKA action. This article outlines the development of PKA isoform-selective disruptor peptides, documents the optimization of cell-soluble peptide derivatives, and introduces alternative cell-based approaches that interrogate other aspects of the PKA-AKAP interface.
Collapse
Affiliation(s)
- Eileen J Kennedy
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia College of Pharmacy, Athens, GA, USA
| | | |
Collapse
|
44
|
Schächterle C, Christian F, Fernandes JMP, Klussmann E. Screening for small molecule disruptors of AKAP-PKA interactions. Methods Mol Biol 2015; 1294:151-66. [PMID: 25783884 DOI: 10.1007/978-1-4939-2537-7_12] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Protein-protein interactions (PPIs) are highly specific and diverse. Their selective inhibition with peptides, peptidomimetics, or small molecules allows determination of functions of individual PPIs. Moreover, inhibition of disease-associated PPIs may lead to new concepts for the treatment of diseases with an unmet medical need. Protein kinase A (PKA) is an ubiquitously expressed protein kinase that controls a plethora of cellular functions. A-kinase anchoring proteins (AKAPs) are multivalent scaffolding proteins that directly interact with PKA. AKAPs spatially and temporally restrict PKA activity to defined cellular compartments and thereby contribute to the specificity of PKA signaling. However, it is largely unknown which of the plethora of PKA-dependent signaling events involve interactions of PKA with AKAPs. Moreover, AKAP-PKA interactions appear to play a role in a variety of cardiovascular, neuronal, and inflammatory diseases, but it is unclear whether these interactions are suitable drug targets. Here we describe an enzyme-linked immunosorbent assay (ELISA) for the screening of small molecule libraries for inhibitors of AKAP-PKA interactions. In addition, we describe a homogenous time-resolved fluorescence (HTRF) assay for use in secondary validation screens. Small molecule inhibitors are invaluable molecular tools for elucidating the functions of AKAP-PKA interactions and may eventually lead to new concepts for the treatment of diseases where AKAP-PKA interactions represent potential drug targets.
Collapse
Affiliation(s)
- Carolin Schächterle
- Max Delbruck Center for Molecular Medicine (MDC) Berlin-Buch, Robert-Rössle-Str. 10, Berlin, 13125, Germany
| | | | | | | |
Collapse
|
45
|
Diviani D, Reggi E, Arambasic M, Caso S, Maric D. Emerging roles of A-kinase anchoring proteins in cardiovascular pathophysiology. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1863:1926-36. [PMID: 26643253 DOI: 10.1016/j.bbamcr.2015.11.024] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 11/20/2015] [Accepted: 11/23/2015] [Indexed: 01/08/2023]
Abstract
Heart and blood vessels ensure adequate perfusion of peripheral organs with blood and nutrients. Alteration of the homeostatic functions of the cardiovascular system can cause hypertension, atherosclerosis, and coronary artery disease leading to heart injury and failure. A-kinase anchoring proteins (AKAPs) constitute a family of scaffolding proteins that are crucially involved in modulating the function of the cardiovascular system both under physiological and pathological conditions. AKAPs assemble multifunctional signaling complexes that ensure correct targeting of the cAMP-dependent protein kinase (PKA) as well as other signaling enzymes to precise subcellular compartments. This allows local regulation of specific effector proteins that control the function of vascular and cardiac cells. This review will focus on recent advances illustrating the role of AKAPs in cardiovascular pathophysiology. The accent will be mainly placed on the molecular events linked to the control of vascular integrity and blood pressure as well as on the cardiac remodeling process associated with heart failure. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.
Collapse
Affiliation(s)
- Dario Diviani
- Département de Pharmacologie et de Toxicologie, Faculté de Biologie et de Médecine, Lausanne 1005, Switzerland.
| | - Erica Reggi
- Département de Pharmacologie et de Toxicologie, Faculté de Biologie et de Médecine, Lausanne 1005, Switzerland
| | - Miroslav Arambasic
- Département de Pharmacologie et de Toxicologie, Faculté de Biologie et de Médecine, Lausanne 1005, Switzerland
| | - Stefania Caso
- Département de Pharmacologie et de Toxicologie, Faculté de Biologie et de Médecine, Lausanne 1005, Switzerland
| | - Darko Maric
- Département de Pharmacologie et de Toxicologie, Faculté de Biologie et de Médecine, Lausanne 1005, Switzerland
| |
Collapse
|
46
|
Dema A, Perets E, Schulz MS, Deák VA, Klussmann E. Pharmacological targeting of AKAP-directed compartmentalized cAMP signalling. Cell Signal 2015; 27:2474-87. [PMID: 26386412 DOI: 10.1016/j.cellsig.2015.09.008] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 09/08/2015] [Accepted: 09/14/2015] [Indexed: 01/26/2023]
Abstract
The second messenger cyclic adenosine monophosphate (cAMP) can bind and activate protein kinase A (PKA). The cAMP/PKA system is ubiquitous and involved in a wide array of biological processes and therefore requires tight spatial and temporal regulation. Important components of the safeguard system are the A-kinase anchoring proteins (AKAPs), a heterogeneous family of scaffolding proteins defined by its ability to directly bind PKA. AKAPs tether PKA to specific subcellular compartments, and they bind further interaction partners to create local signalling hubs. The recent discovery of new AKAPs and advances in the field that shed light on the relevance of these hubs for human disease highlight unique opportunities for pharmacological modulation. This review exemplifies how interference with signalling, particularly cAMP signalling, at such hubs can reshape signalling responses and discusses how this could lead to novel pharmacological concepts for the treatment of disease with an unmet medical need such as cardiovascular disease and cancer.
Collapse
Affiliation(s)
- Alessandro Dema
- Max Delbrück Center for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Ekaterina Perets
- Max Delbrück Center for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Maike Svenja Schulz
- Max Delbrück Center for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Veronika Anita Deák
- Max Delbrück Center for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany
| | - Enno Klussmann
- Max Delbrück Center for Molecular Medicine Berlin in the Helmholtz Association (MDC), Robert-Rössle-Straße 10, 13125 Berlin, Germany; DZHK, German Centre for Cardiovascular Research, Oudenarder Straße 16, 13347 Berlin, Germany.
| |
Collapse
|
47
|
Calejo AI, Taskén K. Targeting protein-protein interactions in complexes organized by A kinase anchoring proteins. Front Pharmacol 2015; 6:192. [PMID: 26441649 PMCID: PMC4562273 DOI: 10.3389/fphar.2015.00192] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 08/24/2015] [Indexed: 01/06/2023] Open
Abstract
Cyclic AMP is a ubiquitous intracellular second messenger involved in the regulation of a wide variety of cellular processes, a majority of which act through the cAMP – protein kinase A (PKA) signaling pathway and involve PKA phosphorylation of specific substrates. PKA phosphorylation events are typically spatially restricted and temporally well controlled. A-kinase anchoring proteins (AKAPs) directly bind PKA and recruit it to specific subcellular loci targeting the kinase activity toward particular substrates, and thereby provide discrete spatiotemporal control of downstream phosphorylation events. AKAPs also scaffold other signaling molecules into multi-protein complexes that function as crossroads between different signaling pathways. Targeting AKAP coordinated protein complexes with high-affinity peptidomimetics or small molecules to tease apart distinct protein–protein interactions (PPIs) therefore offers important means to disrupt binding of specific components of the complex to better understand the molecular mechanisms involved in the function of individual signalosomes and their pathophysiological role. Furthermore, development of novel classes of small molecules involved in displacement of AKAP-bound signal molecules is now emerging. Here, we will focus on mechanisms for targeting PPI, disruptors that modulate downstream cAMP signaling and their role, especially in the heart.
Collapse
Affiliation(s)
- Ana I Calejo
- Biotechnology Centre, University of Oslo Oslo, Norway ; Centre for Molecular Medicine Norway, Nordic European Molecular Biology Laboratory Partnership, University of Oslo and Oslo University Hospital Oslo, Norway
| | - Kjetil Taskén
- Biotechnology Centre, University of Oslo Oslo, Norway ; Centre for Molecular Medicine Norway, Nordic European Molecular Biology Laboratory Partnership, University of Oslo and Oslo University Hospital Oslo, Norway
| |
Collapse
|
48
|
Raslan Z, Magwenzi S, Aburima A, Taskén K, Naseem KM. Targeting of type I protein kinase A to lipid rafts is required for platelet inhibition by the 3',5'-cyclic adenosine monophosphate-signaling pathway. J Thromb Haemost 2015; 13:1721-34. [PMID: 26176741 DOI: 10.1111/jth.13042] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 06/18/2015] [Indexed: 01/14/2023]
Abstract
BACKGROUND Platelet adhesion to von Willebrand factor (VWF) is modulated by 3',5'-cyclic adenosine monophosphate (cAMP) signaling through protein kinase A (PKA)-mediated phosphorylation of glycoprotein (GP)Ibβ. A-kinase anchoring proteins (AKAPs) are proposed to control the localization and substrate specificity of individual PKA isoforms. However, the role of PKA isoforms in regulating the phosphorylation of GPIbβ and platelet response to VWF is unknown. OBJECTIVES We wished to determine the role of PKA isoforms in the phosphorylation of GPIbβ and platelet activation by VWF as a model for exploring the selective partitioning of cAMP signaling in platelets. RESULTS The two isoforms of PKA in platelets, type I (PKA-I) and type II (PKA-II), were differentially localized, with a small pool of PKA-I found in lipid rafts. Using a combination of Far Western blotting, immunoprecipitation, proximity ligation assay and cAMP pull-down we identified moesin as an AKAP that potentially localizes PKA-I to rafts. Introduction of cell-permeable anchoring disruptor peptide, RI anchoring disruptor (RIAD-Arg11 ), to block PKA-I/AKAP interactions, uncoupled PKA-RI from moesin, displaced PKA-RI from rafts and reduced kinase activity in rafts. Examination of GPIbβ demonstrated that it was phosphorylated in response to low concentrations of PGI2 in a PKA-dependent manner and occurred primarily in lipid raft fractions. RIAD-Arg11 caused a significant reduction in raft-localized phosphoGPIbβ and diminished the ability of PGI2 to regulate VWF-mediated aggregation and thrombus formation in vitro. CONCLUSION We propose that PKA-I-specific AKAPs in platelets, including moesin, organize a selective localization of PKA-I required for phosphorylation of GPIbβ and contribute to inhibition of platelet VWF interactions.
Collapse
Affiliation(s)
- Z Raslan
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, UK
| | - S Magwenzi
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, UK
| | - A Aburima
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, UK
| | - K Taskén
- Biotechnology Centre of Oslo, University of Oslo, Oslo, Norway
- K.G. Jebsen Inflammation Research Centre, University of Oslo, Oslo, Norway
- Centre for Molecular Medicine Norway, Nordic EMBL Partnership, University of Oslo and Oslo University Hospital, Oslo, Norway
- Department of Infectious Diseases, Oslo University Hospital, Oslo, Norway
| | - K M Naseem
- Centre for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, UK
| |
Collapse
|
49
|
Nygren PJ, Scott JD. Therapeutic strategies for anchored kinases and phosphatases: exploiting short linear motifs and intrinsic disorder. Front Pharmacol 2015; 6:158. [PMID: 26283967 PMCID: PMC4516873 DOI: 10.3389/fphar.2015.00158] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 07/16/2015] [Indexed: 12/17/2022] Open
Abstract
Phosphorylation events that occur in response to the second messenger cAMP are controlled spatially and temporally by protein kinase A (PKA) interacting with A-kinase anchoring proteins (AKAPs). Recent advances in understanding the structural basis for this interaction have reinforced the hypothesis that AKAPs create spatially constrained signaling microdomains. This has led to the realization that the PKA/AKAP interface is a potential drug target for modulating a plethora of cell-signaling events. Pharmacological disruption of kinase–AKAP interactions has previously been explored for disease treatment and remains an interesting area of research. However, disrupting or enhancing the association of phosphatases with AKAPs is a therapeutic concept of equal promise, particularly since they oppose the actions of many anchored kinases. Accordingly, numerous AKAPs bind phosphatases such as protein phosphatase 1 (PP1), calcineurin (PP2B), and PP2A. These multimodal signaling hubs are equally able to control the addition of phosphate groups onto target substrates, as well as the removal of these phosphate groups. In this review, we describe recent advances in structural analysis of kinase and phosphatase interactions with AKAPs, and suggest future possibilities for targeting these interactions for therapeutic benefit.
Collapse
Affiliation(s)
- Patrick J Nygren
- Department of Pharmacology, University of Washington Seattle, WA, USA ; Howard Hughes Medical Institute Chevy Chase, MD, USA
| | - John D Scott
- Department of Pharmacology, University of Washington Seattle, WA, USA ; Howard Hughes Medical Institute Chevy Chase, MD, USA
| |
Collapse
|
50
|
Maass PG, Aydin A, Luft FC, Schächterle C, Weise A, Stricker S, Lindschau C, Vaegler M, Qadri F, Toka HR, Schulz H, Krawitz PM, Parkhomchuk D, Hecht J, Hollfinger I, Wefeld-Neuenfeld Y, Bartels-Klein E, Mühl A, Kann M, Schuster H, Chitayat D, Bialer MG, Wienker TF, Ott J, Rittscher K, Liehr T, Jordan J, Plessis G, Tank J, Mai K, Naraghi R, Hodge R, Hopp M, Hattenbach LO, Busjahn A, Rauch A, Vandeput F, Gong M, Rüschendorf F, Hübner N, Haller H, Mundlos S, Bilginturan N, Movsesian MA, Klussmann E, Toka O, Bähring S. PDE3A mutations cause autosomal dominant hypertension with brachydactyly. Nat Genet 2015; 47:647-53. [PMID: 25961942 DOI: 10.1038/ng.3302] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 04/17/2015] [Indexed: 01/02/2023]
Abstract
Cardiovascular disease is the most common cause of death worldwide, and hypertension is the major risk factor. Mendelian hypertension elucidates mechanisms of blood pressure regulation. Here we report six missense mutations in PDE3A (encoding phosphodiesterase 3A) in six unrelated families with mendelian hypertension and brachydactyly type E (HTNB). The syndrome features brachydactyly type E (BDE), severe salt-independent but age-dependent hypertension, an increased fibroblast growth rate, neurovascular contact at the rostral-ventrolateral medulla, altered baroreflex blood pressure regulation and death from stroke before age 50 years when untreated. In vitro analyses of mesenchymal stem cell-derived vascular smooth muscle cells (VSMCs) and chondrocytes provided insights into molecular pathogenesis. The mutations increased protein kinase A-mediated PDE3A phosphorylation and resulted in gain of function, with increased cAMP-hydrolytic activity and enhanced cell proliferation. Levels of phosphorylated VASP were diminished, and PTHrP levels were dysregulated. We suggest that the identified PDE3A mutations cause the syndrome. VSMC-expressed PDE3A deserves scrutiny as a therapeutic target for the treatment of hypertension.
Collapse
Affiliation(s)
- Philipp G Maass
- 1] Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [2] Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Atakan Aydin
- 1] Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [2] Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Friedrich C Luft
- 1] Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [2] Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [3] Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Carolin Schächterle
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Anja Weise
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Sigmar Stricker
- 1] Max Planck Institute for Molecular Genetics, Berlin, Germany. [2] Institute for Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Carsten Lindschau
- 1] Department of Nephrology, Hannover University Medical School, Hannover, Germany. [2] Staatliche Technikerschule Berlin, Berlin, Germany
| | - Martin Vaegler
- 1] Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [2] Department of Urology, Laboratory of Tissue Engineering, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Fatimunnisa Qadri
- 1] Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [2] Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Hakan R Toka
- 1] Division of Nephrology and Hypertension, Eastern Virginia Medical School, Norfolk, Virginia, USA. [2] Division of Nephrology, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Herbert Schulz
- 1] Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [2] Cologne Center for Genomics (CCG), University of Cologne, Cologne, Germany
| | - Peter M Krawitz
- 1] Max Planck Institute for Molecular Genetics, Berlin, Germany. [2] Institute for Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, Berlin, Germany. [3] Berlin Brandenburg Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Dmitri Parkhomchuk
- 1] Max Planck Institute for Molecular Genetics, Berlin, Germany. [2] Institute for Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, Berlin, Germany. [3] Berlin Brandenburg Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Jochen Hecht
- 1] Max Planck Institute for Molecular Genetics, Berlin, Germany. [2] Berlin Brandenburg Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Irene Hollfinger
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Yvette Wefeld-Neuenfeld
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Eireen Bartels-Klein
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Astrid Mühl
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Martin Kann
- 1] Department II of Medicine, University of Cologne, Cologne, Germany. [2] Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | | | - David Chitayat
- 1] Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada. [2] Prenatal Diagnosis and Medical Genetics Program, Department of Obstetrics and Gynecology, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada
| | - Martin G Bialer
- 1] Division of Medical Genetics, North Shore/LIJ Health System, Manhasset, New York, USA. [2] Department of Pediatrics, North Shore/LIJ Health System, Manhasset, New York, USA
| | - Thomas F Wienker
- 1] Max Planck Institute for Molecular Genetics, Berlin, Germany. [2] Institute for Medical Biometry, Informatics and Epidemiology, University of Bonn, Bonn, Germany
| | - Jürg Ott
- 1] Institute of Psychology, Chinese Academy of Sciences, Beijing, China. [2] Statistical Genetics, Rockefeller University, New York, New York, USA
| | - Katharina Rittscher
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Thomas Liehr
- Institute of Human Genetics, Jena University Hospital, Friedrich Schiller University, Jena, Germany
| | - Jens Jordan
- Institute of Clinical Pharmacology, Hannover Medical School, Hannover, Germany
| | - Ghislaine Plessis
- Centre Hospitalier Universitaire de Caen, Cytogénétique Postnatale et Génétique Clinique, Caen, France
| | - Jens Tank
- Institute of Clinical Pharmacology, Hannover Medical School, Hannover, Germany
| | - Knut Mai
- Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Ramin Naraghi
- Department of Neurosurgery, Bundeswehrkrankenhaus Ulm, Ulm, Germany
| | - Russell Hodge
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Maxwell Hopp
- Department of Pediatrics, Griffith Base Hospital, Griffith, New South Wales, Australia
| | - Lars O Hattenbach
- Department of Ophthalmology, Hospital Ludwigshafen, Ludwigshafen, Germany
| | | | - Anita Rauch
- Institute for Medical Genetics, University of Zurich, Zurich, Switzerland
| | - Fabrice Vandeput
- 1] Cardiology Section, Veterans Affairs Salt Lake City Health Care System, Salt Lake City, Utah, USA. [2] Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA. [3] Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah, USA
| | - Maolian Gong
- 1] Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [2] Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Franz Rüschendorf
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Norbert Hübner
- 1] Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [2] DZHK (German Centre for Cardiovascular Research), Berlin, Germany. [3] Charité Universitätsmedizin, Berlin, Germany
| | - Hermann Haller
- Department of Nephrology, Hannover University Medical School, Hannover, Germany
| | - Stefan Mundlos
- 1] Max Planck Institute for Molecular Genetics, Berlin, Germany. [2] Institute for Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, Berlin, Germany. [3] Berlin Brandenburg Center for Regenerative Therapies (BCRT), Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Nihat Bilginturan
- Department of Pediatric Oncology, Hacettepe University, Ankara, Turkey
| | - Matthew A Movsesian
- 1] Cardiology Section, Veterans Affairs Salt Lake City Health Care System, Salt Lake City, Utah, USA. [2] Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA. [3] Department of Pharmacology and Toxicology, University of Utah, Salt Lake City, Utah, USA
| | - Enno Klussmann
- 1] Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [2] DZHK (German Centre for Cardiovascular Research), Berlin, Germany
| | - Okan Toka
- Department of Pediatric Cardiology, Children's Hospital, Friedrich Alexander University Erlangen, Erlangen, Germany
| | - Sylvia Bähring
- 1] Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany. [2] Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| |
Collapse
|