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Paudel S, Yue M, Nalamalapu R, Saha MS. Deciphering the Calcium Code: A Review of Calcium Activity Analysis Methods Employed to Identify Meaningful Activity in Early Neural Development. Biomolecules 2024; 14:138. [PMID: 38275767 PMCID: PMC10813340 DOI: 10.3390/biom14010138] [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: 12/14/2023] [Revised: 01/16/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024] Open
Abstract
The intracellular and intercellular flux of calcium ions represents an ancient and universal mode of signaling that regulates an extensive array of cellular processes. Evidence for the central role of calcium signaling includes various techniques that allow the visualization of calcium activity in living cells. While extensively investigated in mature cells, calcium activity is equally important in developing cells, particularly the embryonic nervous system where it has been implicated in a wide variety array of determinative events. However, unlike in mature cells, where the calcium dynamics display regular, predictable patterns, calcium activity in developing systems is far more sporadic, irregular, and diverse. This renders the ability to assess calcium activity in a consistent manner extremely challenging, challenges reflected in the diversity of methods employed to analyze calcium activity in neural development. Here we review the wide array of calcium detection and analysis methods used across studies, limiting the extent to which they can be comparatively analyzed. The goal is to provide investigators not only with an overview of calcium activity analysis techniques currently available, but also to offer suggestions for future work and standardization to enable informative comparative evaluations of this fundamental and important process in neural development.
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Affiliation(s)
- Sudip Paudel
- Wyss Institute, Harvard University, Boston, MA 02215, USA; (S.P.); (M.Y.)
| | - Michelle Yue
- Wyss Institute, Harvard University, Boston, MA 02215, USA; (S.P.); (M.Y.)
| | - Rithvik Nalamalapu
- School of Medicine, Virginia Commonwealth University, Richmond, VA 23298, USA;
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2
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Urrutia PJ, González-Billault C. A Role for Second Messengers in Axodendritic Neuronal Polarity. J Neurosci 2023; 43:2037-2052. [PMID: 36948585 PMCID: PMC10039749 DOI: 10.1523/jneurosci.1065-19.2023] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 02/07/2023] [Accepted: 02/10/2023] [Indexed: 03/24/2023] Open
Abstract
Neuronal polarization is a complex molecular process regulated by intrinsic and extrinsic mechanisms. Nerve cells integrate multiple extracellular cues to generate intracellular messengers that ultimately control cell morphology, metabolism, and gene expression. Therefore, second messengers' local concentration and temporal regulation are crucial elements for acquiring a polarized morphology in neurons. This review article summarizes the main findings and current understanding of how Ca2+, IP3, cAMP, cGMP, and hydrogen peroxide control different aspects of neuronal polarization, and highlights questions that still need to be resolved to fully understand the fascinating cellular processes involved in axodendritic polarization.
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Affiliation(s)
- Pamela J Urrutia
- Department of Biology, Faculty of Sciences, Universidad de Chile, Santiago, Chile 7800003
- School of Medical Technology, Faculty of Medicine and Science, Universidad San Sebastián, Santiago, Chile 7510157
| | - Christian González-Billault
- Department of Biology, Faculty of Sciences, Universidad de Chile, Santiago, Chile 7800003
- Department of Neurosciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile 8380453
- Geroscience Center for Brain Health and Metabolism, Santiago, Chile 7800003
- Buck Institute for Research on Aging, Novato, California 94945
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3
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Klaver D, Gander H, Dobler G, Rahm A, Thurnher M. The P2Y11 receptor of human M2 macrophages activates canonical and IL-1 receptor signaling to translate the extracellular danger signal ATP into anti-inflammatory and pro-angiogenic responses. Cell Mol Life Sci 2022; 79:519. [PMID: 36107259 PMCID: PMC9476423 DOI: 10.1007/s00018-022-04548-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 08/22/2022] [Accepted: 09/04/2022] [Indexed: 11/25/2022]
Abstract
The cytoprotective ATP receptor P2Y11 is upregulated during M2 macrophage differentiation and contributes to the anti-inflammatory properties of this macrophage subset. Here, we studied P2Y11-induced reprogramming of human M2 macrophages at the level of mRNA and protein expression. Upregulation of IL-1 receptor (IL-1R) and its known downstream effectors VEGF, CCL20 and SOCS3 as well as downregulation of the ATP-degrading ecto-ATPase CD39 emerged as hallmarks of P2Y11 activation. The anti-inflammatory signature of the P2Y11 transcriptome was further characterized by the downregulation of P2RX7, toll-like receptors and inflammasome components. P2Y11-induced IL-1R upregulation formed the basis for reinforced IL-1 responsiveness of activated M2 macrophages, as IL-1α and IL-1ß each enhanced P2Y11-induced secretion of VEGF and CCL20 as well as the previously reported shedding of soluble tumor necrosis factor receptor 2 (sTNFR2). Raising intracellular cyclic AMP (cAMP) in M2 macrophages through phosphodiesterase 4 inhibition enhanced P2Y11-driven responses. The cAMP-binding effector, exchange protein activated by cAMP 1 (Epac1), which is known to induce SOCS3, differentially regulated the P2Y11/IL-1R response because pharmacological Epac1 inhibition enhanced sTNFR2 and CCL20 release, but had no effect on VEGF secretion. In addition to cAMP, calcium and protein kinase C participated in P2Y11 signaling. Our study reveals how P2Y11 harnesses canonical and IL-1R signaling to promote an anti-inflammatory and pro-angiogenic switch of human M2 macrophages, which may be controlled in part by an Epac1-SOCS3 axis.
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Affiliation(s)
- Dominik Klaver
- Immunotherapy Unit, Department of Urology, Medical University of Innsbruck, Innrain 66a, 6020, Innsbruck, Austria
| | - Hubert Gander
- Immunotherapy Unit, Department of Urology, Medical University of Innsbruck, Innrain 66a, 6020, Innsbruck, Austria
| | - Gabriele Dobler
- Immunotherapy Unit, Department of Urology, Medical University of Innsbruck, Innrain 66a, 6020, Innsbruck, Austria
| | - Andrea Rahm
- Immunotherapy Unit, Department of Urology, Medical University of Innsbruck, Innrain 66a, 6020, Innsbruck, Austria
| | - Martin Thurnher
- Immunotherapy Unit, Department of Urology, Medical University of Innsbruck, Innrain 66a, 6020, Innsbruck, Austria.
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4
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Linghu C, Johnson SL, Valdes PA, Shemesh OA, Park WM, Park D, Piatkevich KD, Wassie AT, Liu Y, An B, Barnes SA, Celiker OT, Yao CC, Yu CCJ, Wang R, Adamala KP, Bear MF, Keating AE, Boyden ES. Spatial Multiplexing of Fluorescent Reporters for Imaging Signaling Network Dynamics. Cell 2020; 183:1682-1698.e24. [PMID: 33232692 DOI: 10.1016/j.cell.2020.10.035] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 10/05/2020] [Accepted: 10/21/2020] [Indexed: 12/23/2022]
Abstract
In order to analyze how a signal transduction network converts cellular inputs into cellular outputs, ideally one would measure the dynamics of many signals within the network simultaneously. We found that, by fusing a fluorescent reporter to a pair of self-assembling peptides, it could be stably clustered within cells at random points, distant enough to be resolved by a microscope but close enough to spatially sample the relevant biology. Because such clusters, which we call signaling reporter islands (SiRIs), can be modularly designed, they permit a set of fluorescent reporters to be efficiently adapted for simultaneous measurement of multiple nodes of a signal transduction network within single cells. We created SiRIs for indicators of second messengers and kinases and used them, in hippocampal neurons in culture and intact brain slices, to discover relationships between the speed of calcium signaling, and the amplitude of PKA signaling, upon receiving a cAMP-driving stimulus.
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Affiliation(s)
- Changyang Linghu
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA 02139, USA
| | - Shannon L Johnson
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA
| | - Pablo A Valdes
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; Department of Neurosurgery, Harvard Medical School, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Or A Shemesh
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Department of Neurobiology and Pittsburgh Institute for Neurodegenerative Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | - Won Min Park
- Tim Taylor Department of Chemical Engineering, Kansas State University, Manhattan, KS 66506, USA
| | - Demian Park
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA
| | - Kiryl D Piatkevich
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; School of Life Sciences, Westlake University, Hangzhou, Zhejiang 310024, China
| | - Asmamaw T Wassie
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA
| | - Yixi Liu
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA
| | - Bobae An
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA
| | - Stephanie A Barnes
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Picower Institute for Learning and Memory, MIT, Cambridge, MA 02139, USA
| | - Orhan T Celiker
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA 02139, USA
| | - Chun-Chen Yao
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA
| | - Chih-Chieh Jay Yu
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA
| | - Ru Wang
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA
| | - Katarzyna P Adamala
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Mark F Bear
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Picower Institute for Learning and Memory, MIT, Cambridge, MA 02139, USA
| | - Amy E Keating
- Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biology, MIT, Cambridge, MA 02139, USA; Koch Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Edward S Boyden
- Department of Media Arts and Sciences, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA; McGovern Institute for Brain Research, MIT, Cambridge, MA 02139, USA; Center for Neurobiological Engineering, MIT, Cambridge, MA 02139, USA; Department of Biological Engineering, MIT, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, USA; Koch Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Cambridge, MA 02139, USA.
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5
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Beltran CGG, Coyne VE. iTRAQ-based quantitative proteomic profiling of the immune response of the South African abalone, Haliotis midae. FISH & SHELLFISH IMMUNOLOGY 2020; 99:130-143. [PMID: 32045637 DOI: 10.1016/j.fsi.2020.02.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 01/30/2020] [Accepted: 02/03/2020] [Indexed: 06/10/2023]
Abstract
The South African abalone Haliotis midae is a commercially important species farmed at high densities in land-based aquaculture systems. Disease outbreaks have had a severe financial impact on the abalone industry yet the molecular mechanisms underlying the immune response of H. midae remain obscure. In this study, a comparative shotgun proteomics approach using iTRAQ coupled with LC-MS/MS was employed to investigate H. midae proteome changes in response to Vibrio anguillarum challenge. A total of 118 non-redundant, unique haemocyte proteins were identified and quantified, with 16 proteins significantly regulated. Hierarchical clustering and pathway analysis uncovered a coordinated response dominated by calcium and cAMP signalling via activation of MAPK cascades. Early up-regulated biological processes involve phagocytosis, nitric oxide production and ATP-synthesis, whilst down-regulated responses were predominantly involved in the regulation of apoptosis. The late up-regulated response involved protein kinase activity and detoxification processes. Expression of selected proteins was validated by Western blot. A putative allograft inflammatory factor-1 protein was further selected to establish its functional molecular role in haemocytes. Confocal imaging revealed that allograft inflammatory factor-1 regulates phagocytosis via a functional interaction with filamentous actin. This is the first time a high-throughput proteomics approach has been used to investigate the immune response of H. midae.
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Affiliation(s)
- Caroline G G Beltran
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7700, South Africa
| | - Vernon E Coyne
- Department of Molecular and Cell Biology, University of Cape Town, Rondebosch, 7700, South Africa.
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6
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A ghrelin receptor and oxytocin receptor heterocomplex impairs oxytocin mediated signalling. Neuropharmacology 2019; 152:90-101. [DOI: 10.1016/j.neuropharm.2018.12.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 11/21/2018] [Accepted: 12/18/2018] [Indexed: 12/31/2022]
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7
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King JR, Kabbani N. Alpha 7 nicotinic receptors attenuate neurite development through calcium activation of calpain at the growth cone. PLoS One 2018; 13:e0197247. [PMID: 29768467 PMCID: PMC5955587 DOI: 10.1371/journal.pone.0197247] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 04/30/2018] [Indexed: 11/18/2022] Open
Abstract
The α7 nicotinic acetylcholine receptor (nAChR) is a ligand-gated ion channel that plays an important role in cellular calcium signaling contributing to synaptic development and plasticity, and is a key drug target for the treatment of neurodegenerative conditions such as Alzheimer's disease. Here we show that α7 nAChR mediated calcium signals in differentiating PC12 cells activate the proteolytic enzyme calpain leading to spectrin breakdown, microtubule retraction, and attenuation in neurite growth. Imaging in growth cones confirms that α7 activation decreases EB3 comet motility in a calcium dependent manner as demonstrated by the ability of α7 nAChR, ryanodine, or IP3 receptor antagonists to block the effect of α7 nAChR on growth. α7 nAChR mediated EB3 comet motility, spectrin breakdown, and neurite growth was also inhibited by the addition of the selective calpain blocker calpeptin and attenuated by the expression of an α7 subunit unable to bind Gαq and activate calcium store release. The findings indicate that α7 nAChRs regulate cytoskeletal dynamics through local calcium signals for calpain protease activity.
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Affiliation(s)
- Justin R. King
- School of Systems Biology, George Mason University, Fairfax, Virginia, United States of America
| | - Nadine Kabbani
- School of Systems Biology, George Mason University, Fairfax, Virginia, United States of America
- * E-mail:
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8
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Kabbani N, Nichols RA. Beyond the Channel: Metabotropic Signaling by Nicotinic Receptors. Trends Pharmacol Sci 2018; 39:354-366. [PMID: 29428175 DOI: 10.1016/j.tips.2018.01.002] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 01/05/2018] [Accepted: 01/08/2018] [Indexed: 01/01/2023]
Abstract
The α7 nicotinic acetylcholine receptor (nAChR) is a ligand-gated ion channel (LGIC) that plays an important role in cellular calcium signaling and contributes to several neurological diseases. Agonist binding to the α7 nAChR induces fast channel activation followed by inactivation and prolonged desensitization while triggering long-lasting calcium signaling. These activities foster neurotransmitter release, synaptic plasticity, and somatodendritic regulation in the brain. We discuss here the ability of α7 nAChRs to operate in ionotropic (α7i) and metabotropic (α7m) modes, leading to calcium-induced calcium release (CICR) and G protein-associated inositol trisphosphate (IP3)-induced calcium release (IICR), respectively. Metabotropic activity extends the spatial and temporal aspects of calcium signaling by the α7 channel beyond its ionotropic limits, persisting into the desensitized state. Delineation of the ionotropic and metabotropic properties of the α7 nAChR will provide definitive indicators of moment-to-moment receptor functional status that will, in turn, spearhead new drug development.
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Affiliation(s)
- Nadine Kabbani
- School of Systems Biology, George Mason University, Manassas, VA 20110, USA.
| | - Robert A Nichols
- Department of Cell and Molecular Biology, University of Hawai'i at Manoa, Honolulu, HI 96813, USA
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9
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Zhang F, Tzanakakis ES. Optogenetic regulation of insulin secretion in pancreatic β-cells. Sci Rep 2017; 7:9357. [PMID: 28839233 PMCID: PMC5571193 DOI: 10.1038/s41598-017-09937-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 08/01/2017] [Indexed: 02/06/2023] Open
Abstract
Pancreatic β-cell insulin production is orchestrated by a complex circuitry involving intracellular elements including cyclic AMP (cAMP). Tackling aberrations in glucose-stimulated insulin release such as in diabetes with pharmacological agents, which boost the secretory capacity of β-cells, is linked to adverse side effects. We hypothesized that a photoactivatable adenylyl cyclase (PAC) can be employed to modulate cAMP in β-cells with light thereby enhancing insulin secretion. To that end, the PAC gene from Beggiatoa (bPAC) was delivered to β-cells. A cAMP increase was noted within 5 minutes of photostimulation and a significant drop at 12 minutes post-illumination. The concomitant augmented insulin secretion was comparable to that from β-cells treated with secretagogues. Greater insulin release was also observed over repeated cycles of photoinduction without adverse effects on viability and proliferation. Furthermore, the expression and activation of bPAC increased cAMP and insulin secretion in murine islets and in β-cell pseudoislets, which displayed a more pronounced light-triggered hormone secretion compared to that of β-cell monolayers. Calcium channel blocking curtailed the enhanced insulin response due to bPAC activity. This optogenetic system with modulation of cAMP and insulin release can be employed for the study of β-cell function and for enabling new therapeutic modalities for diabetes.
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Affiliation(s)
- Fan Zhang
- Department of Chemical and Biological Engineering, Tufts University, Medford, MA, 02155, USA.
| | - Emmanuel S Tzanakakis
- Department of Chemical and Biological Engineering, Tufts University, Medford, MA, 02155, USA. .,Clinical and Translational Science Institute, Tufts Medical Center, Boston, MA, 02111, USA.
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10
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Torres-Quesada O, Mayrhofer JE, Stefan E. The many faces of compartmentalized PKA signalosomes. Cell Signal 2017; 37:1-11. [PMID: 28528970 DOI: 10.1016/j.cellsig.2017.05.012] [Citation(s) in RCA: 119] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 05/16/2017] [Accepted: 05/17/2017] [Indexed: 01/03/2023]
Abstract
Cellular signal transmission requires the dynamic formation of spatiotemporally controlled molecular interactions. At the cell surface information is received by receptor complexes and relayed through intracellular signaling platforms which organize the actions of functionally interacting signaling enzymes and substrates. The list of hormone or neurotransmitter pathways that utilize the ubiquitous cAMP-sensing protein kinase A (PKA) system is expansive. This requires that the specificity, duration, and intensity of PKA responses are spatially and temporally restricted. Hereby, scaffolding proteins take the center stage for ensuring proper signal transmission. They unite second messenger sensors, activators, effectors, and kinase substrates within cellular micro-domains to precisely control and route signal propagation. A-kinase anchoring proteins (AKAPs) organize such subcellular signalosomes by tethering the PKA holoenzyme to distinct cell compartments. AKAPs differ in their modular organization showing pathway specific arrangements of interaction motifs or domains. This enables the cell- and compartment- guided assembly of signalosomes with unique enzyme composition and function. The AKAP-mediated clustering of cAMP and other second messenger sensing and interacting signaling components along with functional successive enzymes facilitates the rapid and precise dissemination of incoming signals. This review article delineates examples for different means of PKA regulation and for snapshots of compartmentalized PKA signalosomes.
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Affiliation(s)
- Omar Torres-Quesada
- Institute of Biochemistry and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Johanna E Mayrhofer
- Institute of Biochemistry and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Eduard Stefan
- Institute of Biochemistry and Center for Molecular Biosciences Innsbruck, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
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11
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Carrisoza-Gaytan R, Carattino MD, Kleyman TR, Satlin LM. An unexpected journey: conceptual evolution of mechanoregulated potassium transport in the distal nephron. Am J Physiol Cell Physiol 2015; 310:C243-59. [PMID: 26632600 DOI: 10.1152/ajpcell.00328.2015] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Flow-induced K secretion (FIKS) in the aldosterone-sensitive distal nephron (ASDN) is mediated by large-conductance, Ca(2+)/stretch-activated BK channels composed of pore-forming α-subunits (BKα) and accessory β-subunits. This channel also plays a critical role in the renal adaptation to dietary K loading. Within the ASDN, the cortical collecting duct (CCD) is a major site for the final renal regulation of K homeostasis. Principal cells in the ASDN possess a single apical cilium whereas the surfaces of adjacent intercalated cells, devoid of cilia, are decorated with abundant microvilli and microplicae. Increases in tubular (urinary) flow rate, induced by volume expansion, diuretics, or a high K diet, subject CCD cells to hydrodynamic forces (fluid shear stress, circumferential stretch, and drag/torque on apical cilia and presumably microvilli/microplicae) that are transduced into increases in principal (PC) and intercalated (IC) cell cytoplasmic Ca(2+) concentration that activate apical voltage-, stretch- and Ca(2+)-activated BK channels, which mediate FIKS. This review summarizes studies by ourselves and others that have led to the evolving picture that the BK channel is localized in a macromolecular complex at the apical membrane, composed of mechanosensitive apical Ca(2+) channels and a variety of kinases/phosphatases as well as other signaling molecules anchored to the cytoskeleton, and that an increase in tubular fluid flow rate leads to IC- and PC-specific responses determined, in large part, by the cell-specific composition of the BK channels.
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Affiliation(s)
| | - Marcelo D Carattino
- Renal-Electrolyte Division, Department of Medicine, Pittsburgh, Pennsylvania
| | - Thomas R Kleyman
- Renal-Electrolyte Division, Department of Medicine, Pittsburgh, Pennsylvania
| | - Lisa M Satlin
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, New York; and
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12
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Optogenetic control of insulin secretion by pancreatic β-cells in vitro and in vivo. Gene Ther 2015; 22:553-9. [DOI: 10.1038/gt.2015.23] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Revised: 02/12/2015] [Accepted: 02/19/2015] [Indexed: 12/12/2022]
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13
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Mehta S, Zhang J. Dynamic visualization of calcium-dependent signaling in cellular microdomains. Cell Calcium 2015; 58:333-41. [PMID: 25703691 DOI: 10.1016/j.ceca.2015.01.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 01/20/2015] [Accepted: 01/21/2015] [Indexed: 11/17/2022]
Abstract
Cells rely on the coordinated action of diverse signaling molecules to sense, interpret, and respond to their highly dynamic external environment. To ensure the specific and robust flow of information, signaling molecules are often spatially organized to form distinct signaling compartments, and our understanding of the molecular mechanisms that guide intracellular signaling hinges on the ability to directly probe signaling events within these cellular microdomains. Ca(2+) signaling in particular owes much of its functional versatility to this type of exquisite spatial regulation. As discussed below, a number of methods have been developed to investigate the mechanistic and functional implications of microdomains of Ca(2+) signaling, ranging from the application of Ca(2+) buffers to the direct and targeted visualization of Ca(2+) signaling microdomains using genetically encoded fluorescent reporters.
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Affiliation(s)
- Sohum Mehta
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jin Zhang
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; The Solomon H. Snyder Department of Neuroscience, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Oncology, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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14
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Dawn A, Singh S, More KR, Siddiqui FA, Pachikara N, Ramdani G, Langsley G, Chitnis CE. The central role of cAMP in regulating Plasmodium falciparum merozoite invasion of human erythrocytes. PLoS Pathog 2014; 10:e1004520. [PMID: 25522250 PMCID: PMC4270784 DOI: 10.1371/journal.ppat.1004520] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 10/15/2014] [Indexed: 12/19/2022] Open
Abstract
All pathogenesis and death associated with Plasmodium falciparum malaria is due to parasite-infected erythrocytes. Invasion of erythrocytes by P. falciparum merozoites requires specific interactions between host receptors and parasite ligands that are localized in apical organelles called micronemes. Here, we identify cAMP as a key regulator that triggers the timely secretion of microneme proteins enabling receptor-engagement and invasion. We demonstrate that exposure of merozoites to a low K+ environment, typical of blood plasma, activates a bicarbonate-sensitive cytoplasmic adenylyl cyclase to raise cytosolic cAMP levels and activate protein kinase A, which regulates microneme secretion. We also show that cAMP regulates merozoite cytosolic Ca2+ levels via induction of an Epac pathway and demonstrate that increases in both cAMP and Ca2+ are essential to trigger microneme secretion. Our identification of the different elements in cAMP-dependent signaling pathways that regulate microneme secretion during invasion provides novel targets to inhibit blood stage parasite growth and prevent malaria. The blood stage of malaria parasites is responsible for all the morbidity and mortality associated with malaria. During the blood stage, malaria parasites invade and multiply within host erythrocytes. The process of erythrocyte invasion requires specific interactions between host receptors and parasite ligands. Many of the key parasite proteins that bind host receptors are localized in apical organelles called micronemes. Here, we demonstrate that cAMP serves as a key regulator that controls the timely secretion of microneme proteins during invasion. We show that exposure of merozoites to a low K+ environment, as found in blood plasma, leads to a rise in cytosolic cAMP levels due to activation of the cytoplasmic, bicarbonate-sensitive adenylyl cyclase β (PfACβ). A rise in cAMP activates protein kinase A (PKA), which regulates microneme secretion. In addition, cAMP triggers a rise in cytosolic Ca2+ levels through the Epac pathway. Increases in both cAMP and Ca2+ levels are essential for triggering microneme secretion. Identification of the different elements in the cAMP-dependent signaling pathways that regulate microneme secretion during invasion provides novel targets to block erythrocyte invasion, inhibit blood stage parasite growth and prevent malaria.
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Affiliation(s)
- Amrita Dawn
- Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Shailja Singh
- Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
- Malaria Parasite Biology and Vaccines Unit, Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
| | - Kunal R. More
- Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Faiza Amber Siddiqui
- Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Niseema Pachikara
- Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Ghania Ramdani
- Laboratoire de Biologie Cellulaire Comparative des Apicomplexes, Institut Cochin, INSERM U1016, CNRS UMR 8104, Paris, France
| | - Gordon Langsley
- Laboratoire de Biologie Cellulaire Comparative des Apicomplexes, Institut Cochin, INSERM U1016, CNRS UMR 8104, Paris, France
| | - Chetan E. Chitnis
- Malaria Group, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
- Malaria Parasite Biology and Vaccines Unit, Department of Parasites and Insect Vectors, Institut Pasteur, Paris, France
- * E-mail:
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15
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Transient Receptor Potential Vanilloid 4-Induced Modulation of Voltage-Gated Sodium Channels in Hippocampal Neurons. Mol Neurobiol 2014; 53:759-768. [DOI: 10.1007/s12035-014-9038-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Accepted: 11/30/2014] [Indexed: 02/03/2023]
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16
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Averaimo S, Nicol X. Intermingled cAMP, cGMP and calcium spatiotemporal dynamics in developing neuronal circuits. Front Cell Neurosci 2014; 8:376. [PMID: 25431549 PMCID: PMC4230202 DOI: 10.3389/fncel.2014.00376] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 10/21/2014] [Indexed: 01/27/2023] Open
Abstract
cAMP critically modulates the development of neuronal connectivity. It is involved in a wide range of cellular processes that require independent regulation. However, our understanding of how this single second messenger achieves specific modulation of the signaling pathways involved remains incomplete. The subcellular compartmentalization and temporal regulation of cAMP signals have recently been identified as important coding strategies leading to specificity. Dynamic interactions of this cyclic nucleotide with other second messenger including calcium and cGMP are critically involved in the regulation of spatiotemporal control of cAMP. Recent technical improvements of fluorescent sensors facilitate cAMP monitoring, whereas optogenetic tools permit spatial and temporal control of cAMP manipulations, all of which enabled the direct investigation of spatiotemporal characteristics of cAMP modulation in developing neurons. Focusing on neuronal polarization, neurotransmitter specification, axon guidance, and refinement of neuronal connectivity, we summarize herein the recent advances in understanding the features of cAMP signals and their dynamic interactions with calcium and cGMP involved in shaping the nervous system.
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Affiliation(s)
- Stefania Averaimo
- UMR_7210, Centre National de la Recherche Scientifique Paris, France ; UMR_S 968, Institut de la Vision, Sorbonne Universités, UPMC Univ Paris 06 Paris, France ; U968, Institut National de la Santé et de la Recherche Médicale Paris, France
| | - Xavier Nicol
- UMR_7210, Centre National de la Recherche Scientifique Paris, France ; UMR_S 968, Institut de la Vision, Sorbonne Universités, UPMC Univ Paris 06 Paris, France ; U968, Institut National de la Santé et de la Recherche Médicale Paris, France
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17
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Calcium signaling in axon guidance. Trends Neurosci 2014; 37:424-32. [DOI: 10.1016/j.tins.2014.05.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Revised: 05/15/2014] [Accepted: 05/23/2014] [Indexed: 01/22/2023]
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18
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Horng T. Calcium signaling and mitochondrial destabilization in the triggering of the NLRP3 inflammasome. Trends Immunol 2014; 35:253-61. [PMID: 24646829 DOI: 10.1016/j.it.2014.02.007] [Citation(s) in RCA: 205] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 02/16/2014] [Accepted: 02/23/2014] [Indexed: 12/14/2022]
Abstract
The NLRP3 inflammasome is a cytosolic complex that activates Caspase-1, leading to maturation of interleukin-1β (IL-1β) and IL-18 and induction of proinflammatory cell death in sentinel cells of the innate immune system. Diverse stimuli have been shown to activate the NLRP3 inflammasome during infection and metabolic diseases, implicating the pathway in triggering both adaptive and maladaptive inflammation in various clinically important settings. Here I discuss the emerging model that signals associated with mitochondrial destabilization may critically activate the NLRP3 inflammasome. Together with studies indicating an important role for Ca2+ signaling, these findings suggest that many stimuli engage Ca2+ signaling as an intermediate step to trigger mitochondrial destabilization, generating the mitochondrion-associated ligands that activate the NLRP3 inflammasome.
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Affiliation(s)
- Tiffany Horng
- Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston, MA, USA; Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA.
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19
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Sutherland DJ, Goodhill GJ. The interdependent roles of Ca(2+) and cAMP in axon guidance. Dev Neurobiol 2013; 75:402-10. [PMID: 25783999 DOI: 10.1002/dneu.22144] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 10/14/2013] [Accepted: 10/30/2013] [Indexed: 01/21/2023]
Abstract
Axon guidance is a fundamental process in the developing and regenerating nervous system that is necessary for accurate neuronal wiring and proper brain function. Two of the most important second messengers in axon guidance are Ca(2+) and cAMP. Recently experimental and theoretical studies have uncovered a Ca(2+) - and cAMP-dependent mechanism for switching between attraction and repulsion. Here, we review this process and related Ca(2+) and cAMP interactions, the mechanisms by which necessary intracellular calcium elevations are created, and the pathways, which effect attractive and repulsive responses to the switch.
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Affiliation(s)
- Daniel J Sutherland
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
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20
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Tewson PH, Quinn AM, Hughes TE. A multiplexed fluorescent assay for independent second-messenger systems: decoding GPCR activation in living cells. JOURNAL OF BIOMOLECULAR SCREENING 2013; 18:797-806. [PMID: 23580666 PMCID: PMC4242713 DOI: 10.1177/1087057113485427] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
There is a growing need in drug discovery and basic research to measure multiple second-messenger components of cell signaling pathways in real time and in relevant tissues and cell types. Many G-protein-coupled receptors activate the heterotrimeric protein, Gq, which in turn activates phospholipase C (PLC). PLC cleaves phosphatidylinositol 4,5-bisphosphate (PIP2) to produce two second messengers: diacylglycerol (DAG), which remains in the plasma membrane, and inositol triphosphate (IP3), which diffuses through the cytosol to release stores of intracellular calcium ions (Ca(2+)). Our goal was to create a series of multiplex sensors that would make it possible to simultaneously measure two different components of the Gq pathway in living cells. Here we describe new fluorescent sensors for DAG and PIP2 that produce robust changes in green or red fluorescence and can be combined with one another, or with existing Ca(2+) sensors, in a live-cell assay. These assays can detect multiple components of Gq signaling, simultaneously in real time, on standard fluorescent plate readers or live-cell imaging systems.
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21
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Extracellular calcium influx activates adenylate cyclase 1 and potentiates insulin secretion in MIN6 cells. Biochem J 2013; 450:365-73. [PMID: 23282092 DOI: 10.1042/bj20121022] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Intracellular cAMP and Ca(2+) are important second messengers that regulate insulin secretion in pancreatic β-cells; however, the molecular mechanism underlying their mutual interaction for exocytosis is not fully understood. In the present study, we investigated the interplay between intracellular cAMP and Ca(2+) concentrations ([cAMP](i) and [Ca(2+)](i) respectively) in the pancreatic β-cell line MIN6 using total internal reflection fluorescence microscopy. For measuring [cAMP](i), we developed a genetically encoded yellow fluorescent biosensor for cAMP [Flamindo (fluorescent cAMP indicator)], which changes fluorescence intensity with cAMP binding. Application of high-KCl or glucose to MIN6 cells induced the elevation of [cAMP](i) and exocytosis. Furthermore, application of an L-type Ca(2+) channel agonist or ionomycin to induce extracellular Ca(2+) influx evoked the elevation of [cAMP](i), whereas application of carbachol or thapsigargin, which mobilize Ca(2+) from internal stores, did not evoke the elevation of [cAMP](i). We performed RT (reverse transcription)-PCR analysis and found that Ca(2+)-sensitive Adcy1 (adenylate cyclase 1) was expressed in MIN6 cells. Knockdown of endogenous ADCY1 by small interference RNA significantly suppressed glucose-induced exocytosis and the elevation of both [cAMP](i) and [Ca(2+)](i). Taken together, the findings of the present study demonstrate that ADCY1 plays an important role in the control of pancreatic β-cell cAMP homoeostasis and insulin secretion.
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22
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Schwab A, Fabian A, Hanley PJ, Stock C. Role of ion channels and transporters in cell migration. Physiol Rev 2013; 92:1865-913. [PMID: 23073633 DOI: 10.1152/physrev.00018.2011] [Citation(s) in RCA: 315] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cell motility is central to tissue homeostasis in health and disease, and there is hardly any cell in the body that is not motile at a given point in its life cycle. Important physiological processes intimately related to the ability of the respective cells to migrate include embryogenesis, immune defense, angiogenesis, and wound healing. On the other side, migration is associated with life-threatening pathologies such as tumor metastases and atherosclerosis. Research from the last ≈ 15 years revealed that ion channels and transporters are indispensable components of the cellular migration apparatus. After presenting general principles by which transport proteins affect cell migration, we will discuss systematically the role of channels and transporters involved in cell migration.
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23
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Seale AP, Watanabe S, Grau EG. Osmoreception: perspectives on signal transduction and environmental modulation. Gen Comp Endocrinol 2012; 176:354-60. [PMID: 22036842 DOI: 10.1016/j.ygcen.2011.10.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 10/05/2011] [Accepted: 10/12/2011] [Indexed: 01/16/2023]
Abstract
Osmoregulation is essential to life in vertebrates and osmoreception is a fundamental element in osmoregulation. Progress in characterizing the mechanisms that mediate osmoreception has been made possible by using a uniquely accessible cell model, the prolactin (PRL) cell of the euryhaline tilapia, Oreochromis mossambicus. In addition to a brief historical overview, we offer a summary of our recent progress on signal transduction and osmosensitivity in the tilapia PRL cell model. Prolactin is a central regulator of hydromineral balance in teleosts in freshwater (FW). Consistent with its essential role in FW osmoregulation, PRL release in tilapia is inversely related to extracellular osmolality, both in vivo and in vitro. Osmotically-driven changes in PRL cell volume control PRL release. A decrease in extracellular osmolality increases cell volume, leading to a rapid influx of Ca(2+) through stretch-activated channels followed by a sharp rise in PRL release. Our recent studies also suggest that cAMP is involved in the osmotic signal transduction, and that acclimation salinity can modulate PRL cell osmosensitivity. Prolactin cells from FW tilapia show a larger rise in PRL release after a reduction in medium osmolality than those from SW fish. Paradoxically, hyposmotically-induced increase in PRL mRNA was observed only in cells from SW fish. Our studies have revealed differences in the abundance of the water channel, aquaporin 3 (AQP3), and the stretch activated Ca(2+) channel, transient receptor potential vanilloid 4 (TRPV4) in PRL cells of FW and SW fish that may explain their differing osmosensitivity and osmoreceptive output in differing acclimation salinities.
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Affiliation(s)
- A P Seale
- Hawai'i Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, USA.
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24
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de Araújo Leite JC, Marques-Santos LF. Extracellular Ca2+influx is crucial for the early embryonic development of the sea urchinEchinometra lucunter. JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION 2012; 318:123-33. [DOI: 10.1002/jezb.21450] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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25
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Lundgren TK, Nakahata K, Fritz N, Rebellato P, Zhang S, Uhlén P. RET PLCγ phosphotyrosine binding domain regulates Ca2+ signaling and neocortical neuronal migration. PLoS One 2012; 7:e31258. [PMID: 22355350 PMCID: PMC3280273 DOI: 10.1371/journal.pone.0031258] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 01/04/2012] [Indexed: 12/15/2022] Open
Abstract
The receptor tyrosine kinase RET plays an essential role during embryogenesis in regulating cell proliferation, differentiation, and migration. Upon glial cell line-derived neurotrophic factor (GDNF) stimulation, RET can trigger multiple intracellular signaling pathways that in concert activate various downstream effectors. Here we report that the RET receptor induces calcium (Ca2+) signaling and regulates neocortical neuronal progenitor migration through the Phospholipase-C gamma (PLCγ) binding domain Tyr1015. This signaling cascade releases Ca2+ from the endoplasmic reticulum through the inositol 1,4,5-trisphosphate receptor and stimulates phosphorylation of ERK1/2 and CaMKII. A point mutation at Tyr1015 on RET or small interfering RNA gene silencing of PLCγ block the GDNF-induced signaling cascade. Delivery of the RET mutation to neuronal progenitors in the embryonic ventricular zone using in utero electroporation reveal that Tyr1015 is necessary for GDNF-stimulated migration of neurons to the cortical plate. These findings demonstrate a novel RET mediated signaling pathway that elevates cytosolic Ca2+ and modulates neuronal migration in the developing neocortex through the PLCγ binding domain Tyr1015.
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MESH Headings
- Animals
- Apoptosis
- Blotting, Western
- Calcium Signaling/physiology
- Cell Movement
- Cell Proliferation
- Cells, Cultured
- Embryo, Mammalian/cytology
- Embryo, Mammalian/metabolism
- Glial Cell Line-Derived Neurotrophic Factor/genetics
- Glial Cell Line-Derived Neurotrophic Factor/metabolism
- Humans
- Immunoenzyme Techniques
- Inositol 1,4,5-Trisphosphate Receptors/genetics
- Inositol 1,4,5-Trisphosphate Receptors/metabolism
- Mice
- Neocortex/embryology
- Neocortex/metabolism
- Neurons/cytology
- Neurons/metabolism
- Phospholipase C gamma/antagonists & inhibitors
- Phospholipase C gamma/genetics
- Phospholipase C gamma/metabolism
- Phosphorylation
- Phosphotyrosine/metabolism
- Proto-Oncogene Proteins c-ret/genetics
- Proto-Oncogene Proteins c-ret/metabolism
- RNA, Messenger/genetics
- RNA, Small Interfering/genetics
- Real-Time Polymerase Chain Reaction
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Affiliation(s)
- T. Kalle Lundgren
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- Department of Reconstructive Plastic Surgery, Karolinska University Hospital, Stockholm, Sweden
| | - Katsutoshi Nakahata
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Nicolas Fritz
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Paola Rebellato
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Songbai Zhang
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Per Uhlén
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
- * E-mail:
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26
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Cross-talk between calcium and protein kinase A in the regulation of cell migration. Curr Opin Cell Biol 2011; 23:554-61. [PMID: 21665456 DOI: 10.1016/j.ceb.2011.05.006] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 05/16/2011] [Accepted: 05/17/2011] [Indexed: 12/31/2022]
Abstract
Calcium (Ca(2+)) and the cAMP-dependent protein kinase (PKA) are pleiotropic cellular regulators and both exert powerful, diverse effects on cytoskeletal dynamics, cell adhesion, and cell migration. Localization, by A-kinase-anchoring proteins (AKAPs), of PKA activity to the protrusive leading edge, integrins, and other regulators of cytoskeletal dynamics has emerged as an important facet of its role in cell migration. Additional recent work has firmly established the importance of Ca(2+) influx through mechanosensitive transient receptor potential (TRP) channels and through store-operated Ca(2+) entry (SOCE) in cell migration. Finally, there is considerable evidence showing that these mechanisms of Ca(2+) influx and PKA regulation intersect--and often interact--and thus may work in concert to translate complex extracellular cues into the intracellular biochemical anisotropy required for directional cell migration.
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27
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Seale AP, Mita M, Hirano T, Gordon Grau E. Involvement of the cAMP messenger system and extracellular Ca(2+) during hyposmotically-induced prolactin release in the Mozambique tilapia. Gen Comp Endocrinol 2011; 170:401-7. [PMID: 21050855 DOI: 10.1016/j.ygcen.2010.10.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 09/15/2010] [Accepted: 10/23/2010] [Indexed: 11/21/2022]
Abstract
In accord with its role in freshwater osmoregulation, prolactin (PRL) release from the tilapia pituitary is stimulated by small, physiologically relevant reductions in plasma osmolality, a response that is mediated by an acute influx of intracellular Ca(2+) through stretch-activated Ca(2+)channels. In the present study, the role of the calcium and cyclic AMP (cAMP) messenger system in the transduction of a response to a hyposmotic stimulus was examined using dispersed PRL cells and PRL cell membrane preparations from freshwater-acclimated tilapia. When PRL cells were treated with the phosphodiesterase (PDE) inhibitor, 3-isobutyl-1-methylxanthine (IBMX) (100μM), significant increases in cAMP levels and PRL release were observed at 1h. Exposure to reduced medium osmolality (300 mOsmolal) in the presence of IBMX further augmented PRL release. Depletion of Ca(2+) from the incubation medium blocked PRL release even in the presence of IBMX. By contrast, exposure of PRL cells to cholera toxin (CTX), an activator of adenylyl cyclase (AC), stimulated PRL release and cAMP accumulation in both the presence and absence of extracellular Ca(2+). On the other hand, treatment with the Ca(2+) ionophore A23187, which elicits a large rise in intracellular free Ca(2+), reduced cAMP accumulation. Likewise, the AC activity of a PRL cell membrane preparation was reduced as extracellular Ca(2+) concentration increased from 0.1 to 1 μM. These results indicate that: (1) the stimulation of PRL release and cAMP formation by a fall in extracellular osmolality are Ca(2+)-dependent; (2) large increases in intracellular Ca(2+) attenuate cAMP formation; (3) direct agonists of cAMP messenger system, such as cholera toxin, however, stimulate PRL release independently of the extracellular Ca(2+). These findings add to the evidence that the osmosensitive response of the tilapia PRL cell is mediated through a Ca(2+)-dependent mechanism. Nevertheless, the present findings also suggest that tilapia PRL cells have the ability to rapidly augment release PRL both via a Ca(2+)-dependent manner and via a cAMP-dependent pathway in the absence of extracellular Ca(2+).
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Affiliation(s)
- Andre P Seale
- Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, USA
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28
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Ni Q, Ganesan A, Aye-Han NN, Gao X, Allen MD, Levchenko A, Zhang J. Signaling diversity of PKA achieved via a Ca2+-cAMP-PKA oscillatory circuit. Nat Chem Biol 2010; 7:34-40. [PMID: 21102470 PMCID: PMC3073414 DOI: 10.1038/nchembio.478] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Accepted: 09/30/2010] [Indexed: 12/21/2022]
Abstract
Many protein kinases are key nodal signaling molecules that regulate a wide range of cellular functions. These functions may require complex spatiotemporal regulation of kinase activities. Here, we show that protein kinase A (PKA), Ca(2+) and cyclic AMP (cAMP) oscillate in sync in insulin-secreting MIN6 beta cells, forming a highly integrated oscillatory circuit. We found that PKA activity was essential for this oscillatory circuit and was capable of not only initiating the signaling oscillations but also modulating their frequency, thereby diversifying the spatiotemporal control of downstream signaling. Our findings suggest that exquisite temporal control of kinase activity, mediated via signaling circuits resulting from cross-regulation of signaling pathways, can encode diverse inputs into temporal parameters such as oscillation frequency, which in turn contribute to proper regulation of complex cellular functions in a context-dependent manner.
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Affiliation(s)
- Qiang Ni
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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29
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Leykauf K, Treeck M, Gilson PR, Nebl T, Braulke T, Cowman AF, Gilberger TW, Crabb BS. Protein kinase a dependent phosphorylation of apical membrane antigen 1 plays an important role in erythrocyte invasion by the malaria parasite. PLoS Pathog 2010; 6:e1000941. [PMID: 20532217 PMCID: PMC2880582 DOI: 10.1371/journal.ppat.1000941] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 05/05/2010] [Indexed: 11/19/2022] Open
Abstract
Apicomplexan parasites are obligate intracellular parasites that infect a variety of hosts, causing significant diseases in livestock and humans. The invasive forms of the parasites invade their host cells by gliding motility, an active process driven by parasite adhesion proteins and molecular motors. A crucial point during host cell invasion is the formation of a ring-shaped area of intimate contact between the parasite and the host known as a tight junction. As the invasive zoite propels itself into the host-cell, the junction moves down the length of the parasite. This process must be tightly regulated and signalling is likely to play a role in this event. One crucial protein for tight-junction formation is the apical membrane antigen 1 (AMA1). Here we have investigated the phosphorylation status of this key player in the invasion process in the human malaria parasite Plasmodium falciparum. We show that the cytoplasmic tail of P. falciparum AMA1 is phosphorylated at serine 610. We provide evidence that the enzyme responsible for serine 610 phosphorylation is the cAMP regulated protein kinase A (PfPKA). Importantly, mutation of AMA1 serine 610 to alanine abrogates phosphorylation of AMA1 in vivo and dramatically impedes invasion. In addition to shedding unexpected new light on AMA1 function, this work represents the first time PKA has been implicated in merozoite invasion.
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Affiliation(s)
- Kerstin Leykauf
- Macfarlane Burnet Institute for Medical Research & Public Health, Melbourne, Victoria, Australia
| | - Moritz Treeck
- Bernhard Nocht Institute for Tropical Medicine, Department of Molecular Parasitology, Hamburg, Germany
| | - Paul R. Gilson
- Macfarlane Burnet Institute for Medical Research & Public Health, Melbourne, Victoria, Australia
| | - Thomas Nebl
- Walter & Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
| | - Thomas Braulke
- Department of Biochemistry, Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Alan F. Cowman
- Walter & Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia
| | - Tim W. Gilberger
- Bernhard Nocht Institute for Tropical Medicine, Department of Molecular Parasitology, Hamburg, Germany
- M.G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada
| | - Brendan S. Crabb
- Macfarlane Burnet Institute for Medical Research & Public Health, Melbourne, Victoria, Australia
- The University of Melbourne, Victoria, Australia
- Monash University, Victoria, Australia
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30
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Lewis BB, Wester MR, Miller LE, Nagarkar MD, Johnson MB, Saha MS. Cloning and characterization of voltage-gated calcium channel alpha1 subunits in Xenopus laevis during development. Dev Dyn 2010; 238:2891-902. [PMID: 19795515 DOI: 10.1002/dvdy.22102] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Voltage-gated calcium channels play a critical role in regulating the Ca2+ activity that mediates many aspects of neural development, including neural induction, neurotransmitter phenotype specification, and neurite outgrowth. Using Xenopus laevis embryos, we describe the spatial and temporal expression patterns during development of the 10 pore-forming alpha1 subunits that define the channels' kinetic properties. In situ hybridization indicates that CaV1.2, CaV2.1, CaV2.2, and CaV3.2 are expressed during neurula stages throughout the neural tube. These, along with CaV1.3 and CaV2.3, beginning at early tail bud stages, and CaV3.1 at late tail bud stages, are detected in complex patterns within the brain and spinal cord through swimming tadpole stages. Additional expression of various alpha1 subunits was observed in the cranial ganglia, retina, olfactory epithelium, pineal gland, and heart. The unique expression patterns for the different alpha1 subunits suggests they are under precise spatial and temporal regulation and are serving specific functions during embryonic development.
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Affiliation(s)
- Brittany B Lewis
- Department of Biology, The College of William and Mary, Integrated Science Center, Williamsburg, Virginia 23185, USA
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Dunn TA, Storm DR, Feller MB. Calcium-dependent increases in protein kinase-A activity in mouse retinal ganglion cells are mediated by multiple adenylate cyclases. PLoS One 2009; 4:e7877. [PMID: 19924297 PMCID: PMC2774513 DOI: 10.1371/journal.pone.0007877] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2009] [Accepted: 10/26/2009] [Indexed: 11/28/2022] Open
Abstract
Neurons undergo long term, activity dependent changes that are mediated by activation of second messenger cascades. In particular, calcium-dependent activation of the cyclic-AMP/Protein kinase A signaling cascade has been implicated in several developmental processes including cell survival, axonal outgrowth, and axonal refinement. The biochemical link between calcium influx and the activation of the cAMP/PKA pathway is primarily mediated through adenylate cyclases. Here, dual imaging of intracellular calcium concentration and PKA activity was used to assay the role of different classes of calcium-dependent adenylate cyclases (ACs) in the activation of the cAMP/PKA pathway in retinal ganglion cells (RGCs). Surprisingly, depolarization-induced calcium-dependent PKA transients persist in barrelless mice lacking AC1, the predominant calcium-dependent adenylate cyclase in RGCs, as well as in double knockout mice lacking both AC1 and AC8. Furthermore, in a subset of RGCs, depolarization-induced PKA transients persist during the inhibition of all transmembrane adenylate cyclases. These results are consistent with the existence of a soluble adenylate cyclase that plays a role in calcium-dependent activation of the cAMP/PKA cascade in neurons.
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Affiliation(s)
- Timothy A. Dunn
- Neurobiology Section, Division of Biological Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Daniel R. Storm
- Department of Pharmacology, University of Washington, Seattle, Washington, United States of America
| | - Marla B. Feller
- Department of Molecular and Cell Biology and the Helen Wills Neuroscience Institute, University of California, Berkeley, California, United States of America
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Mironov SL, Skorova E, Taschenberger G, Hartelt N, Nikolaev VO, Lohse MJ, Kügler S. Imaging cytoplasmic cAMP in mouse brainstem neurons. BMC Neurosci 2009; 10:29. [PMID: 19327133 PMCID: PMC2674597 DOI: 10.1186/1471-2202-10-29] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2008] [Accepted: 03/27/2009] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND cAMP is an ubiquitous second messenger mediating various neuronal functions, often as a consequence of increased intracellular Ca2+ levels. While imaging of calcium is commonly used in neuroscience applications, probing for cAMP levels has not yet been performed in living vertebrate neuronal tissue before. RESULTS Using a strictly neuron-restricted promoter we virally transduced neurons in the organotypic brainstem slices which contained pre-Bötzinger complex, constituting the rhythm-generating part of the respiratory network. Fluorescent cAMP sensor Epac1-camps was expressed both in neuronal cell bodies and neurites, allowing us to measure intracellular distribution of cAMP, its absolute levels and time-dependent changes in response to physiological stimuli. We recorded [cAMP]i changes in the micromolar range after modulation of adenylate cyclase, inhibition of phosphodiesterase and activation of G-protein-coupled metabotropic receptors. [cAMP]i levels increased after membrane depolarisation and release of Ca2+ from internal stores. The effects developed slowly and reached their maximum after transient [Ca2+]i elevations subsided. Ca2+-dependent [cAMP]i transients were suppressed after blockade of adenylate cyclase with 0.1 mM adenylate cyclase inhibitor 2'5'-dideoxyadenosine and potentiated after inhibiting phosphodiesterase with isobutylmethylxanthine and rolipram. During paired stimulations, the second depolarisation and Ca2+ release evoked bigger cAMP responses. These effects were abolished after inhibition of protein kinase A with H-89 pointing to the important role of phosphorylation of calcium channels in the potentiation of [cAMP]i transients. CONCLUSION We constructed and characterized a neuron-specific cAMP probe based on Epac1-camps. Using viral gene transfer we showed its efficient expression in organotypic brainstem preparations. Strong fluorescence, resistance to photobleaching and possibility of direct estimation of [cAMP] levels using dual wavelength measurements make the probe useful in studies of neurons and the mechanisms of their plasticity. Epac1-camps was applied to examine the crosstalk between Ca2+ and cAMP signalling and revealed a synergism of actions of these two second messengers.
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Affiliation(s)
- SL Mironov
- DFG-Center of Molecular Physiology of the Brain, Department of Neuro- and Sensory Physiology, Humboldtallee 23, Georg-August-University, 37073 Göttingen, Germany
| | - E Skorova
- DFG-Center of Molecular Physiology of the Brain, Department of Neuro- and Sensory Physiology, Humboldtallee 23, Georg-August-University, 37073 Göttingen, Germany
| | - G Taschenberger
- University Medical Center Göttingen, Department of Neurology, Waldweg 33, 37073 Göttingen, Germany
| | - N Hartelt
- DFG-Center of Molecular Physiology of the Brain, Department of Neuro- and Sensory Physiology, Humboldtallee 23, Georg-August-University, 37073 Göttingen, Germany
| | - VO Nikolaev
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, 97078 Würzburg, Germany
| | - MJ Lohse
- Institute of Pharmacology and Toxicology, University of Würzburg, Versbacher Str. 9, 97078 Würzburg, Germany
| | - S Kügler
- University Medical Center Göttingen, Department of Neurology, Waldweg 33, 37073 Göttingen, Germany
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Merckx A, Bouyer G, Thomas SLY, Langsley G, Egée S. Anion channels in Plasmodium-falciparum-infected erythrocytes and protein kinase A. Trends Parasitol 2009; 25:139-44. [PMID: 19200784 DOI: 10.1016/j.pt.2008.12.005] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 12/01/2008] [Accepted: 12/10/2008] [Indexed: 01/09/2023]
Abstract
By replicating within red blood cells, malaria parasites are largely hidden from immune recognition; however, in the cells, nutrients are limiting and hazardous metabolic end products can rapidly accumulate. Therefore, to survive within erythrocytes, parasites alter the permeability of the host plasma membrane, either by upregulating existing transporters or by creating new permeation pathways. Recent electrophysiological studies of Plasmodium-infected erythrocytes have demonstrated that membrane permeability is mediated by transmembrane transport through ion channels in the infected erythrocyte. This article discusses the evidence and controversies concerning the nature of these channels and surveys the potential role of phosphorylation in activating anion channels that could be important in developing novel strategies for future malarial chemotherapies.
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Affiliation(s)
- Anaïs Merckx
- Institut Cochin, INSERM U567, Université Paris Descartes, CNRS (UMR 8104), Paris, France
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Martín‐Belmonte F, Rodríguez‐Fraticelli AE. Chapter 3 Acquisition of Membrane Polarity in Epithelial Tube Formation. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2009; 274:129-82. [DOI: 10.1016/s1937-6448(08)02003-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Tengholm A, Idevall-Hagren O. Spatio-temporal dynamics of phosphatidylinositol-3,4,5-trisphosphate signalling. VITAMINS AND HORMONES 2009; 80:287-311. [PMID: 19251042 DOI: 10.1016/s0083-6729(08)00611-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Many effects of insulin, insulin-like growth factors and other receptor stimuli are mediated via the phospholipid second messenger phosphatidylinositol-3,4,5-trisphosphate (PIP(3)). PIP(3) is formed by the activity of phosphoinositide 3-kinases in the plasma membrane, where it serves to recruit signalling proteins. These proteins coordinate complex events leading to changes in cell metabolism, growth, movement and survival. Over the past decade, new techniques for measurements of PIP(3) in the plasma membrane of individual living cells have markedly improved our understanding of the role of this messenger in a variety of cellular processes. This review summarises the mechanisms involved in formation and degradation of PIP(3) in insulin-responsive cells, how PIP(3) can be measured in individual cells as well as accumulating evidence that the plasma membrane PIP(3) concentration undergoes complex spatio-temporal patterns in many types of cells, with particular emphasis on autocrine insulin-induced PIP(3) oscillations in pancreatic beta-cells.
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Affiliation(s)
- Anders Tengholm
- Department of Medical Cell Biology, Uppsala University, Biomedical Centre, Uppsala, Sweden
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36
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Abstract
A characteristic feature of developing neural circuits is that they are spontaneously active. There are several examples, including the retina, spinal cord, and hippocampus, where spontaneous activity is highly correlated among neighboring cells, with large depolarizing events occurring with a periodicity on the order of minutes. One likely mechanism by which neurons can "decode" these slow oscillations is through activation of second messenger cascades that either influence transcriptional activity or drive posttranslational modifications. Here, we describe recent experiments where imaging has been used to characterize slow oscillations in the cAMP/PKA second messenger cascade in retinal neurons. We review the latest techniques in imaging this specific second messenger cascade, its intimate relationship with changes in intracellular calcium concentration, and several hypotheses regarding its role in neurodevelopment.
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Affiliation(s)
- Timothy A Dunn
- Division of Biological Sciences, University of California at San Diego, La Jolla, California, USA
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Ono T, Cabrita-Santos L, Leitao R, Bettiol E, Purcell LA, Diaz-Pulido O, Andrews LB, Tadakuma T, Bhanot P, Mota MM, Rodriguez A. Adenylyl cyclase alpha and cAMP signaling mediate Plasmodium sporozoite apical regulated exocytosis and hepatocyte infection. PLoS Pathog 2008; 4:e1000008. [PMID: 18389080 PMCID: PMC2279260 DOI: 10.1371/journal.ppat.1000008] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Accepted: 01/22/2008] [Indexed: 11/19/2022] Open
Abstract
Malaria starts with the infection of the liver of the host by Plasmodium sporozoites, the parasite form transmitted by infected mosquitoes. Sporozoites migrate through several hepatocytes by breaching their plasma membranes before finally infecting one with the formation of an internalization vacuole. Migration through host cells induces apical regulated exocytosis in sporozoites. Here we show that apical regulated exocytosis is induced by increases in cAMP in sporozoites of rodent (P. yoelii and P. berghei) and human (P. falciparum) Plasmodium species. We have generated P. berghei parasites deficient in adenylyl cyclase alpha (ACalpha), a gene containing regions with high homology to adenylyl cyclases. PbACalpha-deficient sporozoites do not exocytose in response to migration through host cells and present more than 50% impaired hepatocyte infectivity in vivo. These effects are specific to ACalpha, as re-introduction of ACalpha in deficient parasites resulted in complete recovery of exocytosis and infection. Our findings indicate that ACalpha and increases in cAMP levels are required for sporozoite apical regulated exocytosis, which is involved in sporozoite infection of hepatocytes.
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Affiliation(s)
- Takeshi Ono
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Laura Cabrita-Santos
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Ricardo Leitao
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Esther Bettiol
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Lisa A. Purcell
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | - Olga Diaz-Pulido
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
| | | | - Takushi Tadakuma
- Department of Parasitology and Immunology, National Defense Medical College, Tokorozawa, Saitama, Japan
| | - Purnima Bhanot
- Department of Microbiology and Molecular Genetics, New Jersey Medical School, Newark, New Jersey, United States of America
| | - Maria M. Mota
- Faculdade de Medicina da Universidade de Lisboa, Instituto de Medicina Molecular, Lisboa, Portugal
| | - Ana Rodriguez
- Department of Medical Parasitology, New York University School of Medicine, New York, New York, United States of America
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