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Garcia-Casas P, Rossini M, Filadi R, Pizzo P. Mitochondrial Ca 2+ signaling and Alzheimer's disease: Too much or too little? Cell Calcium 2023; 113:102757. [PMID: 37192560 DOI: 10.1016/j.ceca.2023.102757] [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: 02/28/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/18/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease, caused by poorly known pathogenic mechanisms and aggravated by delayed therapeutic intervention, that still lacks an effective cure. However, it is clear that some important neurophysiological processes are altered years before the onset of clinical symptoms, offering the possibility of identifying biological targets useful for implementation of new therapies. Of note, evidence has been provided suggesting that mitochondria, pivotal organelles in sustaining neuronal energy demand and modulating synaptic activity, are dysfunctional in AD samples. In particular, alterations in mitochondrial Ca2+ signaling have been proposed as causal events for neurodegeneration, although the exact outcomes and molecular mechanisms of these defects, as well as their longitudinal progression, are not always clear. Here, we discuss the importance of a correct mitochondrial Ca2+ handling for neuronal physiology and summarize the latest findings on dysfunctional mitochondrial Ca2+ pathways in AD, analysing possible consequences contributing to the neurodegeneration that characterizes the disease.
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Affiliation(s)
- Paloma Garcia-Casas
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy; Department of Biochemistry and Molecular Biology and Physiology, School of Medicine, University of Valladolid, 47003 Valladolid, Spain
| | - Michela Rossini
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy
| | - Riccardo Filadi
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy; Neuroscience Institute, National Research Council (CNR), 35131 Padua, Italy.
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy; Neuroscience Institute, National Research Council (CNR), 35131 Padua, Italy; Study Centre for Neurodegeneration (CESNE), University of Padova, 35131 Padua, Italy.
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2
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Therapeutic Strategies to Target Calcium Dysregulation in Alzheimer's Disease. Cells 2020; 9:cells9112513. [PMID: 33233678 PMCID: PMC7699688 DOI: 10.3390/cells9112513] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 11/17/2020] [Accepted: 11/18/2020] [Indexed: 12/31/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common form of dementia, affecting millions of people worldwide. Unfortunately, none of the current treatments are effective at improving cognitive function in AD patients and, therefore, there is an urgent need for the development of new therapies that target the early cause(s) of AD. Intracellular calcium (Ca2+) regulation is critical for proper cellular and neuronal function. It has been suggested that Ca2+ dyshomeostasis is an upstream factor of many neurodegenerative diseases, including AD. For this reason, chemical agents or small molecules aimed at targeting or correcting this Ca2+ dysregulation might serve as therapeutic strategies to prevent the development of AD. Moreover, neurons are not alone in exhibiting Ca2+ dyshomeostasis, since Ca2+ disruption is observed in other cell types in the brain in AD. In this review, we examine the distinct Ca2+ channels and compartments involved in the disease mechanisms that could be potential targets in AD.
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3
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Calvo-Rodriguez M, Bacskai BJ. Mitochondria and Calcium in Alzheimer's Disease: From Cell Signaling to Neuronal Cell Death. Trends Neurosci 2020; 44:136-151. [PMID: 33160650 DOI: 10.1016/j.tins.2020.10.004] [Citation(s) in RCA: 123] [Impact Index Per Article: 30.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 09/03/2020] [Accepted: 10/07/2020] [Indexed: 02/06/2023]
Abstract
Mitochondrial dysfunction has been implicated in the pathogenesis of almost all neurological diseases, including Alzheimer's disease (AD). Historically, a primary focus in this context has been the link between mitochondrial dynamics and amyloid β toxicity. Recent evidence suggests that dysregulation of mitochondrial calcium homeostasis is also related to tau and other risk factors in AD, although an ongoing challenge in the field is that data collected from different models or experimental settings have not always been consistent. We examine recent literature on mitochondrial dysregulation in AD, with special emphasis on mitochondrial calcium. We include data from in vitro systems, genetic animal models, and AD-derived human tissue, and discuss whether mitochondrial calcium transporters should be proposed as therapeutic candidates for the development of neuroprotective drugs against AD.
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Affiliation(s)
- Maria Calvo-Rodriguez
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114 16th Street, Charlestown, MA 02129, USA
| | - Brian J Bacskai
- Alzheimer Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 114 16th Street, Charlestown, MA 02129, USA.
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4
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Galla L, Redolfi N, Pozzan T, Pizzo P, Greotti E. Intracellular Calcium Dysregulation by the Alzheimer's Disease-Linked Protein Presenilin 2. Int J Mol Sci 2020; 21:E770. [PMID: 31991578 PMCID: PMC7037278 DOI: 10.3390/ijms21030770] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 01/17/2020] [Accepted: 01/21/2020] [Indexed: 12/18/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia. Even though most AD cases are sporadic, a small percentage is familial due to autosomal dominant mutations in amyloid precursor protein (APP), presenilin-1 (PSEN1), and presenilin-2 (PSEN2) genes. AD mutations contribute to the generation of toxic amyloid β (Aβ) peptides and the formation of cerebral plaques, leading to the formulation of the amyloid cascade hypothesis for AD pathogenesis. Many drugs have been developed to inhibit this pathway but all these approaches currently failed, raising the need to find additional pathogenic mechanisms. Alterations in cellular calcium (Ca2+) signaling have also been reported as causative of neurodegeneration. Interestingly, Aβ peptides, mutated presenilin-1 (PS1), and presenilin-2 (PS2) variously lead to modifications in Ca2+ homeostasis. In this contribution, we focus on PS2, summarizing how AD-linked PS2 mutants alter multiple Ca2+ pathways and the functional consequences of this Ca2+ dysregulation in AD pathogenesis.
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Affiliation(s)
- Luisa Galla
- Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy; (L.G.); (N.R.); (T.P.); (E.G.)
- Neuroscience Institute, National Research Council (CNR), 35131 Padua, Italy
| | - Nelly Redolfi
- Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy; (L.G.); (N.R.); (T.P.); (E.G.)
| | - Tullio Pozzan
- Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy; (L.G.); (N.R.); (T.P.); (E.G.)
- Neuroscience Institute, National Research Council (CNR), 35131 Padua, Italy
- Venetian Institute of Molecular Medicine (VIMM), 35131 Padua, Italy
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy; (L.G.); (N.R.); (T.P.); (E.G.)
- Neuroscience Institute, National Research Council (CNR), 35131 Padua, Italy
| | - Elisa Greotti
- Department of Biomedical Sciences, University of Padua, 35131 Padua, Italy; (L.G.); (N.R.); (T.P.); (E.G.)
- Neuroscience Institute, National Research Council (CNR), 35131 Padua, Italy
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5
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High-Throughput Fluorescence Assays for Ion Channels and GPCRs. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:27-72. [DOI: 10.1007/978-3-030-12457-1_3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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6
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Sushma, Mondal AC. Role of GPCR signaling and calcium dysregulation in Alzheimer's disease. Mol Cell Neurosci 2019; 101:103414. [PMID: 31655116 DOI: 10.1016/j.mcn.2019.103414] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 09/17/2019] [Accepted: 09/24/2019] [Indexed: 12/12/2022] Open
Abstract
Alzheimer's disease (AD), a late onset neurodegenerative disorder is characterized by the loss of memory, disordered cognitive function, caused by accumulation of amyloid-β (Aβ) peptide and neurofibrillary tangles (NFTs) in the neocortex and hippocampal brain area. Extensive research has been done on the findings of the disease etiology or pathological causes of aggregation of Aβ and hyperphosphorylation of tau protein without much promising results. Recently, calcium dysregulation has been reported to play an important role in the pathophysiology of AD. Calcium ion acts as one of the major secondary messengers, regulates many signaling pathways involved in cell survival, proliferation, differentiation, transcription and apoptosis. Calcium signaling is one of the major signaling pathways involved in the formation of memory, generation of energy and other physiological functions. It also can modulate function of many proteins upon binding. Dysregulation in calcium homeostasis leads to many physiological changes leading to neurodegenerative diseases including AD. In AD, GPCRs generate secondary messengers which regulate calcium homeostasis inside the cell and is reported to be disturbed in the pathological condition. Calcium channels and receptors present on the plasma membrane and intracellular organelle maintain calcium homeostasis through different signaling mechanisms. In this review, we have summarized the different calcium channels and receptors involved in calcium dysregulation which in turn play a critical role in the pathogenesis of AD. Understanding the role of calcium channels and GPCRs to maintain calcium homeostasis is an attempt to develop effective AD treatments.
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Affiliation(s)
- Sushma
- Laboratory of Cellular and Molecular Neurobiology, School of Life Sciences, Jawaharlal Nehru University, New Delhi, Delhi, India
| | - Amal Chandra Mondal
- Laboratory of Cellular and Molecular Neurobiology, School of Life Sciences, Jawaharlal Nehru University, New Delhi, Delhi, India.
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7
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Okubo Y. [Neuronal cell death induced by the disruption of endoplasmic reticulum-mediated Ca 2+ signaling]. Nihon Yakurigaku Zasshi 2019; 153:155-160. [PMID: 30971654 DOI: 10.1254/fpj.153.155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
For the function and survival of neurons in the central nervous system, it is indispensable that the intracellular Ca2+ dynamics are properly controlled. The endoplasmic reticulum (ER), a major intracellular Ca2+ store, plays an important role in the control of the intracellular Ca2+ dynamics in neurons through the supply and uptake of Ca2+. It has been suggested that the disruption of ER Ca2+ signaling is involved in neuronal cell death in various pathological conditions. Therefore, the disruption of ER Ca2+ signaling has attracted attention as a novel mechanism for neurodegenerative diseases including Alzheimer's disease. In this review, we introduce the latest findings including our research on the relationship between the disruption of ER Ca2+ signaling and neuronal cell death. In addition, we will introduce recent developments on the technology for visualizing intraluminal Ca2+ dynamics within the ER, which is indispensable for promoting research in this field.
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Affiliation(s)
- Yohei Okubo
- Department of Pharmacology, Graduate School of Medicine, The University of Tokyo
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8
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Wang X, Zheng W. Ca 2+ homeostasis dysregulation in Alzheimer's disease: a focus on plasma membrane and cell organelles. FASEB J 2019; 33:6697-6712. [PMID: 30848934 DOI: 10.1096/fj.201801751r] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Emerging evidence indicates that Ca2+ is a vital factor in modulating the pathogenesis of Alzheimer's disease (AD). In healthy neurons, Ca2+ concentration is balanced to maintain a lower level in the cytosol than in the extracellular space or certain intracellular compartments such as endoplasmic reticulum (ER) and the lysosome, whereas this homeostasis is broken in AD. On the plasma membrane, the AD hallmarks amyloid-β (Aβ) and tau interact with ligand-gated or voltage-gated Ca2+-influx channels and inhibit the Ca2+-efflux ATPase or exchangers, leading to an elevated intracellular Ca2+ level and disrupted Ca2+ signal. In the ER, the disabled presenilin "Ca2+ leak" function and the direct implications of Aβ and presenilin mutants contribute to Ca2+-signal disorder. The enhanced ryanodine receptor (RyR)-mediated and inositol 1,4,5-trisphosphate receptor (IP3R)-mediated Ca2+ release from the ER aggravates cytosolic Ca2+ disorder and triggers apoptosis; the down-regulated ER Ca2+ sensor, stromal interaction molecule (STIM), alleviates store-operated Ca2+ entry in plasma membrane, leading to spine loss. The increased transfer of Ca2+ from ER to mitochondria through mitochondria-associated ER membrane (MAM) causes Ca2+ overload in the mitochondrial matrix and consequently opens the cellular damage-related channel, mitochondrial permeability transition pore (mPTP). In this review, we discuss the effects of Aβ, tau and presenilin on neuronal Ca2+ signal, focusing on the receptors and regulators in plasma membrane and ER; we briefly introduce the involvement of MAM-mediated Ca2+ transfer and mPTP opening in AD pathogenesis.-Wang, X., Zheng, W. Ca2+ homeostasis dysregulation in Alzheimer's disease: a focus on plasma membrane and cell organelles.
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Affiliation(s)
- Xingjian Wang
- Department of Histology and Embryology, College of Basic Medical Science, China Medical University, Shenyang, China
| | - Wei Zheng
- Department of Histology and Embryology, College of Basic Medical Science, China Medical University, Shenyang, China
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9
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Familial Alzheimer's disease-linked presenilin mutants and intracellular Ca 2+ handling: A single-organelle, FRET-based analysis. Cell Calcium 2019; 79:44-56. [PMID: 30822648 DOI: 10.1016/j.ceca.2019.02.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 01/29/2019] [Accepted: 02/11/2019] [Indexed: 10/27/2022]
Abstract
An imbalance in Ca2+ homeostasis represents an early event in the pathogenesis of Alzheimer's disease (AD). Presenilin-1 and -2 (PS1 and PS2) mutations, the major cause of familial AD (FAD), have been extensively associated with alterations in different Ca2+ signaling pathways, in particular those handled by storage compartments. However, FAD-PSs effect on organelles Ca2+ content is still debated and the mechanism of action of mutant proteins is unclear. To fulfil the need of a direct investigation of intracellular stores Ca2+ dynamics, we here present a detailed and quantitative single-cell analysis of FAD-PSs effects on organelle Ca2+ handling using specifically targeted, FRET (Fluorescence/Förster Resonance Energy Transfer)-based Ca2+ indicators. In SH-SY5Y human neuroblastoma cells and in patient-derived fibroblasts expressing different FAD-PSs mutations, we directly measured Ca2+ concentration within the main intracellular Ca2+ stores, e.g., Endoplasmic Reticulum (ER) and Golgi Apparatus (GA) medial- and trans-compartment. We unambiguously demonstrate that the expression of FAD-PS2 mutants, but not FAD-PS1, in either SH-SY5Y cells or FAD patient-derived fibroblasts, is able to alter Ca2+ handling of ER and medial-GA, but not trans-GA, reducing, compared to control cells, the Ca2+ content within these organelles by partially blocking SERCA (Sarco/Endoplasmic Reticulum Ca2+-ATPase) activity. Moreover, by using a cytosolic Ca2+ probe, we show that the expression of both FAD-PS1 and -PS2 reduces the Ca2+ influx activated by stores depletion (Store-Operated Ca2+ Entry; SOCE), by decreasing the expression levels of one of the key molecules, STIM1 (STromal Interaction Molecule 1), controlling this pathway. Our data indicate that FAD-linked PSs mutants differentially modulate the Ca2+ content of intracellular stores yet leading to a complex dysregulation of Ca2+ homeostasis, which represents a common disease phenotype of AD.
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10
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Okubo Y, Mikami Y, Kanemaru K, Iino M. Role of Endoplasmic Reticulum-Mediated Ca 2+ Signaling in Neuronal Cell Death. Antioxid Redox Signal 2018; 29:1147-1157. [PMID: 29361832 DOI: 10.1089/ars.2018.7498] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
SIGNIFICANCE Properly controlled intracellular Ca2+ dynamics is crucial for regulation of neuronal function and survival in the central nervous system. The endoplasmic reticulum (ER), a major intracellular Ca2+ store, plays a critical role as a source and sink for neuronal Ca2+. Recent Advances: Accumulating evidence indicates that disrupted ER Ca2+ signaling is involved in neuronal cell death under various pathological conditions, providing novel insight into neurodegenerative disease mechanisms. CRITICAL ISSUES We summarize current knowledge concerning the relationship between abnormal ER Ca2+ dynamics and neuronal cell death. We also introduce recent technical advances for probing ER intraluminal Ca2+ dynamics with unprecedented spatiotemporal resolution. FUTURE DIRECTIONS Further studies on ER Ca2+ signaling are expected to provide progress for unmet medical needs in neurodegenerative disease. Antioxid. Redox Signal. 29, 1147-1157.
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Affiliation(s)
- Yohei Okubo
- 1 Department of Pharmacology, Graduate School of Medicine, The University of Tokyo , Tokyo, Japan
| | - Yoshinori Mikami
- 2 Department of Physiology, School of Medicine, Faculty of Medicine, Toho University , Tokyo, Japan
| | - Kazunori Kanemaru
- 1 Department of Pharmacology, Graduate School of Medicine, The University of Tokyo , Tokyo, Japan .,3 Department of Cellular and Molecular Pharmacology, Nihon University School of Medicine , Tokyo, Japan
| | - Masamitsu Iino
- 3 Department of Cellular and Molecular Pharmacology, Nihon University School of Medicine , Tokyo, Japan
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11
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Tong BCK, Wu AJ, Li M, Cheung KH. Calcium signaling in Alzheimer's disease & therapies. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:1745-1760. [PMID: 30059692 DOI: 10.1016/j.bbamcr.2018.07.018] [Citation(s) in RCA: 126] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 07/12/2018] [Accepted: 07/23/2018] [Indexed: 12/15/2022]
Abstract
Alzheimer's disease (AD) is the most common type of dementia and is characterized by the accumulation of amyloid (Aβ) plaques and neurofibrillary tangles in the brain. Much attention has been given to develop AD treatments based on the amyloid cascade hypothesis; however, none of these drugs had good efficacy at improving cognitive functions in AD patients suggesting that Aβ might not be the disease origin. Thus, there are urgent needs for the development of new therapies that target on the proximal cause of AD. Cellular calcium (Ca2+) signals regulate important facets of neuronal physiology. An increasing body of evidence suggests that age-related dysregulation of neuronal Ca2+ homeostasis may play a proximal role in the pathogenesis of AD as disrupted Ca2+ could induce synaptic deficits and promote the accumulation of Aβ plaques and neurofibrillary tangles. Given that Ca2+ disruption is ubiquitously involved in all AD pathologies, it is likely that using chemical agents or small molecules specific to Ca2+ channels or handling proteins on the plasma membrane and membranes of intracellular organelles to correct neuronal Ca2+ dysregulation could open up a new approach to AD prevention and treatment. This review summarizes current knowledge on the molecular mechanisms linking Ca2+ dysregulation with AD pathologies and discusses the possibility of correcting neuronal Ca2+ disruption as a therapeutic approach for AD.
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Affiliation(s)
- Benjamin Chun-Kit Tong
- School of Chinese Medicine, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, China
| | - Aston Jiaxi Wu
- School of Chinese Medicine, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, China
| | - Min Li
- School of Chinese Medicine, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, China
| | - King-Ho Cheung
- School of Chinese Medicine, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong, China.
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12
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Gazda K, Kuznicki J, Wegierski T. Knockdown of amyloid precursor protein increases calcium levels in the endoplasmic reticulum. Sci Rep 2017; 7:14512. [PMID: 29109429 PMCID: PMC5673940 DOI: 10.1038/s41598-017-15166-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 10/23/2017] [Indexed: 12/15/2022] Open
Abstract
Familial Alzheimer's disease (AD) is caused by mutations in the genes that encode amyloid precursor protein (APP) and presenilins. Disturbances in calcium homeostasis have been observed in various cellular and animal models of AD and are proposed to underlie the pathogenesis of the disease. Furthermore, wildtype presenilins were shown to regulate endoplasmic reticulum (ER) calcium homeostasis, although their precise mechanism of action remains controversial. To investigate whether APP also affects ER calcium levels, we used RNA interference to target the APP gene in cultured T84 cells in combination with two types of ER calcium sensors. Using a genetically encoded calcium indicator, GEM-CEPIA1er, we found that APP-deficient cells exhibited elevated resting calcium levels in the ER and prolonged emptying of ER calcium stores upon the cyclopiazonic acid-induced inhibition of sarco-endoplasmic reticulum calcium-ATPase. These effects could be ascribed to lower ER calcium leakage rates. Consistent with these results, translocation of the endogenous ER calcium sensor STIM1 to its target channel Orai1 was delayed following ER calcium store depletion. Our data suggest a physiological function of APP in the regulation of ER calcium levels.
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Affiliation(s)
- Kinga Gazda
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, 02-109, Warsaw, Poland
| | - Jacek Kuznicki
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, 02-109, Warsaw, Poland
| | - Tomasz Wegierski
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, 02-109, Warsaw, Poland.
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Toussay X, Morel JL, Biendon N, Rotureau L, Legeron FP, Boutonnet MC, Cho YH, Macrez N. Presenilin 1 mutation decreases both calcium and contractile responses in cerebral arteries. Neurobiol Aging 2017; 58:201-212. [PMID: 28753475 DOI: 10.1016/j.neurobiolaging.2017.06.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 06/09/2017] [Accepted: 06/19/2017] [Indexed: 12/26/2022]
Abstract
Mutations or upregulation in presenilin 1 (PS1) gene are found in familial early-onset Alzheimer's disease or sporadic late-onset Alzheimer's disease, respectively. PS1 has been essentially studied in neurons and its mutation was shown to alter intracellular calcium (Ca2+) signals. Here, we showed that PS1 is expressed in smooth muscle cells (SMCs) of mouse cerebral arteries, and we assessed the effects of the deletion of exon 9 of PS1 (PS1dE9) on Ca2+ signals and contractile responses of vascular SMC. Agonist-induced contraction of cerebral vessels was significantly decreased in PS1dE9 both in vivo and ex vivo. Spontaneous activity of Ca2+ sparks through ryanodine-sensitive channels (RyR) was unchanged, whereas the RyR-mediated Ca2+-release activated by caffeine was shorter in PS1dE9 SMC when compared with control. Moreover, PS1dE9 mutation decreased the caffeine-activated capacitive Ca2+ entry, and inhibitors of SERCA pumps reversed the effects of PS1dE9 on Ca2+ signals. PS1dE9 mutation also leads to the increased expression of SERCA3, phospholamban, and RyR3. These results show that PS1 plays a crucial role in the cerebrovascular system and the vascular reactivity is decreased through altered Ca2+ signals in PS1dE9 mutant mice.
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Affiliation(s)
- Xavier Toussay
- University Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Centre de Neurosciences Intégratives et Cognitives, UMR 5228, Bordeaux, France
| | - Jean-Luc Morel
- University Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
| | - Nathalie Biendon
- University Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
| | - Lolita Rotureau
- University Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Centre de Neurosciences Intégratives et Cognitives, UMR 5228, Bordeaux, France
| | - François-Pierre Legeron
- University Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
| | - Marie-Charlotte Boutonnet
- University Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France
| | - Yoon H Cho
- CNRS, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, UMR 5287, Bordeaux, France
| | - Nathalie Macrez
- University Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, Bordeaux, France.
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14
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Tong BCK, Lee CSK, Cheng WH, Lai KO, Foskett JK, Cheung KH. Familial Alzheimer's disease-associated presenilin 1 mutants promote γ-secretase cleavage of STIM1 to impair store-operated Ca2+ entry. Sci Signal 2016; 9:ra89. [PMID: 27601731 DOI: 10.1126/scisignal.aaf1371] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Some forms of familial Alzheimer's disease (FAD) are caused by mutations in presenilins (PSs), catalytic components of a γ-secretase complex that cleaves target proteins, including amyloid precursor protein (APP). Calcium (Ca(2+)) dysregulation in cells with these FAD-causing PS mutants has been attributed to attenuated store-operated Ca(2+) entry [SOCE; also called capacitative Ca(2+) entry (CCE)]. CCE occurs when STIM1 detects decreases in Ca(2+) in the endoplasmic reticulum (ER) and activates ORAI channels to replenish Ca(2+) stores in the ER. We showed that CCE was attenuated by PS1-associated γ-secretase activity. Endogenous PS1 and STIM1 interacted in human neuroblastoma SH-SY5Y cells, patient fibroblasts, and mouse primary cortical neurons. Forms of PS1 with FAD-associated mutations enhanced γ-secretase cleavage of the STIM1 transmembrane domain at a sequence that was similar to the γ-secretase cleavage sequence of APP. Cultured hippocampal neurons expressing mutant PS1 had attenuated CCE that was associated with destabilized dendritic spines, which were rescued by either γ-secretase inhibition or overexpression of STIM1. Our results indicate that γ-secretase activity may physiologically regulate CCE by targeting STIM1 and that restoring STIM1 may be a therapeutic approach in AD.
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Affiliation(s)
- Benjamin Chun-Kit Tong
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| | - Claire Shuk-Kwan Lee
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| | - Wing-Hei Cheng
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| | - Kwok-On Lai
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China. State Key Laboratory of Brain and Cognitive Sciences, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China
| | - J Kevin Foskett
- Departments of Physiology and Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - King-Ho Cheung
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China. State Key Laboratory of Brain and Cognitive Sciences, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China. HKU-Shenzhen Institute of Research and Innovation, Shenzhen, Guangdong, China.
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15
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Walter J. Twenty Years of Presenilins--Important Proteins in Health and Disease. Mol Med 2015; 21 Suppl 1:S41-8. [PMID: 26605647 DOI: 10.2119/molmed.2015.00163] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 07/01/2015] [Indexed: 01/01/2023] Open
Abstract
Alzheimer's disease (AD) is characterized by progressive decline in cognitive functions associated with depositions of aggregated proteins in the form of extracellular plaques and neurofibrillary tangles in the brain. Extracellular plaques contain characteristic fibrils of amyloid β peptides (Aβ); tangles consist of paired helical filaments of the microtubuli-associated protein tau. Although AD manifests predominantly at ages above 65 years, rare cases show a much earlier onset of disease symptoms with very similar neuropathological characteristics. In 1995, two homologous genes were identified, in which mutations are associated with dominantly inherited familial forms of early onset AD. The genes therefore were dubbed presenilins (PS) and encode polytopic transmembrane proteins. At this time the role of these proteins in the pathogenesis of AD and their biological function in general were completely unknown. However, individuals carrying PS mutations showed alterations in the composition of different length variants of Aβ peptides in blood and cerebrospinal fluid, which indicated the potential involvement of presenilins in the metabolism of Aβ. After 20 years of intense research, the roles of presenilins in Aβ generation as well as important functions in biological processes have been identified. Presenilins represent the catalytic components of protease complexes that directly cleave the amyloid precursor protein (APP) but also many other proteins with important physiological functions. Here, the progress in presenilin research from basic characterization of their cellular functions to the targeting in clinical trials for AD therapy, and potential future directions, will be discussed.
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Affiliation(s)
- Jochen Walter
- Department of Neurology, University of Bonn, Bonn, Germany
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16
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Park JG, Palmer AE. Properties and use of genetically encoded FRET sensors for cytosolic and organellar Ca2+ measurements. Cold Spring Harb Protoc 2015; 2015:pdb.top066043. [PMID: 25561625 DOI: 10.1101/pdb.top066043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In the last 15 years, there has been an explosion in the development of genetically encoded biosensors that report enzyme activity, chemical transformation, or concentration of ions and molecules in living cells. Currently, there are well over 120 biosensors of different cellular targets. As a general design principle, these sensors convert a molecular event, such as the binding of a molecule to a sensing domain or a signal-induced change in protein conformation, into a change in the sensor's fluorescence properties. In contrast to small-molecule sensors, genetically encoded sensors are generated when sensor-encoding nucleic acid sequences, which have been introduced by transgenic technologies, are translated in cells, tissues, or organisms. One of the best developed classes of biosensors is the genetically encoded Ca(2+) indicators (GECIs). Here, we briefly summarize the properties of ratiometric GECIs and describe how they are used to quantify Ca(2+) in specific cellular locations, such as the cytosol, nucleus, endoplasmic reticulum, and mitochondria.
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Affiliation(s)
- J Genevieve Park
- Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, Colorado 80309
| | - Amy E Palmer
- Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, Colorado 80309
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Park JG, Palmer AE. Verifying the function and localization of genetically encoded Ca2+ sensors and converting FRET ratios to Ca2+ concentrations. Cold Spring Harb Protoc 2015; 2015:pdb.prot076547. [PMID: 25561614 DOI: 10.1101/pdb.prot076547] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Genetically encoded, ratiometric, fluorescent Ca(2+) biosensors can be used in living cells to quantitatively measure free Ca(2+) concentrations in the cytosol or in organelles. This protocol describes how to perform a calibration of a Ca(2+) sensor expressed in cultured mammalian cells as images are acquired using a widefield fluorescence microscope. This protocol also explains how to calculate Förster resonance energy transfer (FRET) ratios from acquired images and how to convert FRET ratios to Ca(2+) concentrations.
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Affiliation(s)
- J Genevieve Park
- Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, Colorado 80309
| | - Amy E Palmer
- Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, Colorado 80309
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18
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Abstract
The signal peptide peptidase (SPP)-related intramembrane aspartyl proteases are a homologous group of polytopic membrane proteins, some of which function in innate or adaptive immunity by cleaving proteins involved in antigen presentation or intracellular signaling. Signal peptide peptidase-like 3 (SPPL3) is a poorly characterized endoplasmic reticulum (ER)-localized member of this family, with no validated cellular substrates. We report here the isolation of SPPL3 in a screen for activators of NFAT, a transcription factor that controls lymphocyte development and function. We find that SPPL3 is required downstream of T cell receptor engagement for maximal Ca(2+) influx and NFAT activation. Surprisingly, the proteolytic activity of SPPL3 is not required for its role in this pathway. SPPL3 enhances the signal-induced association of stromal interaction molecule 1 (STIM1) and Orai1 and is even required for the full activity of constitutively active STIM1 variants that bind Orai1 independently of ER Ca(2+) release. SPPL3 associates with STIM1 through at least two independent domains, the transmembrane region and the CRAC activation domain (CAD), and can promote the association of the STIM1 CAD with Orai1. Our results assign a function in lymphocyte signaling to SPPL3 and highlight the emerging importance of nonproteolytic functions for members of the intramembrane aspartyl protease family.
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Evensen NA, Kuscu C, Nguyen HL, Zarrabi K, Dufour A, Kadam P, Hu YJ, Pulkoski-Gross A, Bahou WF, Zucker S, Cao J. Unraveling the role of KIAA1199, a novel endoplasmic reticulum protein, in cancer cell migration. J Natl Cancer Inst 2013; 105:1402-16. [PMID: 23990668 DOI: 10.1093/jnci/djt224] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Cell migration is a critical determinant of cancer metastasis, and a better understanding of the genes involved will lead to the identification of novel targets aimed at preventing cancer dissemination. KIAA1199 has been shown to be upregulated in human cancers, yet its role in cancer progression was hitherto unknown. METHODS Clinical relevance was assessed by examining KIAA1199 expression in human cancer specimens. In vitro and in vivo studies were employed to determine the function of KIAA1199 in cancer progression. Cellular localization of KIAA1199 was microscopically determined. SNAP-tag pull-down assays were used to identify binding partner(s) of KIAA1199. Calcium levels were evaluated using spectrofluorometric and fluorescence resonance energy transfer analyses. Signaling pathways were dissected by Western blotting. Student t test was used to assess differences. All statistical tests were two-sided. RESULTS KIAA1199 was upregulated in invasive breast cancer specimens and inversely associated with patient survival rate. Silencing of KIAA1199 in MDA-MB-435 cancer cells resulted in a mesenchymal-to-epithelial transition that reduced cell migratory ability in vitro (75% reduction; P < .001) and decreased metastasis in vivo (80% reduction; P < .001). Gain-of-function assays further demonstrated the role of KIAA1199 in cell migration. KIAA1199-enhanced cell migration required endoplasmic reticulum (ER) localization, where it forms a stable complex with the chaperone binding immunoglobulin protein (BiP). A novel ER-retention motif within KIAA1199 that is required for its ER localization, BiP interaction, and enhanced cell migration was identified. Mechanistically, KIAA1199 was found to mediate ER calcium leakage, and the resultant increase in cytosolic calcium ultimately led to protein kinase C alpha activation and cell migration. CONCLUSIONS KIAA1199 serves as a novel cell migration-promoting gene and plays a critical role in maintaining cancer mesenchymal status.
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Affiliation(s)
- Nikki A Evensen
- Affiliations of authors: Department of Medicine/Cancer Prevention (NAE, CK, H-LN, KZ, AD, AP-G, JC), Department of Pathology (YH, JC), Department of Medicine/Hematology & Oncology (WFB, SZ), Stony Brook University, Stony Brook, NY; Department of Research, Veterans Affair Medical Center, Northport, NY (H-LN, PK, SZ); Centre for Blood Research and Departments of Biochemistry and Molecular Biology and Oral Biological and Medical Sciences, University of British Columbia, Vancouver, BC, Canada (AD)
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Honarnejad K, Jung CKE, Lammich S, Arzberger T, Kretzschmar H, Herms J. Involvement of presenilin holoprotein upregulation in calcium dyshomeostasis of Alzheimer's disease. J Cell Mol Med 2013; 17:293-302. [PMID: 23379308 PMCID: PMC3822592 DOI: 10.1111/jcmm.12008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Accepted: 11/29/2012] [Indexed: 12/16/2022] Open
Abstract
Mutations in presenilins (PS1 and PS2) account for the vast majority of early onset familial Alzheimer's disease cases. Beside the well investigated role of presenilins as the catalytic unit in γ-secretase complex, their involvement in regulation of intracellular calcium homeostasis has recently come into more focus of Alzheimer's disease research. Here we report that the overexpression of PS1 full-length holoprotein forms, in particular familial Alzheimer's disease-causing forms of PS1, result in significantly attenuated calcium release from thapsigargin- and bradykinin-sensitive stores. Interestingly, treatment of HEK293 cells with γ-secretase inhibitors also leads to decreased amount of calcium release from endoplasmic reticulum (ER) accompanying elevated PS1 holoprotein levels. Similarly, the knockdown of PEN-2 which is associated with deficient PS1 endoproteolysis and accumulation of its holoprotein form also leads to decreased ER calcium release. Notably, we detected enhanced PS1 holoprotein levels also in postmortem brains of patients carrying familial Alzheimer's disease PS1 mutations. Taken together, the conditions in which the amount of full length PS1 holoprotein is increased result in reduction of calcium release from ER. Based on these results, we propose that the disturbed ER calcium homeostasis mediated by the elevation of PS1 holoprotein levels may be a contributing factor to the pathogenesis of Alzheimer's disease.
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Affiliation(s)
- Kamran Honarnejad
- Department of Translational Brain Research, DZNE - German Center for Neurodegenerative Diseases, Munich, Germany
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21
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Honarnejad K, Herms J. Presenilins: Role in calcium homeostasis. Int J Biochem Cell Biol 2012; 44:1983-6. [DOI: 10.1016/j.biocel.2012.07.019] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 07/16/2012] [Accepted: 07/18/2012] [Indexed: 01/30/2023]
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22
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Kipanyula MJ, Contreras L, Zampese E, Lazzari C, Wong AKC, Pizzo P, Fasolato C, Pozzan T. Ca2+ dysregulation in neurons from transgenic mice expressing mutant presenilin 2. Aging Cell 2012; 11:885-93. [PMID: 22805202 DOI: 10.1111/j.1474-9726.2012.00858.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Mutations in amyloid precursor protein (APP), and presenilin-1 and presenilin-2 (PS1 and PS2) have causally been implicated in Familial Alzheimer's Disease (FAD), but the mechanistic link between the mutations and the early onset of neurodegeneration is still debated. Although no consensus has yet been reached, most data suggest that both FAD-linked PS mutants and endogenous PSs are involved in cellular Ca2+ homeostasis. We here investigated subcellular Ca2+ handling in primary neuronal cultures and acute brain slices from wild type and transgenic mice carrying the FAD-linked PS2-N141I mutation, either alone or in the presence of the APP Swedish mutation. Compared with wild type, both types of transgenic neurons show a similar reduction in endoplasmic reticulum (ER) Ca2+ content and decreased response to metabotropic agonists, albeit increased Ca2+ release induced by caffeine. In both transgenic neurons, we also observed a higher ER-mitochondria juxtaposition that favors increased mitochondrial Ca2+ uptake upon ER Ca2+ release. A model is described that integrates into a unifying hypothesis the contradictory effects on Ca2+ homeostasis of different PS mutations and points to the relevance of these findings in neurodegeneration and aging.
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23
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Mbatia HW, Burdette SC. Photochemical Tools for Studying Metal Ion Signaling and Homeostasis. Biochemistry 2012; 51:7212-24. [DOI: 10.1021/bi3001769] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Hannah W. Mbatia
- University of Connecticut, 55 North Eagleville
Road, Storrs, Connecticut 06269-3060, United
States
| | - Shawn C. Burdette
- Worcester Polytechnic Institute, 100 Institute Road, Worcester, Massachusetts
01609-2280, United States
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24
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Shilling D, Foskett JK. Reply to Bezprozvanny et al.: Response to Shilling et al. (10.1074/jbc.M111.300491). J Biol Chem 2012. [DOI: 10.1074/jbc.l112.371450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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25
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McMullen DC, Kean WS, Verma A, Cole JT, Watson WD. A microplate technique to simultaneously assay calcium accumulation in endoplasmic reticulum and SERCA release of inorganic phosphate. Biol Proced Online 2012; 14:4. [PMID: 22472432 PMCID: PMC3388579 DOI: 10.1186/1480-9222-14-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 04/02/2012] [Indexed: 01/02/2023] Open
Abstract
Traditional analyses of calcium homeostasis have separately quantified either calcium accumulation or release mechanisms. To define the system as a whole, however, requires multiple experimental techniques to examine both accumulation and release. Here we describe a technique that couples the simultaneous quantification of radio-labeled calcium accumulation in endoplasmic reticulum (ER) microsomes with the release of inorganic phosphate (Pi) by the hydrolytic activity of sarco-endoplasmic reticulum calcium ATPase (SERCA) all in the convenience of a 96-well format.
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Affiliation(s)
- David C McMullen
- Department of Neurology, Uniformed Services University of the Health Sciences, B-3059, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
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26
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Shilling D, Mak DOD, Kang DE, Foskett JK. Lack of evidence for presenilins as endoplasmic reticulum Ca2+ leak channels. J Biol Chem 2012; 287:10933-44. [PMID: 22311977 DOI: 10.1074/jbc.m111.300491] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Familial Alzheimer disease (FAD) is linked to mutations in the presenilin (PS) homologs. FAD mutant PS expression has several cellular consequences, including exaggerated intracellular Ca(2+) ([Ca(2+)](i)) signaling due to enhanced agonist sensitivity and increased magnitude of [Ca(2+)](i) signals. The mechanisms underlying these phenomena remain controversial. It has been proposed that PSs are constitutively active, passive endoplasmic reticulum (ER) Ca(2+) leak channels and that FAD PS mutations disrupt this function resulting in ER store overfilling that increases the driving force for release upon ER Ca(2+) release channel opening. To investigate this hypothesis, we employed multiple Ca(2+) imaging protocols and indicators to directly measure ER Ca(2+) dynamics in several cell systems. However, we did not observe consistent evidence that PSs act as ER Ca(2+) leak channels. Nevertheless, we confirmed observations made using indirect measurements employed in previous reports that proposed this hypothesis. Specifically, cells lacking PS or expressing a FAD-linked PS mutation displayed increased area under the ionomycin-induced [Ca(2+)](i) versus time curve (AI) compared with cells expressing WT PS. However, an ER-targeted Ca(2+) indicator revealed that this did not reflect overloaded ER stores. Monensin pretreatment selectively attenuated the AI in cells lacking PS or expressing a FAD PS allele. These findings contradict the hypothesis that PSs form ER Ca(2+) leak channels and highlight the need to use ER-targeted Ca(2+) indicators when studying ER Ca(2+) dynamics.
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Affiliation(s)
- Dustin Shilling
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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27
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Fluorescent Genetically Encoded Calcium Indicators and Their In Vivo Application. FLUORESCENT PROTEINS II 2011. [DOI: 10.1007/4243_2011_29] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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