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Calcium Binding Proteins

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

Deadline for manuscript submissions: closed (31 October 2018) | Viewed by 74386

Special Issue Editor


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Guest Editor
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
Interests: calcium-binding protein; calcium signaling; protein-protein interaction; post-transcriptional regulation; protein structure; membrane traffic
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Special Issue Information

Dear Colleagues,

Calcium ions play pivotal roles in a variety of cellular events including signal transductions, gene expression, cell death, fertilization, muscle contraction, membrane fusion, blood clotting, enzymatic activations of kinases, phosphatases, proteases, etc., by involving different kinds of calcium binding proteins. Concentrations of Ca2+ in the blood and inside the cells are strictly regulated by Ca2+-sensor proteins, -channels, -transporters and -buffering proteins. In addition to the sarcoplasmic/endoplasmic reticulum known as the major Ca2+-storage organelle in the cell, mitochondria, Golgi apparatus, endosomes and lysosomes are also known to play roles in Ca2+-signaling. Nuclear roles of Ca2+ also draw attentions for transcriptional and post-transcriptional regulations. Ca2+ works not only as a second messenger but also works as a first messenger to Ca2+-sensing receptors located on the plasma membrane. Abnormalities in Ca2+ homeostasis or in functions of Ca2+-regulated factors cause directly or indirectly various diseases, such as neuropathy, heart failure, immune disorder, and osteogenesis imperfecta. Ca2+-dependent phenomena are not restricted to animals, but plants, lower eukaryotes and some bacteria also use Ca2+ as a signaling molecule. Calcium ions play structural roles for micelle formation of casein proteins in milk. This Special Issue on “Calcium Binding Proteins” welcomes contributions in all areas of basic and application-oriented research associated with calcium from the aspects of biochemistry, molecular biology and biophysics.

Prof. Dr. Masatoshi Maki
Guest Editor

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Keywords

  • EF-hand proteins
  • Annexin family
  • C2 domain proteins
  • Ion channels and transporters
  • Ca2+ sensor and buffering proteins
  • Ca2+-dependent enzymes
  • Transcription factors
  • Signal transductions
  • Cell growth, differentiation and death
  • Membrane trafficking
  • Organellar Ca2+
  • Ca2+ assay methods

Published Papers (14 papers)

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12 pages, 2805 KiB  
Article
Calretinin Functions in Malignant Mesothelioma Cells Cannot Be Replaced by the Closely Related Ca2+-Binding Proteins Calbindin-D28k and Parvalbumin
by Janine Wörthmüller, Anne Oberson, Valérie Salicio, Walter Blum and Beat Schwaller
Int. J. Mol. Sci. 2018, 19(12), 4015; https://doi.org/10.3390/ijms19124015 - 12 Dec 2018
Cited by 4 | Viewed by 3544
Abstract
Calretinin (CR; CALB2) belonging to the family of EF-hand Ca2+-binding proteins (CaBP) is widely used as a positive marker for the identification of human malignant mesothelioma (MM) and functionally was suggested to play a critical role during carcinogenesis of this [...] Read more.
Calretinin (CR; CALB2) belonging to the family of EF-hand Ca2+-binding proteins (CaBP) is widely used as a positive marker for the identification of human malignant mesothelioma (MM) and functionally was suggested to play a critical role during carcinogenesis of this highly aggressive asbestos-associated neoplasm. Increasing evidence suggests that CR not only acts as a prototypical Ca2+ buffer protein, i.e., limiting the amplitude of Ca2+ signals but also as a Ca2+ sensor. No studies have yet investigated whether other closely related CaBPs might serve as substitutes for CR’s functions(s) in MM cells. Genetically modified MM cell lines with medium (MSTO-211H and ZL5) or low (SPC111) endogenous CR expression levels were generated that overexpress either CR’s closest homologue calbindin-D28k (CB) or parvalbumin (PV), the latter considered as a “pure” Ca2+ buffer protein. After lentiviral shCALB2-mediated CR downregulation, in both MSTO-211H and ZL5 cells expressing CB or PV, the CR deficiency-mediated increase in cell death was not prevented by CB or PV. With respect to proliferation and cell morphology of SPC111 cells, CB was able to substitute for CR, but not for CR’s other functions to promote cell migration or invasion. In conclusion, CR has a likely unique role in MM that cannot be substituted by “similar” CaBPs. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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15 pages, 4315 KiB  
Article
Thermodynamic Characterization of the Ca2+-Dependent Interaction Between SOUL and ALG-2
by Taisuke Mikasa, Masami Kugo, Seigo Nishimura, Sigeru Taketani, Sumio Ishijima and Ikuko Sagami
Int. J. Mol. Sci. 2018, 19(12), 3802; https://doi.org/10.3390/ijms19123802 - 29 Nov 2018
Cited by 6 | Viewed by 3002
Abstract
SOUL, a heme-binding protein-2 (HEBP-2), interacts with apoptosis-linked gene 2 protein (ALG-2) in a Ca2+-dependent manner. To investigate the properties of the interaction of SOUL with ALG-2, we generated several mutants of SOUL and ALG-2 and analyzed the recombinant proteins using [...] Read more.
SOUL, a heme-binding protein-2 (HEBP-2), interacts with apoptosis-linked gene 2 protein (ALG-2) in a Ca2+-dependent manner. To investigate the properties of the interaction of SOUL with ALG-2, we generated several mutants of SOUL and ALG-2 and analyzed the recombinant proteins using pulldown assay and isothermal titration calorimetry. The interaction between SOUL and ALG-2 (delta3-23ALG-2) was an exothermic reaction, with 1:1 stoichiometry and high affinity (Kd = 32.4 nM) in the presence of Ca2+. The heat capacity change (ΔCp) of the reaction showed a large negative value (−390 cal/K·mol), which suggested the burial of a significant nonpolar surface area or disruption of a hydrogen bond network that was induced by the interaction (or both). One-point mutation of SOUL Phe100 or ALG-2 Trp57 resulted in complete loss of heat change, supporting the essential roles of these residues for the interaction. Nevertheless, a truncated mutant of SOUL1-143 that deleted the domain required for the interaction with ALG-2 Trp57 still showed 1:1 binding to ALG-2 with an endothermic reaction. These results provide a better understanding of the target recognition mechanism and conformational change of SOUL in the interaction with ALG-2. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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16 pages, 3463 KiB  
Article
The Effect of Ca2+, Lobe-Specificity, and CaMKII on CaM Binding to NaV1.1
by Jianing Li, Zhiyi Yu, Jianjun Xu, Rui Feng, Qinghua Gao, Tomasz Boczek, Junyan Liu, Zhi Li, Qianhui Wang, Ming Lei, Jian Gong, Huiyuan Hu, Etsuko Minobe, Hong-Long Ji, Masaki Kameyama and Feng Guo
Int. J. Mol. Sci. 2018, 19(9), 2495; https://doi.org/10.3390/ijms19092495 - 23 Aug 2018
Cited by 6 | Viewed by 3341
Abstract
Calmodulin (CaM) is well known as an activator of calcium/calmodulin-dependent protein kinase II (CaMKII). Voltage-gated sodium channels (VGSCs) are basic signaling molecules in excitable cells and are crucial molecular targets for nervous system agents. However, the way in which Ca2+/CaM/CaMKII cascade [...] Read more.
Calmodulin (CaM) is well known as an activator of calcium/calmodulin-dependent protein kinase II (CaMKII). Voltage-gated sodium channels (VGSCs) are basic signaling molecules in excitable cells and are crucial molecular targets for nervous system agents. However, the way in which Ca2+/CaM/CaMKII cascade modulates NaV1.1 IQ (isoleucine and glutamine) domain of VGSCs remains obscure. In this study, the binding of CaM, its mutants at calcium binding sites (CaM12, CaM34, and CaM1234), and truncated proteins (N-lobe and C-lobe) to NaV1.1 IQ domain were detected by pull-down assay. Our data showed that the binding of Ca2+/CaM to the NaV1.1 IQ was concentration-dependent. ApoCaM (Ca2+-free form of calmodulin) bound to NaV1.1 IQ domain preferentially more than Ca2+/CaM. Additionally, the C-lobe of CaM was the predominant domain involved in apoCaM binding to NaV1.1 IQ domain. By contrast, the N-lobe of CaM was predominant in the binding of Ca2+/CaM to NaV1.1 IQ domain. Moreover, CaMKII-mediated phosphorylation increased the binding of Ca2+/CaM to NaV1.1 IQ domain due to one or several phosphorylation sites in T1909, S1918, and T1934 of NaV1.1 IQ domain. This study provides novel mechanisms for the modulation of NaV1.1 by the Ca2+/CaM/CaMKII axis. For the first time, we uncover the effect of Ca2+, lobe-specificity and CaMKII on CaM binding to NaV1.1. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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13 pages, 3103 KiB  
Article
Calcium-Binding Proteins S100A8 and S100A9: Investigation of Their Immune Regulatory Effect in Myeloid Cells
by Jianxin Yang, Jacqueline Anholts, Ulrike Kolbe, Janine A. Stegehuis-Kamp, Frans H. J. Claas and Michael Eikmans
Int. J. Mol. Sci. 2018, 19(7), 1833; https://doi.org/10.3390/ijms19071833 - 21 Jun 2018
Cited by 32 | Viewed by 5860
Abstract
High expression levels of the calcium-binding proteins S100A8 and S100A9 in myeloid cells in kidney transplant rejections are associated with a favorable outcome. Here we investigated the myeloid cell subset expressing these molecules, and their function in inflammatory reactions. Different monocyte subsets were [...] Read more.
High expression levels of the calcium-binding proteins S100A8 and S100A9 in myeloid cells in kidney transplant rejections are associated with a favorable outcome. Here we investigated the myeloid cell subset expressing these molecules, and their function in inflammatory reactions. Different monocyte subsets were sorted from buffy coats of healthy donors and investigated for S100A8 and S100A9 expression. To characterize S100A9high and S100A9low subsets within the CD14+ classical monocyte subset, intracellular S100A9 staining was combined with flow cytometry (FACS) and qPCR profiling. Furthermore, S100A8 and S100A9 were overexpressed by transfection in primary monocyte-derived macrophages and the THP-1 macrophage cell line to investigate the functional relevance. Expression of S100A8 and S100A9 was primarily found in classical monocytes and to a much lower extent in intermediate and non-classical monocytes. All S100A9+ cells expressed human leukocyte antigen—antigen D related (HLA-DR) on their surface. A small population (<3%) of CD14+ CD11b+ CD33+ HLA-DR− cells, characterized as myeloid derived suppressor cells (MDSCs), also expressed S100A9 to high extent. Overexpression of S100A8 and S00A9 in macrophages led to enhanced extracellular reactive oxygen species (ROS) production, as well as elevated mRNA expression of anti-inflammatory IL-10. The results suggest that the calcium-binding proteins S100A8 and S100A9 in myeloid cells have an immune regulatory effect. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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20 pages, 5317 KiB  
Article
Interplay between ER Ca2+ Binding Proteins, STIM1 and STIM2, Is Required for Store-Operated Ca2+ Entry
by Heather A. Nelson, Colin A. Leech, Richard F. Kopp and Michael W. Roe
Int. J. Mol. Sci. 2018, 19(5), 1522; https://doi.org/10.3390/ijms19051522 - 19 May 2018
Cited by 12 | Viewed by 5420
Abstract
Store-operated calcium entry (SOCE), a fundamentally important homeostatic and Ca2+ signaling pathway in many types of cells, is activated by the direct interaction of stromal interaction molecule 1 (STIM1), an endoplasmic reticulum (ER) Ca2+-binding protein, with Ca2+-selective Orai1 [...] Read more.
Store-operated calcium entry (SOCE), a fundamentally important homeostatic and Ca2+ signaling pathway in many types of cells, is activated by the direct interaction of stromal interaction molecule 1 (STIM1), an endoplasmic reticulum (ER) Ca2+-binding protein, with Ca2+-selective Orai1 channels localized in the plasma membrane. While much is known about the regulation of SOCE by STIM1, the role of stromal interaction molecule 2 (STIM2) in SOCE remains incompletely understood. Here, using clustered regularly interspaced short palindromic repeats -CRISPR associated protein 9 (CRISPR-Cas9) genomic editing and molecular imaging, we investigated the function of STIM2 in NIH 3T3 fibroblast and αT3 cell SOCE. We found that deletion of Stim2 expression reduced SOCE by more than 90% in NIH 3T3 cells. STIM1 expression levels were unaffected in the Stim2 null cells. However, quantitative confocal fluorescence imaging demonstrated that in the absence of Stim2 expression, STIM1 did not translocate or form punctae in plasma membrane-associated ER membrane (PAM) junctions following ER Ca2+ store depletion. Fluorescence resonance energy transfer (FRET) imaging of intact, living cells revealed that the formation of STIM1 and Orai1 complexes in PAM nanodomains was significantly reduced in the Stim2 knockout cells. Our findings indicate that STIM2 plays an essential role in regulating SOCE in NIH 3T3 and αT3 cells and suggests that dynamic interplay between STIM1 and STIM2 induced by ER Ca2+ store discharge is necessary for STIM1 translocation, its interaction with Orai1, and activation of SOCE. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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14 pages, 1716 KiB  
Article
GDF11 Modulates Ca2+-Dependent Smad2/3 Signaling to Prevent Cardiomyocyte Hypertrophy
by Javier Duran, Mayarling Francisca Troncoso, Daniel Lagos, Sebastian Ramos, Gabriel Marin and Manuel Estrada
Int. J. Mol. Sci. 2018, 19(5), 1508; https://doi.org/10.3390/ijms19051508 - 18 May 2018
Cited by 23 | Viewed by 5139
Abstract
Growth differentiation factor 11 (GDF11), a member of the transforming growth factor-β family, has been shown to act as a negative regulator in cardiac hypertrophy. Ca2+ signaling modulates cardiomyocyte growth; however, the role of Ca2+-dependent mechanisms in mediating the effects [...] Read more.
Growth differentiation factor 11 (GDF11), a member of the transforming growth factor-β family, has been shown to act as a negative regulator in cardiac hypertrophy. Ca2+ signaling modulates cardiomyocyte growth; however, the role of Ca2+-dependent mechanisms in mediating the effects of GDF11 remains elusive. Here, we found that GDF11 induced intracellular Ca2+ increases in neonatal rat cardiomyocytes and that this response was blocked by chelating the intracellular Ca2+ with BAPTA-AM or by pretreatment with inhibitors of the inositol 1,4,5-trisphosphate (IP3) pathway. Moreover, GDF11 increased the phosphorylation levels and luciferase activity of Smad2/3 in a concentration-dependent manner, and the inhibition of IP3-dependent Ca2+ release abolished GDF11-induced Smad2/3 activity. To assess whether GDF11 exerted antihypertrophic effects by modulating Ca2+ signaling, cardiomyocytes were exposed to hypertrophic agents (100 nM testosterone or 50 μM phenylephrine) for 24 h. Both treatments increased cardiomyocyte size and [3H]-leucine incorporation, and these responses were significantly blunted by pretreatment with GDF11 over 24 h. Moreover, downregulation of Smad2 and Smad3 with siRNA was accompanied by inhibition of the antihypertrophic effects of GDF11. These results suggest that GDF11 modulates Ca2+ signaling and the Smad2/3 pathway to prevent cardiomyocyte hypertrophy. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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17 pages, 11576 KiB  
Article
Calsenilin, a Presenilin Interactor, Regulates RhoA Signaling and Neurite Outgrowth
by Hee-Jun Kim, Won-Haeng Lee, Mo-Jong Kim, Sunmee Shin, Byungki Jang, Jae-Bong Park, Wilma Wasco, Joseph D. Buxbaum, Yong-Sun Kim and Eun-Kyoung Choi
Int. J. Mol. Sci. 2018, 19(4), 1196; https://doi.org/10.3390/ijms19041196 - 13 Apr 2018
Cited by 4 | Viewed by 4815
Abstract
Calsenilin modulates A-type potassium channels, regulates presenilin-mediated γ-secretase activity, and represses prodynorphin and c-fos genes expression. RhoA is involved in various cellular functions including proliferation, differentiation, migration, transcription, and regulation of the actin cytoskeleton. Although recent studies demonstrate that calsenilin can directly interact [...] Read more.
Calsenilin modulates A-type potassium channels, regulates presenilin-mediated γ-secretase activity, and represses prodynorphin and c-fos genes expression. RhoA is involved in various cellular functions including proliferation, differentiation, migration, transcription, and regulation of the actin cytoskeleton. Although recent studies demonstrate that calsenilin can directly interact with RhoA and that RhoA inactivation is essential for neuritogenesis, it is uncertain whether there is a link between calsenilin and RhoA-regulated neuritogenesis. Here, we investigated the role of calsenilin in RhoA-regulated neuritogenesis using in vitro and in vivo systems. We found that calsenilin induced RhoA inactivation, which accompanied RhoA phosphorylation and the reduced phosphorylation levels of LIM kinase (LIMK) and cofilin. Interestingly, PC12 cells overexpressing either full-length (FL) or the caspase 3-derived C-terminal fragment (CTF) of calsenilin significantly inactivated RhoA through its interaction with RhoA and p190 Rho GTPase-activating protein (p190RhoGAP). In addition, cells expressing FL and the CTF of calsenilin had increased neurite outgrowth compared to cells expressing the N-terminal fragment (NTF) of calsenilin or vector alone. Moreover, Tat-C3 and Y27632 treatment significantly increased the percentage of neurite-bearing cells, neurite length, and the number of neurites in cells. Finally, calsenilin deficiency in the brains of calsenilin-knockout mice significantly interfered with RhoA inactivation. These findings suggest that calsenilin contributes to neuritogenesis through RhoA inactivation. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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19 pages, 2639 KiB  
Article
Nanoluciferase Reporter Gene System Directed by Tandemly Repeated Pseudo-Palindromic NFAT-Response Elements Facilitates Analysis of Biological Endpoint Effects of Cellular Ca2+ Mobilization
by Wei Zhang, Terunao Takahara, Takuya Achiha, Hideki Shibata and Masatoshi Maki
Int. J. Mol. Sci. 2018, 19(2), 605; https://doi.org/10.3390/ijms19020605 - 18 Feb 2018
Cited by 5 | Viewed by 6194
Abstract
NFAT is a cytoplasm-localized hyper-phosphorylated transcription factor that is activated through dephosphorylation by calcineurin, a Ca2+/calmodulin-dependent phosphatase. A non-palindromic NFAT-response element (RE) found in the IL2 promoter region has been commonly used for a Ca2+-response reporter gene system, but [...] Read more.
NFAT is a cytoplasm-localized hyper-phosphorylated transcription factor that is activated through dephosphorylation by calcineurin, a Ca2+/calmodulin-dependent phosphatase. A non-palindromic NFAT-response element (RE) found in the IL2 promoter region has been commonly used for a Ca2+-response reporter gene system, but requirement of concomitant activation of AP-1 (Fos/Jun) often complicates the interpretation of obtained results. A new nanoluciferase (NanoLuc) reporter gene containing nine-tandem repeats of a pseudo-palindromic NFAT-RE located upstream of the IL8 promoter was designed to monitor Ca2+-induced transactivation activity of NFAT in human embryonic kidney (HEK) 293 cells by measuring luciferase activities of NanoLuc and co-expressed firefly luciferase for normalization. Ionomycin treatment enhanced the relative luciferase activity (RLA), which was suppressed by calcineurin inhibitors. HEK293 cells that stably express human STIM1 and Orai1, components of the store-operated calcium entry (SOCE) machinery, gave a much higher RLA by stimulation with thapsigargin, an inhibitor of sarcoplasmic/endoplamic reticulum Ca2+-ATPase (SERCA). HEK293 cells deficient in a penta-EF-hand Ca2+-binding protein ALG-2 showed a higher RLA value than the parental cells by stimulation with an acetylcholine receptor agonist carbachol. The novel reporter gene system is found to be useful for applications to cell signaling research to monitor biological endpoint effects of cellular Ca2+ mobilization. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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14 pages, 2879 KiB  
Article
Calbindin D28k-Immunoreactivity in Human Enteric Neurons
by Katharina Zetzmann, Johanna Strehl, Carol Geppert, Stefanie Kuerten, Samir Jabari and Axel Brehmer
Int. J. Mol. Sci. 2018, 19(1), 194; https://doi.org/10.3390/ijms19010194 - 08 Jan 2018
Cited by 14 | Viewed by 6499
Abstract
Calbindin (CALB) is well established as immunohistochemical marker for intrinsic primary afferent neurons in the guinea pig gut. Its expression by numerous human enteric neurons has been demonstrated but little is known about particular types of neurons immunoreactive for CALB. Here we investigated [...] Read more.
Calbindin (CALB) is well established as immunohistochemical marker for intrinsic primary afferent neurons in the guinea pig gut. Its expression by numerous human enteric neurons has been demonstrated but little is known about particular types of neurons immunoreactive for CALB. Here we investigated small and large intestinal wholemount sets of 26 tumor patients in order to evaluate (1) the proportion of CALB+ neurons in the total neuron population, (2) the colocalization of CALB with calretinin (CALR), somatostatin (SOM) and vasoactive intestinal peptide (VIP) and (3) the morphology of CALB+ neurons. CALB+ neurons represented a minority of myenteric neurons (small intestine: 31%; large intestine: 25%) and the majority of submucosal neurons (between 72 and 95%). In the submucosa, most CALB+ neurons co-stained for CALR and VIP (between 69 and 80%) or for SOM (between 20 and 3%). In the myenteric plexus, 85% of CALB+ neurons did not co-stain with the other markers investigated. An unequivocal correlation between CALB reactivity and neuronal morphology was found for myenteric type III neurons in the small intestine: uniaxonal neurons with long, slender and branched dendrites were generally positive for CALB. Since also other neurons displayed occasional CALB reactivity, this protein is not suited as an exclusive marker for type III neurons. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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Review

Jump to: Research

22 pages, 1660 KiB  
Review
Flux-Independent NMDAR Signaling: Molecular Mediators, Cellular Functions, and Complexities
by Pavel Montes de Oca Balderas
Int. J. Mol. Sci. 2018, 19(12), 3800; https://doi.org/10.3390/ijms19123800 - 29 Nov 2018
Cited by 32 | Viewed by 5886
Abstract
The glutamate (Glu) N-methyl-d-aspartate (NMDA) receptor (NMDAR) plays a critical role in synaptic communication given mainly by its ionotropic function that permeates Ca2+. This in turn activates calmodulin that triggers CaMKII, MAPK, CREB, and PI3K pathways, among others. However, [...] Read more.
The glutamate (Glu) N-methyl-d-aspartate (NMDA) receptor (NMDAR) plays a critical role in synaptic communication given mainly by its ionotropic function that permeates Ca2+. This in turn activates calmodulin that triggers CaMKII, MAPK, CREB, and PI3K pathways, among others. However, NMDAR signaling is more complex. In the last two decades several groups have shown that the NMDAR also elicits flux-independent signaling (f-iNMDARs). It has been demonstrated that agonist (Glu or NMDA) or co-agonist (Glycine or d-Serine) bindings initiate intracellular events, including conformational changes, exchange of molecular interactions, release of second messengers, and signal transduction, that result in different cellular events including endocytosis, LTD, cell death, and neuroprotection, among others. Interestingly, f-iNMDARs has also been observed in pathological conditions and non-neuronal cells. Here, the molecular and cellular events elicited by these flux-independent actions (non-canonical or metabotropic-like) of the NMDAR are reviewed. Considering the NMDAR complexity, it is possible that these flux-independent events have a more relevant role in intracellular signaling that has been disregarded for decades. Moreover, considering the wide expression and function of the NMDAR in non-neuronal cells and other tissues beyond the nervous system and some evolutionary traits, f-iNMDARs calls for a reconsideration of how we understand the biology of this complex receptor. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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21 pages, 738 KiB  
Review
Voltage-Dependent Calcium Channels, Calcium Binding Proteins, and Their Interaction in the Pathological Process of Epilepsy
by Jie-Hua Xu and Feng-Ru Tang
Int. J. Mol. Sci. 2018, 19(9), 2735; https://doi.org/10.3390/ijms19092735 - 12 Sep 2018
Cited by 37 | Viewed by 6305
Abstract
As an important second messenger, the calcium ion (Ca2+) plays a vital role in normal brain function and in the pathophysiological process of different neurodegenerative diseases including Alzheimer’s disease (AD), Parkinson’s disease (PD), and epilepsy. Ca2+ takes part in the [...] Read more.
As an important second messenger, the calcium ion (Ca2+) plays a vital role in normal brain function and in the pathophysiological process of different neurodegenerative diseases including Alzheimer’s disease (AD), Parkinson’s disease (PD), and epilepsy. Ca2+ takes part in the regulation of neuronal excitability, and the imbalance of intracellular Ca2+ is a trigger factor for the occurrence of epilepsy. Several anti-epileptic drugs target voltage-dependent calcium channels (VDCCs). Intracellular Ca2+ levels are mainly controlled by VDCCs located in the plasma membrane, the calcium-binding proteins (CBPs) inside the cytoplasm, calcium channels located on the intracellular calcium store (particular the endoplasmic reticulum/sarcoplasmic reticulum), and the Ca2+-pumps located in the plasma membrane and intracellular calcium store. So far, while many studies have established the relationship between calcium control factors and epilepsy, the mechanism of various Ca2+ regulatory factors in epileptogenesis is still unknown. In this paper, we reviewed the function, distribution, and alteration of VDCCs and CBPs in the central nervous system in the pathological process of epilepsy. The interaction of VDCCs with CBPs in the pathological process of epilepsy was also summarized. We hope this review can provide some clues for better understanding the mechanism of epileptogenesis, and for the development of new anti-epileptic drugs targeting on VDCCs and CBPs. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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20 pages, 3581 KiB  
Review
Unique Ca2+-Cycling Protein Abundance and Regulation Sustains Local Ca2+ Releases and Spontaneous Firing of Rabbit Sinoatrial Node Cells
by Tatiana M. Vinogradova, Syevda Tagirova (Sirenko) and Edward G. Lakatta
Int. J. Mol. Sci. 2018, 19(8), 2173; https://doi.org/10.3390/ijms19082173 - 25 Jul 2018
Cited by 12 | Viewed by 4201
Abstract
Spontaneous beating of the heart pacemaker, the sinoatrial node, is generated by sinoatrial node cells (SANC) and caused by gradual change of the membrane potential called diastolic depolarization (DD). Submembrane local Ca2+ releases (LCR) from sarcoplasmic reticulum (SR) occur during late DD [...] Read more.
Spontaneous beating of the heart pacemaker, the sinoatrial node, is generated by sinoatrial node cells (SANC) and caused by gradual change of the membrane potential called diastolic depolarization (DD). Submembrane local Ca2+ releases (LCR) from sarcoplasmic reticulum (SR) occur during late DD and activate an inward Na+/Ca2+ exchange current, which accelerates the DD rate leading to earlier occurrence of an action potential. A comparison of intrinsic SR Ca2+ cycling revealed that, at similar physiological Ca2+ concentrations, LCRs are large and rhythmic in permeabilized SANC, but small and random in permeabilized ventricular myocytes (VM). Permeabilized SANC spontaneously released more Ca2+ from SR than VM, despite comparable SR Ca2+ content in both cell types. In this review we discuss specific patterns of expression and distribution of SR Ca2+ cycling proteins (SR Ca2+ ATPase (SERCA2), phospholamban (PLB) and ryanodine receptors (RyR)) in SANC and ventricular myocytes. We link ability of SANC to generate larger and rhythmic LCRs with increased abundance of SERCA2, reduced abundance of the SERCA inhibitor PLB. In addition, an increase in intracellular [Ca2+] increases phosphorylation of both PLB and RyR exclusively in SANC. The differences in SR Ca2+ cycling protein expression between SANC and VM provide insights into diverse regulation of intrinsic SR Ca2+ cycling that drives automaticity of SANC. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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18 pages, 1074 KiB  
Review
Towards Understanding Plant Calcium Signaling through Calmodulin-Like Proteins: A Biochemical and Structural Perspective
by Valentina La Verde, Paola Dominici and Alessandra Astegno
Int. J. Mol. Sci. 2018, 19(5), 1331; https://doi.org/10.3390/ijms19051331 - 30 Apr 2018
Cited by 63 | Viewed by 6853
Abstract
Ca2+ ions play a key role in a wide variety of environmental responses and developmental processes in plants, and several protein families with Ca2+-binding domains have evolved to meet these needs, including calmodulin (CaM) and calmodulin-like proteins (CMLs). These proteins [...] Read more.
Ca2+ ions play a key role in a wide variety of environmental responses and developmental processes in plants, and several protein families with Ca2+-binding domains have evolved to meet these needs, including calmodulin (CaM) and calmodulin-like proteins (CMLs). These proteins have no catalytic activity, but rather act as sensor relays that regulate downstream targets. While CaM is well-studied, CMLs remain poorly characterized at both the structural and functional levels, even if they are the largest class of Ca2+ sensors in plants. The major structural theme in CMLs consists of EF-hands, and variations in these domains are predicted to significantly contribute to the functional versatility of CMLs. Herein, we focus on recent advances in understanding the features of CMLs from biochemical and structural points of view. The analysis of the metal binding and structural properties of CMLs can provide valuable insight into how such a vast array of CML proteins can coexist, with no apparent functional redundancy, and how these proteins contribute to cellular signaling while maintaining properties that are distinct from CaM and other Ca2+ sensors. An overview of the principal techniques used to study the biochemical properties of these interesting Ca2+ sensors is also presented. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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16 pages, 822 KiB  
Review
Ca2+ Regulation of TRP Ion Channels
by Raquibul Hasan and Xuming Zhang
Int. J. Mol. Sci. 2018, 19(4), 1256; https://doi.org/10.3390/ijms19041256 - 23 Apr 2018
Cited by 60 | Viewed by 6315
Abstract
Ca2+ signaling influences nearly every aspect of cellular life. Transient receptor potential (TRP) ion channels have emerged as cellular sensors for thermal, chemical and mechanical stimuli and are major contributors to Ca2+ signaling, playing an important role in diverse physiological and [...] Read more.
Ca2+ signaling influences nearly every aspect of cellular life. Transient receptor potential (TRP) ion channels have emerged as cellular sensors for thermal, chemical and mechanical stimuli and are major contributors to Ca2+ signaling, playing an important role in diverse physiological and pathological processes. Notably, TRP ion channels are also one of the major downstream targets of Ca2+ signaling initiated either from TRP channels themselves or from various other sources, such as G-protein coupled receptors, giving rise to feedback regulation. TRP channels therefore function like integrators of Ca2+ signaling. A growing body of research has demonstrated different modes of Ca2+-dependent regulation of TRP ion channels and the underlying mechanisms. However, the precise actions of Ca2+ in the modulation of TRP ion channels remain elusive. Advances in Ca2+ regulation of TRP channels are critical to our understanding of the diversified functions of TRP channels and complex Ca2+ signaling. Full article
(This article belongs to the Special Issue Calcium Binding Proteins)
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