1
|
Terrar DA. Calcium flux balance across cell membranes in the heart: important unanswered questions with implications for the role of ryanodine receptors. J Physiol 2024. [PMID: 39097828 DOI: 10.1113/jp287223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2024] [Accepted: 07/12/2024] [Indexed: 08/05/2024] Open
Affiliation(s)
- Derek A Terrar
- Department of Pharmacology, University of Oxford, Oxford, UK
- UCL Institute of Cardiovascular Science, University College London, London, UK
| |
Collapse
|
2
|
Kramer DJ, Johnson AA. Apigenin: a natural molecule at the intersection of sleep and aging. Front Nutr 2024; 11:1359176. [PMID: 38476603 PMCID: PMC10929570 DOI: 10.3389/fnut.2024.1359176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Accepted: 01/30/2024] [Indexed: 03/14/2024] Open
Abstract
NAD+, a pivotal coenzyme central to metabolism, exhibits a characteristic decline with age. In mice, NAD+ levels can be elevated via treatment with apigenin, a natural flavonoid that inhibits the NAD+-consuming glycoprotein CD38. In animal models, apigenin positively impacts both sleep and longevity. For example, apigenin improves learning and memory in older mice, reduces tumor proliferation in a mouse xenograft model of triple-negative breast cancer, and induces sedative effects in mice and rats. Moreover, apigenin elongates survival in fly models of neurodegenerative disease and apigenin glycosides increase lifespan in worms. Apigenin's therapeutic potential is underscored by human clinical studies using chamomile extract, which contains apigenin as an active ingredient. Collectively, chamomile extract has been reported to alleviate anxiety, improve mood, and relieve pain. Furthermore, dietary apigenin intake positively correlates with sleep quality in a large cohort of adults. Apigenin's electron-rich flavonoid structure gives it strong bonding capacity to diverse molecular structures across receptors and enzymes. The effects of apigenin extend beyond CD38 inhibition, encompassing agonistic and antagonistic modulation of various targets, including GABA and inflammatory pathways. Cumulatively, a large body of evidence positions apigenin as a unique molecule capable of influencing both aging and sleep. Further studies are warranted to better understand apigenin's nuanced mechanisms and clinical potential.
Collapse
|
3
|
Eastman S, Bayless A, Guo M. The Nucleotide Revolution: Immunity at the Intersection of Toll/Interleukin-1 Receptor Domains, Nucleotides, and Ca 2. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2022; 35:964-976. [PMID: 35881867 DOI: 10.1094/mpmi-06-22-0132-cr] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The discovery of the enzymatic activity of the toll/interleukin-1 receptor (TIR) domain protein SARM1 five years ago preceded a flood of discoveries regarding the nucleotide substrates and products of TIR domains in plants, animals, bacteria, and archaea. These discoveries into the activity of TIR domains coincide with major advances in understanding the structure and mechanisms of NOD-like receptors and the mutual dependence of pattern recognition receptor- and effector-triggered immunity (PTI and ETI, respectively) in plants. It is quickly becoming clear that TIR domains and TIR-produced nucleotides are ancestral signaling molecules that modulate immunity and that their activity is closely associated with Ca2+ signaling. TIR domain research now bridges the separate disciplines of molecular plant- and animal-microbe interactions, neurology, and prokaryotic immunity. A cohesive framework for understanding the role of enzymatic TIR domains in diverse organisms will help unite the research of these disparate fields. Here, we review known products of TIR domains in plants, animals, bacteria, and archaea and use context gained from animal and prokaryotic TIR domain systems to present a model for TIR domains, nucleotides, and Ca2+ at the intersection of PTI and ETI in plant immunity. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.
Collapse
Affiliation(s)
- Samuel Eastman
- Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE 68583, U.S.A
| | - Adam Bayless
- Department of Biology, Colorado State University, Fort Collins, CO 80521, U.S.A
| | - Ming Guo
- Department of Agriculture and Horticulture, University of Nebraska-Lincoln, Lincoln, NE 68583, U.S.A
| |
Collapse
|
4
|
Waller TJ, Collins CA. Multifaceted roles of SARM1 in axon degeneration and signaling. Front Cell Neurosci 2022; 16:958900. [PMID: 36090788 PMCID: PMC9453223 DOI: 10.3389/fncel.2022.958900] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 08/09/2022] [Indexed: 12/01/2022] Open
Abstract
Axons are considered to be particularly vulnerable components of the nervous system; impairments to a neuron’s axon leads to an effective silencing of a neuron’s ability to communicate with other cells. Nervous systems have therefore evolved plasticity mechanisms for adapting to axonal damage. These include acute mechanisms that promote the degeneration and clearance of damaged axons and, in some cases, the initiation of new axonal growth and synapse formation to rebuild lost connections. Here we review how these diverse processes are influenced by the therapeutically targetable enzyme SARM1. SARM1 catalyzes the breakdown of NAD+, which, when unmitigated, can lead to rundown of this essential metabolite and axonal degeneration. SARM1’s enzymatic activity also triggers the activation of downstream signaling pathways, which manifest numerous functions for SARM1 in development, innate immunity and responses to injury. Here we will consider the multiple intersections between SARM1 and the injury signaling pathways that coordinate cellular adaptations to nervous system damage.
Collapse
Affiliation(s)
- Thomas J. Waller
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
| | - Catherine A. Collins
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, United States
- Department of Neurosciences, Case Western Reserve University, Cleveland, OH, United States
- *Correspondence: Catherine A. Collins,
| |
Collapse
|
5
|
Leseigneur C, Boucontet L, Duchateau M, Pizarro-Cerda J, Matondo M, Colucci-Guyon E, Dussurget O. NAD kinase promotes Staphylococcus aureus pathogenesis by supporting production of virulence factors and protective enzymes. eLife 2022; 11:79941. [PMID: 35723663 PMCID: PMC9208755 DOI: 10.7554/elife.79941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Nicotinamide adenine dinucleotide phosphate (NADPH) is the primary electron donor for reductive reactions that are essential for the biosynthesis of major cell components in all organisms. Nicotinamide adenine dinucleotide kinase (NADK) is the only enzyme that catalyzes the synthesis of NADP(H) from NAD(H). While the enzymatic properties and physiological functions of NADK have been thoroughly studied, the role of NADK in bacterial pathogenesis remains unknown. Here, we used CRISPR interference to knock down NADK gene expression to address the role of this enzyme in Staphylococcus aureus pathogenic potential. We find that NADK inhibition drastically decreases mortality of zebrafish infected with S. aureus. Furthermore, we show that NADK promotes S. aureus survival in infected macrophages by protecting bacteria from antimicrobial defense mechanisms. Proteome-wide data analysis revealed that production of major virulence-associated factors is sustained by NADK. We demonstrate that NADK is required for expression of the quorum-sensing response regulator AgrA, which controls critical S. aureus virulence determinants. These findings support a key role for NADK in bacteria survival within innate immune cells and the host during infection.
Collapse
Affiliation(s)
- Clarisse Leseigneur
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, Paris, France
| | - Laurent Boucontet
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Unité Macrophages et Développement de l'Immunité, Paris, France
| | - Magalie Duchateau
- Institut Pasteur, Université Paris Cité, CNRS USR2000, Unité de Spectrométrie de Masse pour la Biologie, Plateforme de protéomique, Paris, France
| | - Javier Pizarro-Cerda
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, Paris, France
| | - Mariette Matondo
- Institut Pasteur, Université Paris Cité, CNRS USR2000, Unité de Spectrométrie de Masse pour la Biologie, Plateforme de protéomique, Paris, France
| | - Emma Colucci-Guyon
- Institut Pasteur, Université Paris Cité, CNRS UMR3738, Unité Macrophages et Développement de l'Immunité, Paris, France
| | - Olivier Dussurget
- Institut Pasteur, Université Paris Cité, CNRS UMR6047, Unité de Recherche Yersinia, Paris, France
| |
Collapse
|
6
|
Barbonari S, D'Amore A, Palombi F, De Cesaris P, Parrington J, Riccioli A, Filippini A. RELEVANCE OF LYSOSOMAL Ca2+ SIGNALLING MACHINERY IN CANCER. Cell Calcium 2022; 102:102539. [DOI: 10.1016/j.ceca.2022.102539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 01/05/2022] [Accepted: 01/06/2022] [Indexed: 12/23/2022]
|
7
|
Cai R, Chen XZ. Roles of Intramolecular Interactions in the Regulation of TRP Channels. Rev Physiol Biochem Pharmacol 2022; 186:29-56. [PMID: 35882668 DOI: 10.1007/112_2022_74] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The transient receptor potential (TRP) channels, classified into six (-A, -V, -P, -C, -M, -ML, -N and -Y) subfamilies, are important membrane sensors and mediators of diverse stimuli including pH, light, mechano-force, temperature, pain, taste, and smell. The mammalian TRP superfamily of 28 members share similar membrane topology with six membrane-spanning helices (S1-S6) and cytosolic N-/C-terminus. Abnormal function or expression of TRP channels is associated with cancer, skeletal dysplasia, immunodeficiency, and cardiac, renal, and neuronal diseases. The majority of TRP members share common functional regulators such as phospholipid PIP2, 2-aminoethoxydiphenyl borate (2-APB), and cannabinoid, while other ligands are more specific, such as allyl isothiocyanate (TRPA1), vanilloids (TRPV1), menthol (TRPM8), ADP-ribose (TRPM2), and ML-SA1 (TRPML1). The mechanisms underlying the gating and regulation of TRP channels remain largely unclear. Recent advances in cryogenic electron microscopy provided structural insights into 19 different TRP channels which all revealed close proximity of the C-terminus with the N-terminus and intracellular S4-S5 linker. Further studies found that some highly conserved residues in these regions of TRPV, -P, -C and -M members mediate functionally critical intramolecular interactions (i.e., within one subunit) between these regions. This review provides an overview on (1) intramolecular interactions in TRP channels and their effect on channel function; (2) functional roles of interplays between PIP2 (and other ligands) and TRP intramolecular interactions; and (3) relevance of the ligand-induced modulation of intramolecular interaction to diseases.
Collapse
Affiliation(s)
- Ruiqi Cai
- Program in Cell Biology, Peter Gilgan Centre for Research and Learning, Hospital for Sick Children, Toronto, ON, Canada.,Department of Physiology, Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB, Canada
| | - Xing-Zhen Chen
- Department of Physiology, Membrane Protein Disease Research Group, University of Alberta, Edmonton, AB, Canada.
| |
Collapse
|
8
|
Davis LC, Morgan AJ, Galione A. Acidic Ca 2+ stores and immune-cell function. Cell Calcium 2021; 101:102516. [PMID: 34922066 DOI: 10.1016/j.ceca.2021.102516] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/03/2021] [Accepted: 12/04/2021] [Indexed: 12/11/2022]
Abstract
Acidic organelles act as intracellular Ca2+ stores; they actively sequester Ca2+ in their lumina and release it to the cytosol upon activation of endo-lysosomal Ca2+ channels. Recent data suggest important roles of endo-lysosomal Ca2+ channels, the Two-Pore Channels (TPCs) and the TRPML channels (mucolipins), in different aspects of immune-cell function, particularly impacting membrane trafficking, vesicle fusion/fission and secretion. Remarkably, different channels on the same acidic vesicles can couple to different downstream physiology. Endo-lysosomal Ca2+ stores can act under different modalities, be they acting alone (via local Ca2+ nanodomains around TPCs/TRPMLs) or in conjunction with the ER Ca2+ store (to either promote or suppress global ER Ca2+ release). These different modalities impinge upon functions as broad as phagocytosis, cell-killing, anaphylaxis, immune memory, thrombostasis, and chemotaxis.
Collapse
Affiliation(s)
- Lianne C Davis
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK.
| | - Anthony J Morgan
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK
| | - Antony Galione
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK.
| |
Collapse
|
9
|
Fomina AF. Neglected wardens: T lymphocyte ryanodine receptors. J Physiol 2021; 599:4415-4426. [PMID: 34411300 DOI: 10.1113/jp281722] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 06/22/2021] [Indexed: 12/14/2022] Open
Abstract
Ryanodine receptors (RyRs) are intracellular Ca2+ release channels ubiquitously expressed in various cell types. RyRs were extensively studied in striated muscle cells due to their crucial role in muscle contraction. In contrast, the role of RyRs in Ca2+ signalling and functions in non-excitable cells, such as T lymphocytes, remains poorly understood. Expression of different isoforms of RyRs was shown in primary T cells and T cell lines. In T cells, RyRs co-localize with the plasmalemmal store-operated Ca2+ channels of the Orai family and endoplasmic reticulum Ca2+ sensing Stim family proteins and are activated by store-operated Ca2+ entry and pyridine nucleotide metabolites, the intracellular second messengers generated upon stimulation of T cell receptors. Experimental data indicate that together with d-myo-inositol 1,4,5-trisphosphate receptors, RyRs regulate intercellular Ca2+ dynamics by controlling Ca2+ concentration within the lumen of the endoplasmic reticulum and, consequently, store-operated Ca2+ entry. Gain-of-function mutations, genetic deletion or pharmacological inhibition of RyRs alters T cell Ca2+ signalling and effector functions. The picture emerging from the collective data shows that RyRs are the essential regulators of T cell Ca2+ signalling and can be potentially used as molecular targets for immunomodulation or T cell-based diagnostics of the disorders associated with RyRs dysregulation.
Collapse
Affiliation(s)
- Alla F Fomina
- Department of Physiology and Membrane Biology, University of California, Davis, CA, USA
| |
Collapse
|
10
|
Gao L, Liu Y, Du X, Ma S, Ge M, Tang H, Han C, Zhao X, Liu Y, Shao Y, Wu Z, Zhang L, Meng F, Xiao-Feng Qin F. The intrinsic role and mechanism of tumor expressed-CD38 on lung adenocarcinoma progression. Cell Death Dis 2021; 12:680. [PMID: 34226519 PMCID: PMC8256983 DOI: 10.1038/s41419-021-03968-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/23/2021] [Accepted: 06/23/2021] [Indexed: 12/12/2022]
Abstract
It has been recently reported that CD38 expressed on tumor cells of multiple murine and human origins could be upregulated in response to PD-L1 antibody therapy, which led to dysfunction of tumor-infiltrating CD8+ T immune cells due to increasing the production of adenosine. However, the role of tumor expressed-CD38 on neoplastic formation and progression remains elusive. In the present study, we aimed to delineate the molecular and biochemical function of the tumor-associated CD38 in lung adenocarcinoma progression. Our clinical data showed that the upregulation of tumor-originated CD38 was correlated with poor survival of lung cancer patients. Using multiple in vitro assays we found that the enzymatic activity of tumor expressed-CD38 facilitated lung cancer cell migration, proliferation, colony formation, and tumor development. Consistently, our in vivo results showed that inhibition of the enzymatic activity or antagonizing the enzymatic product of CD38 resulted in the similar inhibition of tumor proliferation and metastasis as CD38 gene knock-out or mutation. At biochemical level, we further identified that cADPR, the mainly hydrolytic product of CD38, was responsible for inducing the opening of TRPM2 iron channel leading to the influx of intracellular Ca2+ and then led to increasing levels of NRF2 while decreasing expression of KEAP1 in lung cancer cells. These findings suggested that malignant lung cancer cells were capable of using cADPR catalyzed by CD38 to facilitate tumor progression, and blocking the enzymatic activity of CD38 could be represented as an important strategy for preventing tumor progression.
Collapse
Affiliation(s)
- Long Gao
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Yuan Liu
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Xiaohong Du
- Institute of Clinical Medicine Research, the Affiliated Suzhou Hospital of Nanjing Medical University; Suzhou Science and Technology Town Hospital, Suzhou, China
| | - Sai Ma
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Minmin Ge
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Haijun Tang
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Chenfeng Han
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Xin Zhao
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Yanbin Liu
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Yun Shao
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Zhao Wu
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Lianjun Zhang
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China
| | - Fang Meng
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China.
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China.
| | - F Xiao-Feng Qin
- Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China.
- Suzhou Institute of Systems Medicine, Suzhou, 215123, Jiangsu, China.
| |
Collapse
|
11
|
SARM1 signaling mechanisms in the injured nervous system. Curr Opin Neurobiol 2021; 69:247-255. [PMID: 34175654 DOI: 10.1016/j.conb.2021.05.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/18/2021] [Accepted: 05/24/2021] [Indexed: 11/21/2022]
Abstract
Axon degeneration is a prominent feature of the injured nervous system, occurs across neurological diseases, and drives functional loss in neural circuits. We have seen a paradigm shift in the last decade with the realization that injured axons are capable of actively driving their own destruction through the sterile-alpha and TIR motif containing 1 (SARM1) protein. Early studies of Wallerian degeneration highlighted a central role for NAD+ metabolites in axon survival, and this association has grown even stronger in recent years with a deeper understanding of SARM1 biology. Here, we review our current knowledge of SARM1 function in vivo and our evolving understanding of its complex architecture and regulation by injury-dependent changes in the local metabolic environment. The field is converging on a model whereby SARM1 acts as a sensor for metabolic changes that occur after injury and then drives catastrophic NAD+ loss to promote degeneration. However, a number of observations suggest that SARM1 biology is more complicated, and there remains much to learn about how SARM1 governs nervous system responses to injury or disease.
Collapse
|
12
|
Corkidi G, Hernández-Herrera P, Montoya F, Gadêlha H, Darszon A. Long-term segmentation-free assessment of head-flagellum movement and intracellular calcium in swimming human sperm. J Cell Sci 2021; 134:jcs.250654. [PMID: 33431515 DOI: 10.1242/jcs.250654] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 12/14/2020] [Indexed: 12/31/2022] Open
Abstract
Human spermatozoa are the archetype of long-term self-organizing transport in nature and are critical for reproductive success. They utilize coordinated head and flagellar movements to swim long distances within the female reproductive tract in order to find and fertilize the egg. However, to date, long-term analysis of the sperm head-flagellar movements, or indeed those of other flagellated microorganisms, remains elusive due to limitations in microscopy and flagellar-tracking techniques. Here, we present a novel methodology based on local orientation and isotropy of bio-images to obtain long-term kinematic and physiological parameters of individual free-swimming spermatozoa without requiring image segmentation (thresholding). This computer-assisted segmentation-free method evaluates, for the first time, characteristics of the head movement and flagellar beating for up to 9.2 min. We demonstrate its powerful use by showing how releasing Ca2+ from internal stores significantly alters long-term sperm behavior. The method allows for straightforward generalization to other bio-imaging applications, such as studies of bull sperm and Trypanosoma, or indeed of other flagellated microorganisms - appealing to communities other than those investigating sperm biology.
Collapse
Affiliation(s)
- Gabriel Corkidi
- Laboratorio de Imágenes y Visión por Computadora, Departamento de Ingenería Celular y Biocatálisis, Instituto de Biotecnología, UNAM, 62210 Cuernavaca, México
| | - Paul Hernández-Herrera
- Laboratorio de Imágenes y Visión por Computadora, Departamento de Ingenería Celular y Biocatálisis, Instituto de Biotecnología, UNAM, 62210 Cuernavaca, México
| | - Fernando Montoya
- Laboratorio de Imágenes y Visión por Computadora, Departamento de Ingenería Celular y Biocatálisis, Instituto de Biotecnología, UNAM, 62210 Cuernavaca, México
| | - Hermes Gadêlha
- Department of Engineering Mathematics & Bristol Robotics Laboratory, University of Bristol, Bristol BS8 1QU, UK
| | - Alberto Darszon
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, UNAM, 62210 Cuernavaca, México
| |
Collapse
|
13
|
Molecular Mechanisms of Calcium Signaling During Phagocytosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1246:103-128. [PMID: 32399828 DOI: 10.1007/978-3-030-40406-2_7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Calcium (Ca2+) is a ubiquitous second messenger involved in the regulation of numerous cellular functions including vesicular trafficking, cytoskeletal rearrangements and gene transcription. Both global as well as localized Ca2+ signals occur during phagocytosis, although their functional impact on the phagocytic process has been debated. After nearly 40 years of research, a consensus may now be reached that although not strictly required, Ca2+ signals render phagocytic ingestion and phagosome maturation more efficient, and their manipulation make an attractive avenue for therapeutic interventions. In the last decade many efforts have been made to identify the channels and regulators involved in generating and shaping phagocytic Ca2+ signals. While molecules involved in store-operated calcium entry (SOCE) of the STIM and ORAI family have taken center stage, members of the canonical, melastatin, mucolipin and vanilloid transient receptor potential (TRP), as well as purinergic P2X receptor families are now recognized to play significant roles. In this chapter, we review the recent literature on research that has linked specific Ca2+-permeable channels and regulators to phagocytic function. We highlight the fact that lipid mediators are emerging as important regulators of channel gating and that phagosomal ionic homeostasis and Ca2+ release also play essential parts. We predict that improved methodologies for measuring these factors will be critical for future advances in dissecting the intricate biology of this fascinating immune process.
Collapse
|