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Albarano L, Zupo V, Guida M, Libralato G, Caramiello D, Ruocco N, Costantini M. PAHs and PCBs Affect Functionally Intercorrelated Genes in the Sea Urchin Paracentrotus lividus Embryos. Int J Mol Sci 2021; 22:ijms222212498. [PMID: 34830379 PMCID: PMC8619768 DOI: 10.3390/ijms222212498] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 11/15/2021] [Accepted: 11/18/2021] [Indexed: 01/05/2023] Open
Abstract
Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) represent the most common pollutants in the marine sediments. Previous investigations demonstrated short-term sublethal effects of sediments polluted with both contaminants on the sea urchin Paracentrotus lividus after 2 months of exposure in mesocosms. In particular, morphological malformations observed in P. lividus embryos deriving from adults exposed to PAHs and PCBs were explained at molecular levels by de novo transcriptome assembly and real-time qPCR, leading to the identification of several differentially expressed genes involved in key physiological processes. Here, we extensively explored the genes involved in the response of the sea urchin P. lividus to PAHs and PCBs. Firstly, 25 new genes were identified and interactomic analysis revealed that they were functionally connected among them and to several genes previously defined as molecular targets of response to the two pollutants under analysis. The expression levels of these 25 genes were followed by Real Time qPCR, showing that almost all genes analyzed were affected by PAHs and PCBs. These findings represent an important further step in defining the impacts of slight concentrations of such contaminants on sea urchins and, more in general, on marine biota, increasing our knowledge of molecular targets involved in responses to environmental stressors.
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Affiliation(s)
- Luisa Albarano
- Stazione Zoologica Anton Dohrn, Department of Marine Biotechnology, Villa Comunale, 80121 Naples, Italy; (L.A.); (G.L.); (N.R.)
- Department of Biology, University of Naples Federico II, Complesso di Monte Sant’Angelo, Via Cinthia 21, 80126 Naples, Italy;
| | - Valerio Zupo
- Stazione Zoologica Anton Dohrn, Department of Marine Biotechnology, Villa Dohrn, Punta San Pietro, 80077 Naples, Italy;
| | - Marco Guida
- Department of Biology, University of Naples Federico II, Complesso di Monte Sant’Angelo, Via Cinthia 21, 80126 Naples, Italy;
- Centro Servizi Metrologici e Tecnologici Avanzati (CeSMA), Complesso Universitario di Monte Sant’Angelo, Via Cinthia 21, 80126 Naples, Italy
| | - Giovanni Libralato
- Stazione Zoologica Anton Dohrn, Department of Marine Biotechnology, Villa Comunale, 80121 Naples, Italy; (L.A.); (G.L.); (N.R.)
- Department of Biology, University of Naples Federico II, Complesso di Monte Sant’Angelo, Via Cinthia 21, 80126 Naples, Italy;
| | - Davide Caramiello
- Stazione Zoologica Anton Dohrn, Department of Research Infrastructures for Marine Biological Resources, Marine Organisms Core Facility, Villa Comunale, 80121 Naples, Italy;
| | - Nadia Ruocco
- Stazione Zoologica Anton Dohrn, Department of Marine Biotechnology, Villa Comunale, 80121 Naples, Italy; (L.A.); (G.L.); (N.R.)
- Stazione Zoologica Anton Dohrn, Department of Marine Biotechnology, C. da Torre Spaccata, 87071 Amendolara, Italy
| | - Maria Costantini
- Stazione Zoologica Anton Dohrn, Department of Marine Biotechnology, Villa Comunale, 80121 Naples, Italy; (L.A.); (G.L.); (N.R.)
- Correspondence:
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Albarano L, Zupo V, Caramiello D, Toscanesi M, Trifuoggi M, Guida M, Libralato G, Costantini M. Sub-Chronic Effects of Slight PAH- and PCB-Contaminated Mesocosms in Paracentrotus lividus Lmk: A Multi-Endpoint Approach and De Novo Transcriptomic. Int J Mol Sci 2021; 22:ijms22136674. [PMID: 34206685 PMCID: PMC8268688 DOI: 10.3390/ijms22136674] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/16/2021] [Accepted: 06/18/2021] [Indexed: 11/26/2022] Open
Abstract
Sediment pollution is a major issue in coastal areas, potentially endangering human health and the marine environments. We investigated the short-term sublethal effects of sediments contaminated with polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) on the sea urchin Paracentrotus lividus for two months. Spiking occurred at concentrations below threshold limit values permitted by the law (TLVPAHs = 900 µg/L, TLVPCBs = 8 µg/L, Legislative Italian Decree 173/2016). A multi-endpoint approach was adopted, considering both adults (mortality, bioaccumulation and gonadal index) and embryos (embryotoxicity, genotoxicity and de novo transcriptome assembly). The slight concentrations of PAHs and PCBs added to the mesocosms were observed to readily compartmentalize in adults, resulting below the detection limits just one week after their addition. Reconstructed sediment and seawater, as negative controls, did not affect sea urchins. PAH- and PCB-spiked mesocosms were observed to impair P. lividus at various endpoints, including bioaccumulation and embryo development (mainly PAHs) and genotoxicity (PAHs and PCBs). In particular, genotoxicity tests revealed that PAHs and PCBs affected the development of P. lividus embryos deriving from exposed adults. Negative effects were also detected by generating a de novo transcriptome assembly and its annotation, as well as by real-time qPCR performed to identify genes differentially expressed in adults exposed to the two contaminants. The effects on sea urchins (both adults and embryos) at background concentrations of PAHs and PCBs below TLV suggest a need for further investigations on the impact of slight concentrations of such contaminants on marine biota.
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Affiliation(s)
- Luisa Albarano
- Stazione Zoologica Anton Dohrn, Department of Marine Biotechnology, Villa Comunale, 80121 Naples, Italy; (L.A.); (G.L.)
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte Sant’Angelo, Via Cinthia 21, 80126 Naples, Italy;
| | - Valerio Zupo
- Stazione Zoologica Anton Dohrn, Department of Marine Biotechnology, Villa Dohrn, Punta San Pietro, 80077 Naples, Italy;
| | - Davide Caramiello
- Stazione Zoologica Anton Dohrn, Department of Research Infrastructures for Marine Biological Resources, Marine Organisms Core Facility, Villa Comunale, 80121 Naples, Italy;
| | - Maria Toscanesi
- Dipartimento di Scienze Chimiche, Università degli Studi di Napoli Federico II, Complesso Universitario di Monte S. Angelo, Via Cintia, 80126 Naples, Italy; (M.T.); (M.T.)
| | - Marco Trifuoggi
- Dipartimento di Scienze Chimiche, Università degli Studi di Napoli Federico II, Complesso Universitario di Monte S. Angelo, Via Cintia, 80126 Naples, Italy; (M.T.); (M.T.)
| | - Marco Guida
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte Sant’Angelo, Via Cinthia 21, 80126 Naples, Italy;
| | - Giovanni Libralato
- Stazione Zoologica Anton Dohrn, Department of Marine Biotechnology, Villa Comunale, 80121 Naples, Italy; (L.A.); (G.L.)
- Department of Biology, University of Naples Federico II, Complesso Universitario di Monte Sant’Angelo, Via Cinthia 21, 80126 Naples, Italy;
| | - Maria Costantini
- Stazione Zoologica Anton Dohrn, Department of Marine Biotechnology, Villa Comunale, 80121 Naples, Italy; (L.A.); (G.L.)
- Correspondence:
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3
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Jones KT. Mammalian sperm contain two factors for calcium release and egg activation: Phospholipase C zeta and a cryptic activating factor. Mol Hum Reprod 2019; 24:465-468. [PMID: 30257016 DOI: 10.1093/molehr/gay038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 08/22/2018] [Indexed: 12/11/2022] Open
Affiliation(s)
- Keith T Jones
- Faculty of Sciences, University of Adelaide, 5005, South Australia, Australia, and School of Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, UK
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Abstract
The most fundamental unresolved issue of fertilization is to define how the sperm activates the egg to begin embryo development. Egg activation at fertilization in all species thus far examined is caused by some form of transient increase in the cytoplasmic free Ca2+ concentration. What has not been clear, however, is precisely how the sperm triggers the large changes in Ca2+ observed within the egg cytoplasm. Here, we review the studies indicating that the fertilizing sperm stimulates a cytosolic Ca2+ increase in the egg specifically by delivering a soluble factor that diffuses into the cytosolic space of the egg upon gamete membrane fusion. Evidence is primarily considered in species of eggs where the sperm has been shown to elicit a cytosolic Ca2+ increase by initiating Ca2+ release from intracellular Ca2+ stores. We suggest that our best understanding of these signaling events is in mammals, where the sperm triggers a prolonged series of intracellular Ca2+ oscillations. The strongest empirical studies to date suggest that mammalian sperm-triggered Ca2+ oscillations are caused by the introduction of a sperm-specific protein, called phospholipase C-zeta (PLCζ) that generates inositol trisphosphate within the egg. We will discuss the role and mechanism of action of PLCζ in detail at a molecular and cellular level. We will also consider some of the evidence that a soluble sperm protein might be involved in egg activation in nonmammalian species.
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Affiliation(s)
- Karl Swann
- College of Biomedical and Life Sciences, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - F. Anthony Lai
- College of Biomedical and Life Sciences, School of Medicine, Cardiff University, Cardiff, United Kingdom
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5
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Darszon A, Nishigaki T, Beltran C, Treviño CL. Calcium Channels in the Development, Maturation, and Function of Spermatozoa. Physiol Rev 2011; 91:1305-55. [DOI: 10.1152/physrev.00028.2010] [Citation(s) in RCA: 243] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
A proper dialogue between spermatozoa and the egg is essential for conception of a new individual in sexually reproducing animals. Ca2+ is crucial in orchestrating this unique event leading to a new life. No wonder that nature has devised different Ca2+-permeable channels and located them at distinct sites in spermatozoa so that they can help fertilize the egg. New tools to study sperm ionic currents, and image intracellular Ca2+ with better spatial and temporal resolution even in swimming spermatozoa, are revealing how sperm ion channels participate in fertilization. This review critically examines the involvement of Ca2+ channels in multiple signaling processes needed for spermatozoa to mature, travel towards the egg, and fertilize it. Remarkably, these tiny specialized cells can express exclusive channels like CatSper for Ca2+ and SLO3 for K+, which are attractive targets for contraception and for the discovery of novel signaling complexes. Learning more about fertilization is a matter of capital importance; societies face growing pressure to counteract rising male infertility rates, provide safe male gamete-based contraceptives, and preserve biodiversity through improved captive breeding and assisted conception initiatives.
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Affiliation(s)
- Alberto Darszon
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Takuya Nishigaki
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Carmen Beltran
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
| | - Claudia L. Treviño
- Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México
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Rogasevskaia TP, Coorssen JR. A new approach to the molecular analysis of docking, priming, and regulated membrane fusion. J Chem Biol 2011; 4:117-36. [PMID: 22315653 DOI: 10.1007/s12154-011-0056-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Accepted: 12/23/2010] [Indexed: 12/12/2022] Open
Abstract
Studies using isolated sea urchin cortical vesicles have proven invaluable in dissecting mechanisms of Ca(2+)-triggered membrane fusion. However, only acute molecular manipulations are possible in vitro. Here, using selective pharmacological manipulations of sea urchin eggs ex vivo, we test the hypothesis that specific lipidic components of the membrane matrix selectively affect defined late stages of exocytosis, particularly the Ca(2+)-triggered steps of fast membrane fusion. Egg treatments with cholesterol-lowering drugs resulted in the inhibition of vesicle fusion. Exogenous cholesterol recovered fusion extent and efficiency in cholesterol-depleted membranes; α-tocopherol, a structurally dissimilar curvature analogue, selectively restored fusion extent. Inhibition of phospholipase C reduced vesicle phosphatidylethanolamine and suppressed both the extent and kinetics of fusion. Although phosphatidylinositol-3-kinase inhibition altered levels of polyphosphoinositide species and reduced all fusion parameters, sequestering polyphosphoinositides selectively inhibited fusion kinetics. Thus, cholesterol and phosphatidylethanolamine play direct roles in the fusion pathway, contributing negative curvature. Cholesterol also organizes the physiological fusion site, defining fusion efficiency. A selective influence of phosphatidylethanolamine on fusion kinetics sheds light on the local microdomain structure at the site of docking/fusion. Polyphosphoinositides have modulatory upstream roles in priming: alterations in specific polyphosphoinositides likely represent the terminal priming steps defining fully docked, release-ready vesicles. Thus, this pharmacological approach has the potential to be a robust high-throughput platform to identify molecular components of the physiological fusion machine critical to docking, priming, and triggered fusion.
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7
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Vasudevan SR, Lewis AM, Chan JW, Machin CL, Sinha D, Galione A, Churchill GC. The calcium-mobilizing messenger nicotinic acid adenine dinucleotide phosphate participates in sperm activation by mediating the acrosome reaction. J Biol Chem 2010; 285:18262-9. [PMID: 20400502 PMCID: PMC2881750 DOI: 10.1074/jbc.m109.087858] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Before a sperm can fertilize an egg it must undergo a final activation step induced by the egg termed the acrosome reaction. During the acrosome reaction a lysosome-related organelle, the acrosome, fuses with the plasma membrane to release hydrolytic enzymes and expose an egg-binding protein. Because NAADP (nicotinic acid adenine dinucleotide phosphate) releases Ca2+ from acidic lysosome-related organelles in other cell types, we investigated a possible role for NAADP in mediating the acrosome reaction. We report that NAADP binds with high affinity to permeabilized sea urchin sperm. Moreover, we used Mn2+ quenching of luminal fura-2 and 45Ca2+ to directly demonstrate NAADP regulation of a cation channel on the acrosome. Additionally, we show that NAADP synthesis occurs through base exchange and is driven by an increase in Ca2+. We propose a new model for acrosome reaction signaling in which Ca2+ influx initiated by egg jelly stimulates NAADP synthesis and that this NAADP acts on its receptor/channel on the acrosome to release Ca2+ to drive acrosomal exocytosis.
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Affiliation(s)
- Sridhar R Vasudevan
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford OX1 3QT, United Kingdom
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8
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Coward K, Owen H, Tunwell R, Swann K, Parrington J. Phospholipid binding properties and functional characterization of a sea urchin phospholipase Cdelta in urchin and mouse eggs. Biochem Biophys Res Commun 2007; 357:964-70. [PMID: 17466265 DOI: 10.1016/j.bbrc.2007.04.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Accepted: 04/07/2007] [Indexed: 12/12/2022]
Abstract
We recently identified a novel phospholipase Cdelta isoform, PLC-deltasu, in sea urchin gametes, whose precise functional role during fertilization and early embryogenesis remains unknown. Here, we characterized the binding of the PLC-deltasu PH domain to different phosphatidylinositol (PI) phospholipids and studied changes in its localization during fertilization. The PLC-deltasu PH domain bound most strongly to PI(3,4)P(2) and PI(3,5)P(2) phospholipids, in contrast to the PLCdelta1 PH domain which bound predominantly to PI(4,5)P(2). A green fluorescent protein tagged PLC-deltasu PH domain localized to the plasma membrane and its localization increased at fertilization and following addition of a Ca(2+) ionophore. However, recombinant PLC-deltasu failed to cause Ca(2+) signals like those seen at fertilization, in mouse and sea urchin eggs. Our findings suggest that PLC-deltasu is unlikely to be directly involved in the process of egg activation but may play a role in mediating extracellular signals transmitted via the PI 3'-kinase pathway.
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Affiliation(s)
- Kevin Coward
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
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9
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Beltrán C, Galindo BE, Rodríguez-Miranda E, Sánchez D. Signal transduction mechanisms regulating ion fluxes in the sea urchin sperm. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/sita.200600129] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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10
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Roux MM, Townley IK, Raisch M, Reade A, Bradham C, Humphreys G, Gunaratne HJ, Killian CE, Moy G, Su YH, Ettensohn CA, Wilt F, Vacquier VD, Burke RD, Wessel G, Foltz KR. A functional genomic and proteomic perspective of sea urchin calcium signaling and egg activation. Dev Biol 2006; 300:416-33. [PMID: 17054939 DOI: 10.1016/j.ydbio.2006.09.006] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Revised: 09/01/2006] [Accepted: 09/02/2006] [Indexed: 01/02/2023]
Abstract
The sea urchin egg has a rich history of contributions to our understanding of fundamental questions of egg activation at fertilization. Within seconds of sperm-egg interaction, calcium is released from the egg endoplasmic reticulum, launching the zygote into the mitotic cell cycle and the developmental program. The sequence of the Strongylocentrotus purpuratus genome offers unique opportunities to apply functional genomic and proteomic approaches to investigate the repertoire and regulation of Ca(2+) signaling and homeostasis modules present in the egg and zygote. The sea urchin "calcium toolkit" as predicted by the genome is described. Emphasis is on the Ca(2+) signaling modules operating during egg activation, but the Ca(2+) signaling repertoire has ramifications for later developmental events and adult physiology as well. Presented here are the mechanisms that control the initial release of Ca(2+) at fertilization and additional signaling components predicted by the genome and found to be expressed and operating in eggs at fertilization. The initial release of Ca(2+) serves to coordinate egg activation, which is largely a phenomenon of post-translational modifications, especially dynamic protein phosphorylation. Functional proteomics can now be used to identify the phosphoproteome in general and specific kinase targets in particular. This approach is described along with findings to date. Key outstanding questions regarding the activation of the developmental program are framed in the context of what has been learned from the genome and how this knowledge can be applied to functional studies.
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Affiliation(s)
- Michelle M Roux
- Department MCD Biology and Marine Science Institute, University of California, Santa Barbara, CA 93106-9610, USA
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Kulisz A, Dowal L, Scarlata S, Shen SS. Cloning and characterization of a phospholipase C-beta isoform from the sea urchin Lytechinus pictus. Dev Growth Differ 2005; 47:307-21. [PMID: 16026539 DOI: 10.1111/j.1440-169x.2005.00806.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Calcium is a ubiquitous intracellular signaling molecule controlling a wide array of cellular processes including fertilization and egg activation. The mechanism for triggering intracellular Ca(2+) release in sea urchin eggs during fertilization is the generation of inositol-1,4,5-trisphosphate by phospholipase C (PLC) hydrolysis of phosphatidylinositol-4,5-bisphosphate. Of the five PLC isoforms identified in mammals (beta, gamma, delta, epsilon and zeta), only PLCgamma and PLCdelta have been detected in echinoderms. Here, we provide direct evidence of the presence of a PLCbeta isoform, named suPLCbeta, within sea urchin eggs. The coding sequence was cloned from eggs of Lytechinus pictus and determined to have the greatest degree of homology and identity with the mammalian PLCbeta4. The presence of suPLCbeta within the egg was verified using a specifically generated antibody. The majority of the enzyme is localized in the non-soluble fraction, presumably the plasma membrane of the unfertilized egg. This distribution remains unchanged 1 min postfertilization. Unlike PLCbeta4, suPLCbeta is activated by G protein betagamma subunits, and this activity is Ca(2+)-dependent. In contrast to all known PLCbeta enzymes, suPLCbeta is not activated by Galphaq-GTPgammaS subunit suggesting other protein regulators may be present in sea urchin eggs.
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Affiliation(s)
- Andre Kulisz
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50011, USA
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12
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Byrne R, Barona T, Garnier M, Koster G, Katan M, Poccia D, Larijani B. Nuclear envelope assembly is promoted by phosphoinositide-specific phospholipase C with selective recruitment of phosphatidylinositol-enriched membranes. Biochem J 2005; 387:393-400. [PMID: 15554872 PMCID: PMC1134967 DOI: 10.1042/bj20040947] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2004] [Revised: 11/10/2004] [Accepted: 11/19/2004] [Indexed: 11/17/2022]
Abstract
Nuclear envelope (NE) formation in a cell-free egg extract proceeds by precursor membrane vesicle binding to chromatin in an ATP-dependent manner, followed by a GTP-induced NE assembly step. The requirement for GTP in the latter step of this process can be mimicked by addition of bacterial PI-PLC [phosphoinositide (PtdIns)-specific phospholipase C]. The NE assembly process is here dissected in relation to the requirement for endogenous phosphoinositide metabolism, employing recombinant eukaryotic PI-PLC, inhibitors and direct phospholipid analysis using ESI-MS (electrospray ionization mass spectrometry). PtdIns (phosphatidylinositol) species analysis by ESI-MS indicates that the chromatin-bound NE precursor vesicles are enriched for specific PtdIns species. Moreover, during GTP-induced precursor vesicle fusion, the membrane vesicles become partially depleted of the PtdIns 18:0/20:4 species. These data indicate that eukaryotic PI-PLC can support NE formation, and the sensitivity to exogenous recombinant PtdIns-5-phosphatases shows that the endogenous PLC hydrolyses a 5-phosphorylated species. It is shown further that the downstream target of this DAG (diacylglycerol) pathway does not involve PKC (protein kinase C) catalytic function, but is mimicked by phorbol esters, indicating a possible engagement of one of the non-PKC phorbol ester receptors. The results show that ESI-MS can be used as a sensitive means to measure the lipid composition of biological membranes and their changes during, for example, membrane fusogenic events. We have exploited this and the intervention studies to illustrate a pivotal role for PI-PLC and its product DAG in the formation of NEs.
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Key Words
- diacylglycerol
- electrospray ionization mass spectrometry
- membrane fusion
- nuclear envelope
- phosphatidylinositol
- phosphoinositide-specific phospholipase c
- atp-gs, atp-generating system
- bapta, bis-(o-aminophenoxy)ethane-n,n,n′,n′-tetra-acetic acid
- dag, 1,2-diacylglycerol
- dioc6, 3,3′-dihexyloxacarbocyanine iodide
- ptdcho, phosphatidylcholine
- dmpc, dimyristoyl-ptdcho
- ptdins, phosphatidylinositol
- dppi, dipalmitoyl-ptdins
- er, endoplasmic reticulum
- esi-ms, electrospray ionization mass spectrometry
- gap, gtpase-activating protein
- gtp[s], guanosine 5′-[γ-thio]triphosphate
- lb, lysis buffer
- mv, membrane vesicle
- ne, nuclear envelope
- pi-plc, phosphoinositide-specific phospholipase c
- pkc, protein kinase c
- snare, soluble n-ethylmaleimide-sensitive fusion protein attachment protein receptor
- sxn, nuclei preparation buffer
- syn1-5ptase, synaptojanin 1 phosphatase
- tn, tris/nacl buffer
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Affiliation(s)
- Richard D. Byrne
- *Cell Biophysics Laboratory, London Research Institute (LRI), Cancer Research UK (CR-UK), 44, Lincoln's Inn Fields, London, WC2A 3PX, U.K
| | - Teresa M. Barona
- †Department of Biology, Amherst College, Amherst, MA 01002, U.S.A
| | - Marie Garnier
- *Cell Biophysics Laboratory, London Research Institute (LRI), Cancer Research UK (CR-UK), 44, Lincoln's Inn Fields, London, WC2A 3PX, U.K
| | - Grielof Koster
- ‡Infection, Inflammation and Repair Division, University of Southampton, Southampton, SO16 6YD, U.K
| | - Matilda Katan
- §Cancer Research UK Centre for Cell and Molecular Biology, Chester Beatty Laboratories, Institute of Cancer Research (ICR), Fulham Rd, London, SW3 6JB, U.K
| | - Dominic L. Poccia
- †Department of Biology, Amherst College, Amherst, MA 01002, U.S.A
- ∥UIBD, Universidade Lusófona, Campo Grande 376, 1749–1024, Lisbon, Portugal
| | - Banafshé Larijani
- *Cell Biophysics Laboratory, London Research Institute (LRI), Cancer Research UK (CR-UK), 44, Lincoln's Inn Fields, London, WC2A 3PX, U.K
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Thaler CD, Kuo RC, Patton C, Preston CM, Yagisawa H, Epel D. Phosphoinositide metabolism at fertilization of sea urchin eggs measured with a GFP-probe. Dev Growth Differ 2005; 46:413-23. [PMID: 15606487 DOI: 10.1111/j.1440-169x.2004.00758.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Fertilization elicits a dramatic, transient rise in Ca2+ within the egg which is an essential component of egg activation and consequent initiation of development. In the sea urchin egg, three distinct Ca2+ stores have been identified which could, either individually or in combination, initiate Ca2+ release at fertilization. Inositol 1,4,5-trisphosphate (IP3) production by phospholipase C (PLC) has been suggested as the singular signal in initiating the Ca2+ transient. Other studies indicate that Ca2+ stores gated by cyclic adenosine diphosphate ribose (cADPR) or nicotinic acid adenine dinucleotide phosphate (NAADP) are also necessary. We have examined the temporal relationship between the Ca2+ rise and IP3 production at fertilization in vivo within individual eggs using a green fluorescent protein (GFP) coupled to a pleckstrin homology (PH) domain that can detect changes in IP3. Translocation of the probe occurred after the Ca2+ rise was initiated. Earlier, and possibly smaller, IP3 changes could not be excluded due to limitations in probe sensitivity. High IP3 levels are maintained during the decline in cytoplasmic Ca2+, suggesting that later IP3 metabolism might not be related to regulation of Ca2+, but may function to modulate other PIP2 regulated events such as actin polymerization or reflect other novel phosphoinositide signaling pathways.
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Affiliation(s)
- Catherine D Thaler
- Hopkins Marine Station, Stanford University, Pacific Grove, CA 93950, USA
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14
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Hwang JI, Kim HS, Lee JR, Kim E, Ryu SH, Suh PG. The Interaction of Phospholipase C-β3 with Shank2 Regulates mGluR-mediated Calcium Signal. J Biol Chem 2005; 280:12467-73. [PMID: 15632121 DOI: 10.1074/jbc.m410740200] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Phospholipase C-beta isozymes that are activated by G protein-coupled receptors (GPCR) and heterotrimeric G proteins carry a PSD-95/Dlg/ZO-1 (PDZ) domain binding motif at their C terminus. Through interactions with PDZ domains, this motif may endow the PLC-beta isozyme with specific roles in GPCR signaling events that occur in compartmentalized regions of the plasma membrane. In this study, we identified the interaction of PLC-beta3 with Shank2, a PDZ domain-containing multimodular scaffold in the postsynaptic density (PSD). The C terminus of PLC-beta3, but not other PLC-beta isotypes, specifically interacts with the PDZ domain of Shank2. Homer 1b, a Shank-interacting protein that is linked to group I metabotropic glutamate receptors and IP3 receptors, forms a multiple complex with Shank2 and PLC-beta3. Importantly, microinjection of a synthetic peptide specifically mimicking the C terminus of PLC-beta3 markedly reduces the mGluR-mediated intracellular calcium response. These results demonstrate that Shank2 brings PLC-beta3 closer to Homer 1b and constitutes an efficient mGluR-coupled signaling pathway in the PSD region of neuronal synapses.
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Affiliation(s)
- Jong-Ik Hwang
- Department of Life Science, Division of Molecular and Life Science, Pohang University of Science and Technology, Pohang 790-784, Korea
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