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Wozniak KL, Bainbridge RE, Summerville DW, Tembo M, Phelps WA, Sauer ML, Wisner BW, Czekalski ME, Pasumarthy S, Hanson ML, Linderman MB, Luu CH, Boehm ME, Sanders SM, Buckley KM, Bain DJ, Nicotra ML, Lee MT, Carlson AE. Zinc protection of fertilized eggs is an ancient feature of sexual reproduction in animals. PLoS Biol 2020; 18:e3000811. [PMID: 32735558 PMCID: PMC7423145 DOI: 10.1371/journal.pbio.3000811] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 08/12/2020] [Accepted: 07/10/2020] [Indexed: 01/04/2023] Open
Abstract
One of the earliest and most prevalent barriers to successful reproduction is polyspermy, or fertilization of an egg by multiple sperm. To prevent these supernumerary fertilizations, eggs have evolved multiple mechanisms. It has recently been proposed that zinc released by mammalian eggs at fertilization may block additional sperm from entering. Here, we demonstrate that eggs from amphibia and teleost fish also release zinc. Using Xenopus laevis as a model, we document that zinc reversibly blocks fertilization. Finally, we demonstrate that extracellular zinc similarly disrupts early embryonic development in eggs from diverse phyla, including Cnidaria, Echinodermata, and Chordata. Our study reveals that a fundamental strategy protecting human eggs from fertilization by multiple sperm may have evolved more than 650 million years ago.
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Affiliation(s)
- Katherine L. Wozniak
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Rachel E. Bainbridge
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Dominique W. Summerville
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Maiwase Tembo
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Wesley A. Phelps
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Monica L. Sauer
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Bennett W. Wisner
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Madelyn E. Czekalski
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Srikavya Pasumarthy
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Meghan L. Hanson
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Melania B. Linderman
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Catherine H. Luu
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Madison E. Boehm
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Steven M. Sanders
- Department of Surgery and Immunology, Thomas E. Starzl Transplantation Institute, and Center for Evolutionary Biology and Medicine, University of Pittsburgh School of Medicine, Pittsburgh Pennsylvania, United States of America
| | - Katherine M. Buckley
- Department of Biological Sciences, Auburn University, Auburn, Alabama, United States of America
| | - Daniel J. Bain
- Department of Geology and Environmental Science, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Matthew L. Nicotra
- Department of Surgery and Immunology, Thomas E. Starzl Transplantation Institute, and Center for Evolutionary Biology and Medicine, University of Pittsburgh School of Medicine, Pittsburgh Pennsylvania, United States of America
| | - Miler T. Lee
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Anne E. Carlson
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
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2
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Yang S, Huang W, Guo W, Chen X, Fan B, Meng Z. Effects of gametes post-activation, egg storage and sperm-egg ratio on in vitro fertilization outcomes in the brown-marbled grouper (Epinephelus fuscoguttatus). Anim Reprod Sci 2020; 219:106529. [PMID: 32828403 DOI: 10.1016/j.anireprosci.2020.106529] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 06/08/2020] [Accepted: 06/09/2020] [Indexed: 01/20/2023]
Abstract
Due to some biological characteristics of the brown-marbled grouper, there are challenges in aquaculture enterprises focused on production of this fish. With the aim of facilitating captive breeding in brown-marbled grouper, effects on gamete post-activation, post-stripping egg storage and sperm to egg ratio on fertilization success were investigated. Results indicated eggs were fertile for 4 min after placement in seawater, thereafter, there was a reduction in fertilization. Initial curvilinear velocity (VCL) and total motility of fresh sperm was 129.3 ± 3.7 μm/s and 92.9 ± 2.4 %, both of which decreased as time elapsed post-activation, however, there was no significant difference in fertilization until 6 min post-activation of sperm. Compared with fertilization and hatching rates in eggs used immediately after collection (95.0 ± 2.8 % and 90.1 ± 4.2 %), in vitro storage of eggs had no detectable effect on fertilized egg and hatching rates until 60 min post-stripping (92.0 ± 2.8 % and 89.9 ± 2.7 %), indicating that immediate use of brown-marbled grouper eggs for fertilization is not necessary in aquaculture hatcheries. With regard to optimizing the sperm to egg ratio, there was acceptable fertilization with ratios ranging from 103 to 107, whereas there was a marked decrease in fertilization rate when there were lesser sperm concentrations. When the combined results from this study are considered, there could be improvements of artificial fertilization efficiency in the brown-marbled grouper with utilization of these findings in aquaculture enterprises focused on production of this fish.
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Affiliation(s)
- Sen Yang
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China; College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510000, China
| | - Wenhua Huang
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Wenjie Guo
- College of Animal Science and Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510000, China
| | - Xinghan Chen
- Department of Food and Environmental Engineering, Yangjiang Polytechnic, Yangjiang, Guangdong 529500, China
| | - Bin Fan
- Department of Food and Environmental Engineering, Yangjiang Polytechnic, Yangjiang, Guangdong 529500, China
| | - Zining Meng
- State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Province Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China; Southern Laboratory of Ocean Science and Engineering, Zhuhai 519000, China.
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3
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Watabe M, Izaki K, Fujino S, Maruyama M, Kojima C, Hiraiwa A, Ueno S, Iwao Y. The electrical block to polyspermy induced by an intracellular Ca
2+
increase at fertilization of the clawed frogs,
Xenopus laevis
and
Xenopus tropicalis. Mol Reprod Dev 2019; 86:387-403. [DOI: 10.1002/mrd.23115] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 12/26/2018] [Accepted: 01/09/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Mami Watabe
- Laboratory of Reproductive Developmental BiologyGraduate School of Sciences and Technology for Innovation, Yamaguchi University Yamaguchi Japan
| | - Kenta Izaki
- Laboratory of Reproductive Developmental BiologyGraduate School of Sciences and Technology for Innovation, Yamaguchi University Yamaguchi Japan
| | - Shohei Fujino
- Laboratory of Reproductive Developmental BiologyGraduate School of Sciences and Technology for Innovation, Yamaguchi University Yamaguchi Japan
| | - Mei Maruyama
- Laboratory of Reproductive Developmental BiologyGraduate School of Sciences and Technology for Innovation, Yamaguchi University Yamaguchi Japan
| | - Chiho Kojima
- Laboratory of Reproductive Developmental BiologyGraduate School of Sciences and Technology for Innovation, Yamaguchi University Yamaguchi Japan
| | - Azusa Hiraiwa
- Laboratory of Reproductive Developmental BiologyGraduate School of Sciences and Technology for Innovation, Yamaguchi University Yamaguchi Japan
| | - Shuichi Ueno
- Laboratory of Reproductive Developmental BiologyGraduate School of Sciences and Technology for Innovation, Yamaguchi University Yamaguchi Japan
| | - Yasuhiro Iwao
- Laboratory of Reproductive Developmental BiologyGraduate School of Sciences and Technology for Innovation, Yamaguchi University Yamaguchi Japan
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4
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Universality and Diversity of a Fast, Electrical Block to Polyspermy During Fertilization in Animals. DIVERSITY AND COMMONALITY IN ANIMALS 2018. [DOI: 10.1007/978-4-431-56609-0_24] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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5
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Huang X, Huan P, Liu B. A comparative proteomic analysis reveals important proteins for the fertilization and early embryonic development of the oyster Crassostrea gigas. Proteomics 2017; 17. [PMID: 27880033 DOI: 10.1002/pmic.201600251] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Revised: 11/13/2016] [Accepted: 11/15/2016] [Indexed: 11/06/2022]
Abstract
Molluscan development involves important features that are important to understanding not only molluscan ontogeny but also animal evolution. To gain insight into the gamete proteome and protein function in fertilization and early development, we analyzed the proteomes of unfertilized oocytes and early embryos (2/4-cell stage) of the Pacific oyster, Crassostrea gigas. An oocyte reference map containing 116 protein spots, of which 69 were identified, revealed a high abundance of vitellogenin-derived protein spots. The differentially regulated protein spots during fertilization were screened using comparative proteomic approaches. In total, 18 differentially regulated protein spots were screened, and 15 of these were identified and divided into three groups. The proteins belonging to the first group function in energy supply and antioxidation and are proposed to ensure successful fertilization by regulating the levels of adenosine triphosphate, resisting oxidative stress, and preventing polyspermy. The proteins of the second group are associated with protein synthesis and modification, reflecting active protein synthesis after fertilization. The three proteins belonging to the final group are hypothesized to function in the regulation of embryonic development through the establishment of cell polarity and modulation of methylation reactions in nuclei. These results will enhance our knowledge of molluscan fertilization and development.
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Affiliation(s)
- Xiaohong Huang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, P. R. China.,University of Chinese Academy of Sciences, Beijing, P. R. China
| | - Pin Huan
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, P. R. China
| | - Baozhong Liu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, P. R. China.,Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, P. R. China
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Nemova NN, Kyaivyaryainen EI, Krupnova MY. Dynamics of activity of intracellular cysteine-dependent proteases and some peptidases in embryogenesis of Atlantic salmon Salmo salar L. Russ J Dev Biol 2017. [DOI: 10.1134/s1062360417040075] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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8
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Abstract
Compared with the animal kingdom, fertilization is particularly complex in flowering plants (angiosperms). Sperm cells of angiosperms have lost their motility and require transportation as a passive cargo by the pollen tube cell to the egg apparatus (egg cell and accessory synergid cells). Sperm cell release from the pollen tube occurs after intensive communication between the pollen tube cell and the receptive synergid, culminating in the lysis of both interaction partners. Following release of the two sperm cells, they interact and fuse with two dimorphic female gametes (the egg and the central cell) forming the major seed components embryo and endosperm, respectively. This process is known as double fertilization. Here, we review the current understanding of the processes of sperm cell reception, gamete interaction, their pre-fertilization activation and fusion, as well as the mechanisms plants use to prevent the fusion of egg cells with multiple sperm cells. The role of Ca(2+) is highlighted in these various processes and comparisons are drawn between fertilization mechanisms in flowering plants and other eukaryotes, including mammals.
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Affiliation(s)
- Thomas Dresselhaus
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany.
| | - Stefanie Sprunck
- Cell Biology and Plant Biochemistry, Biochemie-Zentrum Regensburg, University of Regensburg, 93040 Regensburg, Germany
| | - Gary M Wessel
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, Rhode Island 02912, USA
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Alonso-Morales A, González-López L, Cázares-Raga FE, Cortés-Martínez L, Torres-Monzón JA, Gallegos-Pérez JL, Rodríguez MH, James AA, Hernández-Hernández FDLC. Protein phosphorylation during Plasmodium berghei gametogenesis. Exp Parasitol 2015; 156:49-60. [PMID: 26008612 DOI: 10.1016/j.exppara.2015.05.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 05/08/2015] [Accepted: 05/18/2015] [Indexed: 10/23/2022]
Abstract
Plasmodium gametogenesis within the mosquito midgut is a complex differentiation process involving signaling mediated by phosphorylation, which modulate metabolic routes and protein synthesis required to complete this development. However, the mechanisms leading to gametogenesis activation are poorly understood. We analyzed protein phosphorylation during Plasmodium berghei gametogenesis in vitro in serum-free medium using bidimensional electrophoresis (2-DE) combined with immunoblotting (IB) and antibodies specific to phosphorylated serine, threonine and tyrosine. Approximately 75 protein exhibited phosphorylation changes, of which 23 were identified by mass spectrometry. These included components of the cytoskeleton, heat shock proteins, and proteins involved in DNA synthesis and signaling pathways among others. Novel phosphorylation events support a role for these proteins during gametogenesis. The phosphorylation sites of six of the identified proteins, HSP70, WD40 repeat protein msi1, enolase, actin-1 and two isoforms of large subunit of ribonucleoside reductase were investigated using TiO2 phosphopeptides enrichment and tandem mass spectrometry. In addition, transient exposure to hydroxyurea, an inhibitor of ribonucleoside reductase, impaired male gametocytes exflagellation in a dose-dependent manner, and provides a resource for functional studies.
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Affiliation(s)
- Alberto Alonso-Morales
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Avenida Instituto Politécnico Nacional # 2508, Colonia San Pedro Zacatenco, Delegación Gustavo A. Madero, C.P. 07360, México, D.F., México
| | - Lorena González-López
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Avenida Instituto Politécnico Nacional # 2508, Colonia San Pedro Zacatenco, Delegación Gustavo A. Madero, C.P. 07360, México, D.F., México
| | - Febe Elena Cázares-Raga
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Avenida Instituto Politécnico Nacional # 2508, Colonia San Pedro Zacatenco, Delegación Gustavo A. Madero, C.P. 07360, México, D.F., México
| | - Leticia Cortés-Martínez
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Avenida Instituto Politécnico Nacional # 2508, Colonia San Pedro Zacatenco, Delegación Gustavo A. Madero, C.P. 07360, México, D.F., México
| | - Jorge Aurelio Torres-Monzón
- Centro Regional de Investigación en Salud Pública, Instituto Nacional de Salud Pública, Avenida 19 Poniente esquina 4a Norte s/n, Colonia Centro, C.P. 62100 Tapachula, Chiapas, Mexico
| | | | - Mario Henry Rodríguez
- Centro de Investigación Sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Avenida Universidad # 655, Colonia Santa María Ahuacatitlán, C.P. 62100, Cuernavaca, Morelos, México
| | - Anthony A James
- Departments of Molecular Biology and Biochemistry, and Microbiology and Molecular Genetics, University of California, Irvine, CA 92697, USA
| | - Fidel de la Cruz Hernández-Hernández
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV-IPN), Avenida Instituto Politécnico Nacional # 2508, Colonia San Pedro Zacatenco, Delegación Gustavo A. Madero, C.P. 07360, México, D.F., México.
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10
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Effects of salinity and sea salt type on egg activation, fertilization, buoyancy and early embryology of European eel, Anguilla anguilla. ZYGOTE 2015; 24:121-38. [DOI: 10.1017/s0967199414000811] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
SummaryImproper activation and swelling of in vitro produced eggs of European eel, Anguilla anguilla, has been shown to negatively affect embryonic development and hatching. We investigated this phenomenon by examining the effects of salinity and sea salt type on egg dimensions, cell cleavage patterns and egg buoyancy. Egg diameter after activation, using natural seawater adjusted to different salinities, varied among female eels, but no consistent pattern emerged. Activation salinities between 30–40 practical salinity unit (psu) produced higher quality eggs and generally larger egg diameters. Chorion diameters reached maximal values of 1642 ± 8 μm at 35 psu. A positive relationship was found between egg neutral buoyancy and activation salinity. Nine salt types were investigated as activation and incubation media. Five of these types induced a substantial perivitelline space (PVS), leading to large egg sizes, while the remaining four salt types resulted in smaller eggs. All salt types except NaCl treatments led to high fertilization rates and had no effect on fertilization success as well as egg neutral buoyancies at 7 h post-fertilization. The study points to the importance of considering ionic composition of the media when rearing fish eggs and further studies are encouraged.
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11
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Stricker SA. Calcium signaling and endoplasmic reticulum dynamics during fertilization in marine protostome worms belonging to the phylum Nemertea. Biochem Biophys Res Commun 2014; 450:1182-7. [DOI: 10.1016/j.bbrc.2014.03.156] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 03/31/2014] [Indexed: 10/25/2022]
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12
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Arakawa M, Takeda N, Tachibana K, Deguchi R. Polyspermy block in jellyfish eggs: Collaborative controls by Ca2+ and MAPK. Dev Biol 2014; 392:80-92. [DOI: 10.1016/j.ydbio.2014.04.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Revised: 03/19/2014] [Accepted: 04/25/2014] [Indexed: 11/30/2022]
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Webb SE, Miller AL. Calcium signaling in extraembryonic domains during early teleost development. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2014; 304:369-418. [PMID: 23809440 DOI: 10.1016/b978-0-12-407696-9.00007-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
It is becoming recognized that the extraembryonic domains of developing vertebrates, that is, those that make no cellular contribution to the embryo proper, act as important signaling centers that induce and pattern the germ layers and help establish the key embryonic axes. In the embryos of teleost fish, in particular, significant progress has been made in understanding how signaling activity in extraembryonic domains, such as the enveloping layer, the yolk syncytial layer, and the yolk cell, might help regulate development via a combination of inductive interactions, cellular dynamics, and localized gene expression. Ca(2+) signaling in a variety of forms that include propagating waves and standing gradients is a feature found in all three teleostean extraembryonic domains. This leads us to propose that in addition to their other well-characterized signaling activities, extraembryonic domains are well suited (due to their relative stability and continuity) to act as Ca(2+) signaling centers and conduits.
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Affiliation(s)
- Sarah E Webb
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
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14
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Kashir J, Deguchi R, Jones C, Coward K, Stricker SA. Comparative biology of sperm factors and fertilization-induced calcium signals across the animal kingdom. Mol Reprod Dev 2013; 80:787-815. [PMID: 23900730 DOI: 10.1002/mrd.22222] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Accepted: 07/23/2013] [Indexed: 11/08/2022]
Abstract
Fertilization causes mature oocytes or eggs to increase their concentrations of intracellular calcium ions (Ca²⁺) in all animals that have been examined, and such Ca²⁺ elevations, in turn, provide key activating signals that are required for non-parthenogenetic development. Several lines of evidence indicate that the Ca²⁺ transients produced during fertilization in mammals and other taxa are triggered by soluble factors that sperm deliver into oocytes after gamete fusion. Thus, for a broad-based analysis of Ca²⁺ dynamics during fertilization in animals, this article begins by summarizing data on soluble sperm factors in non-mammalian species, and subsequently reviews various topics related to a sperm-specific phospholipase C, called PLCζ, which is believed to be the predominant activator of mammalian oocytes. After characterizing initiation processes that involve sperm factors or alternative triggering mechanisms, the spatiotemporal patterns of Ca²⁺ signals in fertilized oocytes or eggs are compared in a taxon-by-taxon manner, and broadly classified as either a single major transient or a series of repetitive oscillations. Both solitary and oscillatory types of fertilization-induced Ca²⁺ signals are typically propagated as global waves that depend on Ca²⁺ release from the endoplasmic reticulum in response to increased concentrations of inositol 1,4,5-trisphosphate (IP₃). Thus, for taxa where relevant data are available, upstream pathways that elevate intraoocytic IP3 levels during fertilization are described, while other less-common modes of producing Ca²⁺ transients are also examined. In addition, the importance of fertilization-induced Ca²⁺ signals for activating development is underscored by noting some major downstream effects of these signals in various animals.
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Affiliation(s)
- Junaid Kashir
- Nuffield Department of Obstetrics and Gynaecology, University of Oxford, Level 3, Women's Centre, John Radcliffe Hospital, Headington, Oxford, UK
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