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Uzbekov R, Singina GN, Shedova EN, Banliat C, Avidor-Reiss T, Uzbekova S. Centrosome Formation in the Bovine Early Embryo. Cells 2023; 12:1335. [PMID: 37174735 PMCID: PMC10177215 DOI: 10.3390/cells12091335] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 04/21/2023] [Accepted: 04/30/2023] [Indexed: 05/15/2023] Open
Abstract
Centrosome formation during early development in mice and rats occurs due to the appearance of centrioles de novo. In contrast, in humans and other non-rodent mammals, centrioles are thought to be derived from spermatozoa. Ultrastructural study of zygotes and early embryos of cattle at full series of ultrathin sections show that the proximal centriole of the spermatozoon disappears by the end of the first cleavage division. Centrioles appear in two to four cell embryos in fertilized oocytes and in parthenogenetic embryos. Centriole formation includes the appearance of atypical centrioles with randomly arranged triplets and centrioles with microtubule triplets of various lengths. After the third cleavage, four centriolar cylinders appear for the first time in the blastomeres while each embryo still has two atypical centrioles. Our results showed that the mechanisms of centriole formation in different groups of mammals are universal, differing only in the stage of development in which they occur.
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Affiliation(s)
- Rustem Uzbekov
- Laboratory of Cell Biology and Electron Microscopy, Faculty of Medicine, University of Tours, 37032 Tours, France
- Faculty of Bioengineering and Bioinformatics, Moscow State University, 119992 Moscow, Russia
| | - Galina N. Singina
- Laboratory of Experimental Embryology, L.K. Ernst Federal Research Center for Animal Husbandry, Moscow Region, 142132 Podolsk, Russia
| | - Ekaterina N. Shedova
- Laboratory of Experimental Embryology, L.K. Ernst Federal Research Center for Animal Husbandry, Moscow Region, 142132 Podolsk, Russia
| | - Charles Banliat
- Ecole Supérieure d’agricultures (ESA), Unité de Recherche sur les Systèmes D’élevage (URSE), 55 rue Rabelais BP, 30748 Angers, France
| | - Tomer Avidor-Reiss
- Department of Biological Sciences, University of Toledo, Toledo, OH 43606, USA
| | - Svetlana Uzbekova
- UMR Physiologie de la Reproduction et des Comportements (PRC), INRAE, CNRS, Université de Tours, IFCE, 37380 Nouzilly, France
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Vasilev F, Limatola N, Chun JT, Santella L. Contributions of suboolemmal acidic vesicles and microvilli to the intracellular Ca 2+ increase in the sea urchin eggs at fertilization. Int J Biol Sci 2019; 15:757-775. [PMID: 30906208 PMCID: PMC6429021 DOI: 10.7150/ijbs.28461] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 12/15/2018] [Indexed: 12/03/2022] Open
Abstract
The onset of fertilization in echinoderms is characterized by instantaneous increase of Ca2+ in the egg cortex, which is called 'cortical flash', and the subsequent Ca2+ wave. While the cortical flash is due to the ion influx through L-type Ca2+ channels in starfish eggs, its amplitude was shown to be affected by the integrity of the egg cortex. Here, we investigated the contribution of cortical granules (CG) and yolk granules (YG) to the sperm-induced Ca2+ signals in sea urchin eggs. To this end, prior to fertilization, Paracentrotus lividus eggs were treated with agents that disrupt or relocate CG beneath the plasma membrane: namely, glycyl-L-phenylalanine 2-naphthylamide (GPN), procaine, urethane, and NH4Cl. All these pretreatments consistently suppressed the cortical flash in the fertilized eggs, and accelerated the decay kinetics of the subsiding Ca2+ wave in most cases. By contrast, centrifugation of the eggs, which stratifies organelles but not the CG, did not exhibit such changes except that the CF was much enhanced in the centrifugal pole where YG are localized. Surprisingly, we noted that pretreatment of the eggs with these CG-disrupting agents or with the inhibitors of L-type Ca2+ channels all drastically reduced the density of the microvilli and their individual shapes on the egg surface. Taken together, our results suggest that the integrity of the egg cortex ensures successful generation of the Ca2+ responses at fertilization, and that modulation of microvilli shape and density may serve as a mechanism of controlling ion flux across the plasma membrane.
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Affiliation(s)
- F Vasilev
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Napoli, Italy
| | - N Limatola
- Department of Research Infrastructures for Marine Biological Resources, Stazione Zoologica Anton Dohrn, Napoli, Italy
| | - J T Chun
- Department of Biology and Evolution of Marine Organisms, Stazione Zoologica Anton Dohrn, Napoli, Italy
| | - L Santella
- Department of Research Infrastructures for Marine Biological Resources, Stazione Zoologica Anton Dohrn, Napoli, Italy
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Mazzini M, Callaini G, Mencarelli C. A comparative analysis of the evolution of the egg envelopes and the origin of the yolk. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/11250008409439457] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Hülser D, Schatten G. Bioelectric responses at fertilization: Separation of the events associated with insemination from those due to the cortical reaction in sea urchin, Lytechinus variegatus. ACTA ACUST UNITED AC 2005. [DOI: 10.1002/mrd.1120050407] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Wessel GM, Brooks JM, Green E, Haley S, Voronina E, Wong J, Zaydfudim V, Conner S. The biology of cortical granules. INTERNATIONAL REVIEW OF CYTOLOGY 2002; 209:117-206. [PMID: 11580200 DOI: 10.1016/s0074-7696(01)09012-x] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
An egg-that took weeks to months to make in the adult-can be extraordinarily transformed within minutes during its fertilization. This review will focus on the molecular biology of the specialized secretory vesicles of fertilization, the cortical granules. We will discuss their role in the fertilization process, their contents, how they are made, and the molecular mechanisms that regulate their secretion at fertilization. This population of secretory vesicles has inherent interest for our understanding of the fertilization process. In addition, they have import because they enhance our understanding of the basic processes of secretory vesicle construction and regulation, since oocytes across species utilize this vesicle type. Here, we examine diverse animals in a comparative approach to help us understand how these vesicles function throughout phylogeny and to establish conserved themes of function.
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Affiliation(s)
- G M Wessel
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, Rhode Island 02912 , USA
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Berg LK, Wessel GM. Cortical granules of the sea urchin translocate early in oocyte maturation. Development 1997; 124:1845-50. [PMID: 9165131 DOI: 10.1242/dev.124.9.1845] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cortical granules are secretory vesicles poised at the cortex of an egg that, upon stimulation by sperm contact at fertilization, secrete their contents. These contents modify the extracellular environment and block additional sperm from reaching the egg. The role of cortical granules in blocking polyspermy is conserved throughout much of phylogeny. In the sea urchin, cortical granules accumulate throughout the cytoplasm during oogenesis, but in mature eggs the cortical granules are attached to the plasma membrane, having translocated to the cortex at some earlier time. To study the process of cortical granule translocation to the cell surface we have devised a procedure for maturation of sea urchin oocytes in vitro. Using this procedure, we examined the rate of oocyte maturation by observing the movement and breakdown of the germinal vesicle, the formation of polar bodies and the formation of the egg pronucleus. We find that oocyte maturation takes approximately 9 hours in the species used here (Lytechinus variegatus), from the earliest indication of maturation (germinal vesicle movement) to formation of a distinct pronucleus. We then observed the translocation of cortical granules in these cells by immunolocalization using a monoclonal antibody to hyalin, a protein packaged specifically in cortical granules. We found that the translocation of cortical granules in in vitro-matured oocytes begins with the movement of the germinal vesicle to the oocyte cell surface, and is 50% complete 1 hour after germinal vesicle breakdown. In the in vitro-matured egg, 99% of the cortical granules are at the cortex, indistinguishable from translocation in oocytes that mature in vivo. We have also found that eggs that mature in vitro are functionally identical to eggs that mature in vivo by four criteria. (1) The matured cells undergo a selective turnover of mRNA encoding cortical granule contents. (2) The newly formed pronucleus begins transcription of histone messages. (3) Cortical granules that translocate in vitro are capable of exocytosis upon activation by the calcium ionophore, A23187. (4) The mature egg is fertilizable and undergoes normal cleavage and development. In vitro oocyte maturation enables us to examine the mechanism of cortical granule translocation and other processes that had previously only been observed in static sections of fixed ovaries.
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Affiliation(s)
- L K Berg
- Department of Molecular and Cell Biology and Biochemistry, Brown University, Providence, RI 02912, USA
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7
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Abstract
Propranolol, a beta-adrenergic receptor blocker, is found to induce polyspermy in sea urchin eggs. Unfertilized sea urchin eggs treated for 10 min with 50 microM of propranolol, and then inseminated, become polyspermic and show a fertilization envelope which is barely visible to the light microscope. Examination of treated eggs by transmission and scanning electron microscopy shows that the drug does not alter the cortex of the unfertilized egg. However, after insemination an incomplete cortical reaction occurs. This might well account for both polyspermy and the defective elevation of the fertilization envelope. Since the effects of the drug are reversed by simultaneous treatment with adrenalin, perhaps propranolol interferes with the monoaminergic system that has been proposed to be active. The involvement of the monoaminergic system in the fertilization process is present in the sea urchin egg.
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Affiliation(s)
- A Nicotra
- Department of Animal and Human Biology, University of Rome, Italy
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8
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Begg DA, Wong GK, Hoyle DH, Baltz JM. Stimulation of cortical actin polymerization in the sea urchin egg cortex by NH4Cl, procaine and urethane: elevation of cytoplasmic pH is not the common mechanism of action. CELL MOTILITY AND THE CYTOSKELETON 1996; 35:210-24. [PMID: 8913642 DOI: 10.1002/(sici)1097-0169(1996)35:3<210::aid-cm4>3.0.co;2-c] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Previous studies have demonstrated that the penetrating weak base NH4Cl and the anesthetics procaine and urethane disrupt the normal attachment of cortical granules to the cortex of the sea urchin egg. Hylander and Summers (1981: Dev. Biol. 86:1-11) hypothesized that this effect may be caused by a pH-induced polymerization of cortical actin. We have tested this hypothesis by measuring the intracellular pH of eggs of the sea urchins S. purpuratus and A. punctulata treated with NH4Cl, procaine, or urethane, and determining the effects of these agents on the organization of cortical actin. Intracellular pH was determined by the ratiometric measurement of the fluorescent dye BCECF, and filamentous actin organization was examined by confocal laser scanning microscopy of BODIPY-phallocidin stained eggs. Treatment of eggs with either NH4Cl or procaine resulted in a rapid and reversible increase in cytoplasmic pH of up to 1 pH unit and a dose-dependent increase in the intensity of fluorescent staining of the cortex, indicating an increase in the content of filamentous actin. While urethane also induced a dramatic polymerization of cortical actin, no effect on cytoplasmic pH could be detected. These results demonstrate that NH4Cl, procaine and urethane all induce an increase in the amount of filamentous actin in the sea urchin egg cortex that may participate in the detachment of cortical granules. However, these compounds do not share a common mechanism of action based on the elevation of cytoplasmic pH.
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Affiliation(s)
- D A Begg
- Department of Anatomy and Cell Biology, University of Alberta, Edmonton, Canada
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9
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Longo FJ, Woerner M, Chiba K, Hoshi M. Cortical changes in starfish (Asterina pectinifera) oocytes during 1-methyladenine-induced maturation and fertilisation/activation. ZYGOTE 1995; 3:225-39. [PMID: 8903792 DOI: 10.1017/s0967199400002628] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Maturation of the starfish oocyte cortex to produce an effective cortical granule reaction and fertilisation envelope is believed to develop in three phases: (1) pre-methyladenine (1-MA) stimulation; (2) post-1-MA stimulation, pregerminal vesicle breakdown; and (3) post-germinal vesicle breakdown. The present study was initiated to identify what each of these phases may encompass, specifically with respect to structures associated with the oocyte cortex, including cortical granules, microvilli and vitelline layer. 1-MA treatment brought about an orientation of cortical granules such that they became positioned perpendicular to the oocyte surface, and an approximately 4-fold decrease in microvillar length. A-23187 activation of immature oocytes treated with (10 min; pregerminal vesicle breakdown) or without 1-MA resulted in a reduction in cortical granule number of 21% and 41%, respectively (mature oocytes underwent a 96% reduction in cortical granules). Elevation of the fertilisation envelope in both cases was significantly retarded compared with activated mature oocytes. In activated mature oocytes, the vitelline layer elevated 20.0 +/- 5.4 mu m from the egg's surface, whereas in immature oocytes treated with just A-23187 or with 1-MA (10 min) and A-23187, it lifted 0.35 +/- 0.1 and 0.17 +/- 0.04 mu m, respectively. The fertilisation envelopes of activated (or fertilised) immature oocytes also differed morphologically from those of mature oocytes. In activated, immature oocytes, the fertilisation envelope was not uniform in its thickness and possessed thick and thin regions as well as fenestrations. Additionally, it lacked a complete electron-dense stratum that characterised the fertilisation envelopes of mature oocytes. The nascent perivitelline space of immature oocytes was also distinguished by the presence of numerous vesicles which appeared to be derived from microvilli. Differences in the morphology of cortices from activated (fertilised) and non-activated, immature and mature oocytes substantiate previous investigations demonstrating three phases of cortical maturation, and are consistent with physiological changes that occur during oocyte maturation, involving ionic conductance of the plasma membrane, establishment of slow and fast blocks to polyspermy and elevation of a fertilisation envelope.
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Affiliation(s)
- F J Longo
- Department of Anatomy, University of Iowa, USA
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10
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VAN VOORHIS BRADLEYJ, SNYDER GARYD, LONGO FRANKJ. Effects of quinacrine on egg activation: A possible role for phospholipase A2in sea urchin fertilization. INVERTEBR REPROD DEV 1992. [DOI: 10.1080/07924259.1992.9672217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Sathananthan AH, Kola I, Osborne J, Trounson A, Ng SC, Bongso A, Ratnam SS. Centrioles in the beginning of human development. Proc Natl Acad Sci U S A 1991; 88:4806-10. [PMID: 2052559 PMCID: PMC51755 DOI: 10.1073/pnas.88.11.4806] [Citation(s) in RCA: 128] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
We demonstrate the presence of centrioles in fertilized human oocytes at syngamy. Single or double centrioles within centrosomes were detected by transmission electron microscopy at one pole of the first cleavage spindle in normal and dispermic embryos (25-26 hr after insemination). Sperm centrioles were also closely associated with the male pronucleus (16-20 hr after insemination) in pronuclear stage embryos. A tripolar spindle derived from a tripronuclear embryo is also demonstrated with two centrioles at one pole. The data provide evidence that human centrioles, as those in most other animals, and unlike the mouse, are paternally derived, thus supporting Boveri's classical theory. Furthermore, this study provides insights to the proposed mechanisms of aberrant cleavage patterns of dispermic human embryos.
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Affiliation(s)
- A H Sathananthan
- Centre for Early Human Development, Monash Medical Centre, Clayton, Australia
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12
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Longo FJ. Gamete interactions and the fate of sperm organelles in fertilized echinoderm eggs. JOURNAL OF ELECTRON MICROSCOPY TECHNIQUE 1991; 17:246-65. [PMID: 2045961 DOI: 10.1002/jemt.1060170303] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Investigations of gamete fusion, sperm entry and the fate of the sperm nucleus, plasma membrane, mitochondrion, and axonemal complex in fertilized echinoderm eggs are reviewed. The timing of gamete fusion with respect to the onset of electrical activity characteristic of the activated egg and the affects of fixation conditions on the stability of fusing membranes are discussed. Observations from investigations using cationized ferritin labeled gametes and immunogold cytochemistry to demonstrate the mixing of sperm plasma membrane components within the egg plasma membrane, in particular along the surface of the fertilization cone, are compared with results from studies in somatic cells. Transformations of the sperm nucleus into a male pronucleus, consisting of sperm nuclear envelope breakdown, chromatin dispersion, and formation of a pronuclear envelope, are correlated with recent biochemical observation of similar processes in other cellular systems. Fates of the sperm mitochondrion and axonemal complex are examined.
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Affiliation(s)
- F J Longo
- Department of Anatomy, University of Iowa, Iowa City 52242
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13
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Longo FJ. Reorganization of the egg surface at fertilization. INTERNATIONAL REVIEW OF CYTOLOGY 1988; 113:233-69. [PMID: 3068182 DOI: 10.1016/s0074-7696(08)60850-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- F J Longo
- Department of Anatomy, University of Iowa, Iowa City 52242
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14
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Longo FJ. Surface changes at fertilization: integration of sea urchin (Arbacia punctulata) sperm and oocyte plasma membranes. Dev Biol 1986; 116:143-59. [PMID: 3732604 DOI: 10.1016/0012-1606(86)90051-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
To examine the integration and fate of the sperm plasma membrane following its incorporation into the oocyte plasma membrane, we have fertilized sea urchin (Arbacia punctulata) gametes reciprocally labeled with cationized ferritin. When unlabeled oocytes were inseminated with labeled sperm, cationized ferritin acceptors moved laterally from the sperm plasma membrane into the fertilization cone and surrounding microvilli, mixing with components of the oocyte plasmalemma. Labeled oocytes inseminated with unlabeled sperm produced extremely large fertilization cones, completely devoid of cationized ferritin, while the remainder of the oocyte surface remained heavily labeled. Surface area measurements indicated that if all the sperm plasmalemma were utilized to delimit a fertilization cone it would provide less than 10% of the total surface membrane. Evidence is presented indicating that a principal source of membrane to the expanding fertilization cone of inseminated oocytes is from microvilli, i.e., microvilli are retracted to accommodate fertilization cone formation. Membrane delimiting the fertilization cone has a much lower affinity for agents (cationized ferritin and concanavalin A) that stain negatively charged and carbohydrate moieties compared to other regions of the oocyte surface. These ultrastructural observations indicate that significant rearrangements occur in the oocyte and sperm plasma membranes following gamete fusion which give rise to asymmetries in membrane topography; components of both membranes are redistributed within the bilayer adjacent to and delimiting the fertilization cone.
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de Freitas JC, Sawaya MI. Anomalies in sea-urchin egg development induced by a novel purine isolated from the sea-anemone Bunodosoma caissarum. Toxicon 1986; 24:751-5. [PMID: 2877513 DOI: 10.1016/0041-0101(86)90099-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Caissarone (mol. wt 229.5; melting point 285-290 degrees C) is a novel purine isolated and purified from the sea-anemone Bunodosoma caissarum. The purine inhibits the detachment of the vitelline layer from the sea-urchin egg plasma membrane after fertilization and this effect leads to polyspermy. Various abnormalities were detected at various embryonic stages, from multipolar egg division through unequal cleavages and exogastrulation up to teratogenic effects on the sea-urchin larvae (echinopluteus).
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17
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Fisher GW, Summers RG, Rebhun LI. Analysis of sea urchin egg cortical transformation in the absence of cortical granule exocytosis. Dev Biol 1985; 109:489-503. [PMID: 4039691 DOI: 10.1016/0012-1606(85)90474-9] [Citation(s) in RCA: 9] [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
A burst of endocytosis accompanying microvillar elongation follows cortical granule exocytosis in normal sea urchin development. By 5 min postfertilization the burst is over and a lower level of endocytosis ensues (constitutive phase). To determine whether microvillar elongation and initiation of endocytosis are necessary concommitants of cortical granule exocytosis we utilized Chase's (1967, Ph.D. thesis, University of Washington, Seattle) high-hydrostatic pressure technique to block the latter and then examined developing eggs for endocytosis and microvillar elongation. To accomplish this, eggs were fertilized, after which hydrostatic pressure was quickly raised to 6000-7000 psi at the start of cortical granule exocytosis and maintained for 5 min. Only the cortical granules immediately surrounding the sperm penetration site were secreted (about 3% or less of the egg's total number of cortical granules). Blockage of major cortical granule exocytosis had the following consequences on surface events during first division: (1) The endocytosis burst normally associated with cortical granule exocytosis was effectively eliminated as was early microvillar elongation and elevation. Both occurred to a limited extent around the sperm penetration site which resulted in a highly localized surface transformation. (2) By 20 min after fertilization endocytosis began over the rest of the egg surface in the absence of any further cortical granule exocytosis. (3) Subsequently, during a 30-min period starting midway between fertilization and first cleavage microvilli more than doubled in length and endocytosis levels increased severalfold. These events brought about a complete surface transformation similar to that which normally occurs in early development but in the absence of cortical granule exocytosis. By first cleavage surfaces and cortices of high-pressure-treated and control eggs were nearly indistinguishable except for the presence of cortical granules in cortices of the former. Pressure-treated eggs cleaved normally and developed to larval forms overnight. The period of late surface transformation in high-pressure-treated Strongylocentrotus purpuratus eggs corresponds in timing and some of its characteristics to second phase microvillar elongation observed in normal development in this species and also in S. droebachiensis development. These observations suggest, therefore, that microvillar elongation and endocytosis are necessary membrane remodelling events which must occur for normal development even in the absence of membrane addition from the cortical granules.
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Stapleton CL, Mills LL, Chandler DE. Cortical granule exocytosis in sea urchin eggs is inhibited by drugs that alter intracellular calcium stores. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1985; 234:289-99. [PMID: 3998686 DOI: 10.1002/jez.1402340215] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
In sea urchin eggs fertilization is accompanied by cortical granule exocytosis, a secretory event thought to be initiated by release of intracellularly sequestered calcium. We have examined the effect of two drugs on this process: chlortetracycline (CTC), a known chelator of intracellular calcium, and 8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate (TMB-8), an antagonist of intracellular calcium release in both skeletal and smooth muscle. Preincubation of eggs for 10 min with either CTC or TMB-8 blocked sperm entry, inhibited the burst of 45Ca2+ efflux normally seen postinsemination, and prevented fertilization envelope elevation. Half-maximal inhibition occurred with 200 microM CTC and 60 microM TMB-8. Electron microscopy confirmed that cortical granule exocytosis had been blocked, although inhibition was not due to a direct effect on exocytosis. CTC and TMB-8 had no effect on Ca2+-stimulated granule fusion in isolated egg cortices. Rather, these drugs block the early events in egg activation: sperm incorporation and triggering of exocytosis. These two effects appear to be independent since addition of either drug just before insemination permits sperm entry but inhibits calcium release and cortical granule exocytosis.
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Fisher GW, Rebhun LI. Sea urchin egg cortical granule exocytosis is followed by a burst of membrane retrieval via uptake into coated vesicles. Dev Biol 1983; 99:456-72. [PMID: 6413283 DOI: 10.1016/0012-1606(83)90295-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Using improved fixation procedures we have found that extensive endocytotic activity is turned on at fertilization in eggs of three species of sea urchins. Beginning after completion of cortical granule exocytosis and after exocytotic pits have completely smoothed over, the entire activated egg surface engages in a limited period of extensive removal of membrane via uptake into coated vesicles. This "burst phase" lasts about 3-5 min after which the number of invaginating coated vesicles decreases rapidly. At the end of this burst phase all the patches of cortical granule membranes have disappeared, and the egg surface is left uniformly covered by microvilli. For the remainder of the first cell cycle coated pits continue to form at a slower but steady rate. Endocytotic activity continues past the time of first cleavage. There is distinct overlap in onset and duration of the burst phase of endocytosis with the period of medium acidification during normal development. However, activation of eggs in choline sea water, which inhibits acid secretion, results in an endocytic burst whose timing and duration are similar to those in normal eggs. The endocytic burst is, therefore, independent of cytoplasmic alkalinization. These results suggest, in accord with the two-step model of egg activation (D. Epel, R. A. Steinhardt, and R. A. Humphreys, 1974; Dev. Biol. 40, 245-255; D. Epel, 1978, Curr. Top. Dev. Biol. 12, 185-246) that initiation of endocytosis is most likely a Ca2+-dependent event.
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20
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Schmidt T, Epel D. High hydrostatic pressure and the dissection of fertilization responses. I. The relationship between cortical granule exocytosis and proton efflux during fertilization of the sea urchin egg. Exp Cell Res 1983; 146:235-48. [PMID: 6307729 DOI: 10.1016/0014-4827(83)90126-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
High hydrostatic pressure applied between sperm attachment and the onset of cortical granule exocytosis will inhibit this exocytotic event in sea urchin eggs. Such pressure-treated zygotes, nevertheless, are activated and capable of development. Thus, this technique can be used as a tool to study the relationship between cortical granule breakdown and other fertilization-related responses. We have studied whether the exocytosis of cortical granules is necessary for proton efflux (acid release) to occur. Our results indicate that although Ca2+ is released while the eggs are under pressure (a prerequisite for the following events to take place), cortical granule exocytosis and acid release are pressure-sensitive and completely inhibited at pressures above 400 atm (6000 psi) and 275 atm (4000 psi), respectively. However, upon decompression, acid release is initiated which amounts to 65-70% of that seen in the unpressurized controls, suggesting that the efflux mechanism does not require cortical granule exocytosis and must result from some modification of the original plasma membrane of the egg. The remaining 30-35% of the acid release is related to cortical granule exocytosis, since it can be obtained upon induction of the cortical granule fusion 30 min later under atmospheric pressure. The initiation of acid release after decompression indicates that the efflux mechanism is not transiently turned on at fertilization, but undergoing long-term modification; the recovery of the ability to induce cortical granule fusion after fertilization under pressure suggests a refilling of cytoplasmic Ca2+ stores within this time course.
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Kallenbach RJ, Paweletz N, Finze EM. Distinctive subcellular alterations induced by hypertonic stress in sea urchin eggs. Cell Calcium 1983; 4:13-26. [PMID: 6682711 DOI: 10.1016/0143-4160(83)90045-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Sea urchin eggs continuously exposed to a hypertonic solution were ultrastructurally examined for osmotic-stress induced alterations. No fertilization membranes formed during the treatment and the surface-cortex complexes remained unaltered from the unfertilized state. However, the osmotic stress did induce a number of subcellular changes. During the first 30 minutes of the treatment the eggs formed many endoplasmic reticulum whorls and compacted Golgi body aggregations. Both of these new formations can be correlated with rapid changes in intracellular calcium, known to occur in hypertonic stressed eggs. Aggregations of mitochondria could be observed at later stages; these aggregations can also be related to subcellular stress and possible changes in internal calcium concentrations. The various morphological transitions within the cytoplasm, along with the lack of a cortical reaction in these eggs, not only supports the idea that calcium is released during parthenogenetic activation, but also suggests that this free calcium originates from stores other than the stores that are involved during fertilization or simple artificial activation.
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Abstract
Developing cells have constantly to make decisions: when to proliferate and divide, when and how to differentiate. It is an increasingly attractive idea that these decisions involve changes in intracellular cation concentrations. Our ideas about the mechanisms of changes in intracellular cations come largely from the application of biophysical techniques in the study of excitable tissues. These ideas are proving very valuable to the investigation of the control of proliferation and cell development and it is evident that the ionic mechanisms which pertain in nerve and muscle have their counterparts in other cells. Just as alterations in intracellular ion concentrations serve a signalling function in excitable tissue, so too they act as signals during development. Since almost all the quantitative data on the ionic mechanisms of fertilization come from work on sea urchins we have confined our review to sea urchin eggs.
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Guraya SS. Recent progress in the structure, origin, composition, and function of cortical granules in animal egg. INTERNATIONAL REVIEW OF CYTOLOGY 1982; 78:257-360. [PMID: 6216222 DOI: 10.1016/s0074-7696(08)60108-4] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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24
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Hylander BL, Summers RG. The effect of local anesthetics and ammonia on cortical granule-plasma membrane attachment in the sea urchin egg. Dev Biol 1981; 86:1-11. [PMID: 7197237 DOI: 10.1016/0012-1606(81)90309-2] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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25
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Longo FJ. Morphological features of the surface of the sea urchin (Arbacia punctulata) egg: oolemma-cortical granule association. Dev Biol 1981; 84:173-82. [PMID: 7195846 DOI: 10.1016/0012-1606(81)90381-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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26
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Finkel T, Levitan H, Carroll EJ. Fertilization in the sea urchin arbacia punctulata inhibited by fluorescein dyes: Evidence for a plasma membrane mechanism. ACTA ACUST UNITED AC 1981. [DOI: 10.1002/mrd.1120040306] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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27
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McBlaine PJ, Carroll EJ. Sea urchin egg hyaline layer: evidence for the localization of hyalin on the unfertilized egg surface. Dev Biol 1980; 75:137-47. [PMID: 6154621 DOI: 10.1016/0012-1606(80)90150-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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28
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Shapiro BM, Eddy EM. When sperm meets egg: biochemical mechanisms of gamete interaction. INTERNATIONAL REVIEW OF CYTOLOGY 1980; 66:257-302. [PMID: 6993410 DOI: 10.1016/s0074-7696(08)61976-2] [Citation(s) in RCA: 79] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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29
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Hollinger TG, Dumont JN, Wallace RA. Calcium-induced dehiscence of cortical granules in Xenopus laevis oocytes. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1979; 210:107-15. [PMID: 536708 DOI: 10.1002/jez.1402100111] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Microinjection of 0.1 microgram of Ca++ into Xenopus laevis oocytes induces breakdown of the cortical granules. The cortical granules disappeared in both full grown (Stage VI) and small growing (Stage IV) oocytes. Microinjection of Mg++, K+, or Na+ had no effect on cortical granules in either Stage IV or Stage VI oocytes. Small quantities (0.03 microgram) of Ca++ induced dehiscence of the cortical granules only in proximity to the injection site.
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Kunkle M, Longo FJ, Magun BE. Nuclear protein changes in the maternally and paternally derived chromatin at fertilization. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1978; 203:371-80. [PMID: 641478 DOI: 10.1002/jez.1402030305] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The proteins which become associated with the paternally derived chromatin during fertilization may be instrumental in its activation and in the dramatic structural metamorphosis of the sperm nucleus during pronuclear development. Proteins associated with sperm and zygote nuclei and male and female pronuclei of fertilized sea urchin eggs were analysed by polyacrylamide gel electrophoresis in order to examine nuclear protein changes in the paternally and maternally derived chromatin following insemination. Results demonstrate major changes in both the solubility characteristics and polypeptide profiles of sperm nuclei upon insemination. Evidence is presented which indicates that at fertilization the paternally derived chromatin acquires proteins of molecular weights greater than 80,000 and a nuclear protein composition similar to that of the female pronucleus. The nuclear proteins associated with zygote nuclei were compared to those of combined male and female pronuclei and showed many similarities and some differences. Several polypeptides were present in zygote nuclei which were not observed in pronuclear extracts.
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Schuel H. Secretory functions of egg cortical granules in fertilization and development: A critical review. ACTA ACUST UNITED AC 1978. [DOI: 10.1002/mrd.1120010311] [Citation(s) in RCA: 171] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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33
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Picheral B. [Fertilization in the newt Pleurodeles. II. Penetration of the spermatozoa and the local reaction of the egg]. JOURNAL OF ULTRASTRUCTURE RESEARCH 1977; 60:181-202. [PMID: 560493 DOI: 10.1016/s0022-5320(77)80064-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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34
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Abstract
Insemination of sea urchin (Arbacia) ova with mussel (Mytilus) sperm has been accomplished by treating eggs with trypsin and suspending the gametes in seawater made alkaline with NaOH. Not all inseminated eggs undergo a cortical granule reaction. Some eggs either elevate what remains of their vitelline layer or demonstrate no cortical modification whatsoever. After its incorporation into the egg, the nucleus of Mytilus sperm undergoes changes which eventually give rise to the formation of a male pronucleus. Concomitant with these transformations, a sperm aster may develop in association with the centrioles brought into the egg with the spermatozoon. Both the male pronucleus and the sperm aster may then migrate centrad to the female pronucleus. Evidence is presented which suggests that fusion of the male pronuclei from Mytilus sperm with female pronuclei from Arbacia eggs may occur, although this was not directly observed. These results demonstrate that Mytilus sperm nuclei are able to react to conditions within Arbacia eggs and differentiate into male pronuclei.
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Abstract
Changes in the topography of the sea urchin egg after fertilization were studied by scanning and transmission electron microscopy. Strongylocentrotus purpuratus eggs were treated with dithiothreitol to modify the vitelline layer and to prevent formation of a fertilization membrane. Dithiothreitol treatment caused the microvilli to become more irregular in shape, length, and diameter than those of untreated eggs. The microvilli were similarly modified by trypsin treatment. This effect did not appear to be due to disruption of cytoskeletal elements beneath the plasma membrane, for neither colchicine nor cytochalasin B altered microvillar morphology. Thus, it appears that the vitelline layer may act in the maintenance of surface form of unfertilized eggs. Since dithiothreitol-treated eggs did not elevate a fertilization membrane, scanning electron microscopy could be used to directly observe modifications in the egg plasma membrane after fertilization. The wave of cortical granule exocytosis initiated at the point of attachment of the fertilizing sperm was characterized by the appearance of pits that subsequently opened, releasing the cortical granule contents and leaving depressions upon the egg surface. The perigranular membranes inserted during exocytosis were seen as smooth patches between the microvillous patches remaining from the original egg surface. This produced a mosaic surface with more than double the amount of membrane of unfertilized eggs. The mosaic surface subsequently reorganized to accommodate the inserted membrane material by elongation of microvilli. Blebs and membranous whorls present before reorganization suggested the existence of an unstable intermediate state of plasma membrane reorganization. Exocytosis and mosaic membrane formation were not blocked by colchicine or cytochalasin B, but microvillar elongation was blocked by cytochalasin B treatment.
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Johnson JD, Epel D. Relationship between release of surface proteins and metabolic activation of sea urchin eggs at fertilization. Proc Natl Acad Sci U S A 1975; 72:4474-8. [PMID: 1060128 PMCID: PMC388744 DOI: 10.1073/pnas.72.11.4474] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Macromolecular components are released from sea urchin eggs when their metabolism is activated at fertilization or by incubation in ammonia. When the released material is dialyzed, concentrated, and added back to partially activated eggs the rate of protein synthesis is suppressed to the level of the unactivated egg. The surface proteins of the unfertilized eggs can be labeled with 125I by a lactoperoxidase procedure. When fertilized or activated with various parthenogenetic agents, 15-25% of the total labeled protein is released; most of the label is associated with a 150,000-dalton glycoprotein. The extent of metabolic activation, as assessed by measuring increased protein synthesis, is correlated with the amount of surface label released. Several other proteins are released during activation but are not labeled by the lactoperoxidase procedure in the intact cell. We have not yet identified which of these components is responsible for suppressing protein synthesis, nor do we know if any of the other metabolic changes of fertilization such as K+ conductance and DNA synthesis are also suppressed. We suggest that these released components are surface molecules involved in maintaining the low metabolic state occurring at the end of oogenesis and that removal of these components during fertilization results in the release of the suppression of the egg.
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Anderson WA, Perotti ME. An ultracytochemical study of the respiratory potency, integrity, and fate of the sea urchin sperm mitochondria during early embryogenesis. J Biophys Biochem Cytol 1975; 66:367-76. [PMID: 167033 PMCID: PMC2109564 DOI: 10.1083/jcb.66.2.367] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Cytochrome oxidase activity via cytochrome c, as demonstrated by the diaminobenzidine procedure, has been employed in this electron microscope cytochemical study to determine the respiratory potency, integrity and fate of the Arbacia sperm mitochondrion at fertilization and during early embryogenesis. The sperm mitochondrion remained intact and was intensely positive for cytochrome oxidase activity both during and after penetration into the egg. The mitochondrion remained highly reactive throughout zygote formation, up to the eight-cell stage. The sperm mitochondrion formed many projections and buds in the cytoplasm of immature oocytes, monospermic and polyspermic eggs, and in blastomeres. At all stages of early embryogenesis, close juxtaposition and structural contact were observed between the highly reactive sperm mitochondrion and the less reactive egg mitochondria. The results suggest that following fertilization the mitochondrion of the sea urchin spermatozoon retains some degree of metabolic autonomy within the ooplasm. The structural integrity of the paternal mitochondrion is maintained along with a functional respiratory enzyme system (cytochrome c-a3). The hypothesis that the fertilizing sperm mitochondrion may have some relevance to sea urchin development is discussed.
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Longo FJ. Ultrastructural analysis of artificially activated rabbit eggs. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1975; 192:87-111. [PMID: 1127413 DOI: 10.1002/jez.1401920111] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Ultrastructural investigations have been carried out on parthenogenetic rabbit eggs in an effort to elucidate events occurring during artificial activation and their similarity to processes of fertilization and embryogenesis. Rabbit eggs were artificially activated by culturing at 10 degrees C for 24 hours followed by incubation at 37 degrees C for 2 to 24 hours. Examination of eggs immediately after incubation at 10 degrees C for 24 hours indicates that activation is initiated when the chromosomes coalesce to form a reticulum which is either surrounded completely by two parallel membranes or incompletely by cisternae of smooth endoplasmic reticulum. Aggregation of the chromosomes occurs as a result of a reduction in the number of microtubules making up the meiotic spindle. When cold treated ova are subsequently incubated at 37 degrees C a nucleus is formed which moves central where it may participate in the cleavage of the egg. Formation of a second polar body and release of the contents of the cortical granules as reported for inseminated eggs was not found to be a part of activation of the egg by cold treatment. Approximately 95% of the ova cultured at 10 degrees C for 24 hours followed by 37 degrees C for 12 hours were activated, i.e., they possessed a nucleus or they had cleaved. Many of the activated eggs cultured for short periods at 37 degrees C were structurally similar to fertilized ova, with further incubation fragmented eggs and abnormal multicellular stages predominated.
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Longo FJ, Schuel H. An ultrastructural examination of polyspermy induced by soybean trypsin inhibitor in the sea urchin Arbacia punctulata. Dev Biol 1973; 34:187-99. [PMID: 4799476 DOI: 10.1016/0012-1606(73)90349-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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43
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Schuel H, Wilson WL, Chen K, Lorand L. A trypsin-like proteinase localized in cortical granules isolated from unfertilized sea urchin eggs by zonal centrifugation. Role of the enzyme in fertilization. Dev Biol 1973; 34:175-86. [PMID: 4789438 DOI: 10.1016/0012-1606(73)90348-5] [Citation(s) in RCA: 94] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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44
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Longo FJ. An ultrastructural analysis of polyspermy in the surf clam, Spisula solidissima. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1973; 183:153-80. [PMID: 4686191 DOI: 10.1002/jez.1401830204] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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45
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Longo FJ, Plunkett W. The onset of DNA synthesis and its relation to morphogenetic events of the pronuclei in activated eggs of the sea urchin, Arbacia punctulata. Dev Biol 1973; 30:56-67. [PMID: 4735369 DOI: 10.1016/0012-1606(73)90048-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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46
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Longo FJ. An ultrastructural analysis of mitosis and cytokinesis in the zygote of the sea urchin, Arbacia punctulata. J Morphol 1972; 138:207-38. [PMID: 4672959 DOI: 10.1002/jmor.1051380206] [Citation(s) in RCA: 44] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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