Cortical Changes in Acipenserid Eggs during Fertilization and Artificial Activation

Development ◽  
1962 ◽  
Vol 10 (1) ◽  
pp. 1-26
Author(s):  
T. A. Dettlaff
Keyword(s):  
Sea Urchins ◽  
The Other ◽  
Teleost Fishes ◽  
Perivitelline Space ◽  
Cortical Granules ◽  
Complex Chain ◽  
Artificial Activation ◽  
Suitable Object

In the complex chain of interrelated processes which make up the early changes in the egg during activation (see Tyler, 1941, 1955; Runnström, 1952; Rothschild, 1956; T. Yamamoto, 1956; Allen, 1958) many phenomena are still unclear: for example, the problem of the fertilization impulse, the rate of its spread, and its relationship with the other changes in the egg; the problem of the origin of the perivitelline space colloid and of its relation to the material of the cortical granules (Runnström, 1952; Rothschild, 1956; Allen, 1958). The main objects of investigation have hitherto been the eggs of sea urchins and, to a lesser extent, of teleost fishes, so that a danger exists that the sequence of phenomena characteristic of these eggs may be supposed to hold generally. Acipenserid eggs, because of certain peculiarities of their structure and development, are a suitable object for studies of this kind.

Silver staining of the cortical reaction in oocytes of Marthasterias glacialis (Echinodermata, Asteroidea)

1987 ◽  
Vol 65 (11) ◽  
pp. 2607-2611 ◽  
Author(s):  
Mário Sousa ◽  
Carlos Azevedo
Keyword(s):  
Silver Nitrate ◽  
Lamellar Structure ◽  
The Other ◽  
Dense Matrix ◽  
Perivitelline Space ◽  
Cortical Granules ◽  
Silver Deposits ◽  
The Matrix ◽  
Silver Nitrate Staining ◽  
Marthasterias Glacialis

Morphologically, cortical granules of the starfish Marthasterias glacialis present a lamellar structure within a dense matrix. However, with silver nitrate staining, the matrix is subdivided into argyrophilic and argyrophobic materials. Just before exocytosis the cortical granules swell. After being released in the perivitelline space, the unstained matrix disperses while the other components are incorporated into the vitelline layer. When cells are incubated with pronase before exposure to silver nitrate, no silver deposits are found.

Effects of glucuronic acid and N-acetyl-D-glucosamine supplementation on the perivitelline space during the IVM of pig oocytes

2020 ◽  
Vol 32 (10) ◽  
pp. 941
Author(s):  
J. Z. Current ◽  
B. D. Whitaker
Keyword(s):  
Hyaluronic Acid ◽  
Glutathione Peroxidase ◽  
Embryo Development ◽  
Glucuronic Acid ◽  
The Other ◽  
Perivitelline Space

The objective of this study was to minimise polyspermic penetration by increasing the perivitelline space (PVS) thickness through supplementation of the hyaluronic acid components glucuronic acid and N-acetyl-d-glucosamine (GlcNAc). Oocytes (n=4690) were supplemented during the first 24h and/or the remainder of maturation (final 16–18h) with 0.01mM glucuronic acid and 0.01mM GlcNAc and then evaluated for PVS thickness, hyaluronic acid, glutathione and glutathione peroxidase concentrations. Fertilised oocytes were evaluated for polyspermic penetration and embryo development. The PVS thickness and amount of hyaluronic acid was significantly (P<0.05) greater in oocytes supplemented with 0.01mM glucuronic acid and 0.01mM GlcNAc during the second part or all of maturation compared with the other treatments. In addition, polyspermic penetration was significantly (P<0.05) less in oocytes supplemented with 0.01mM glucuronic acid and 0.01mM GlcNAc during the second part or all of maturation compared with the other treatments. Supplementing 0.01mM glucuronic acid and GlcNAc during maturation significantly (P<0.05) increased the percentage of cleaved embryos by 48h after IVF and blastocysts formed by 144h after IVF compared those not supplemented. These results indicate that supplementing PVS components during maturation decreases polyspermic penetration by increasing PVS thickness.

scholarly journals OOCYTE DIFFERENTIATION IN THE SEA URCHIN, ARBACIA PUNCTULATA, WITH PARTICULAR REFERENCE TO THE ORIGIN OF CORTICAL GRANULES AND THEIR PARTICIPATION IN THE CORTICAL REACTION

1968 ◽  
Vol 37 (2) ◽  
pp. 514-539 ◽  
Author(s):  
Everett Anderson
Keyword(s):  
Sea Urchin ◽  
Golgi Complex ◽  
Morphological Evidence ◽  
Cortical Granule ◽  
Perivitelline Space ◽  
Unit Membrane ◽  
Cortical Granules ◽  
Arbacia Punctulata ◽  
Cortical Reaction ◽  
Oocyte Differentiation

This paper presents morphological evidence on the origin of cortical granules in the oocytes of Arbacia punctulata and other echinoderms. During oocyte differentiation, those Golgi complexes associated with the production of cortical granules are composed of numerous saccules with companion vesicles. Each element of the Golgi complex contains a rather dense homogeneous substance. The vesicular component of the Golgi complex is thought to be derived from the saccular member by a pinching-off process. The pinched-off vesicles are viewed as containers of the precursor(s) of the cortical granules. In time, they coalesce and form a mature cortical granule whose content is bounded by a unit membrane. Thus, it is asserted that the Golgi complex is involved in both the synthesis and concentration of precursors utilized in the construction of the cortical granule. Immediately after the egg is activated by the sperm the primary envelope becomes detached from the oolemma, thereby forming what we have called the activation calyx (see Discussion). Subsequent to the elaboration of the activation calyx, the contents of cortical granules are released (cortical reaction) into the perivitelline space. The discharge of the constituents of a cortical granule is accomplished by the union of its encompassing unit membrane, in several places, with the oolemma.

The appearance of glycoconjugates associated with cortical granule release during mouse fertilization

Development ◽  
1988 ◽  
Vol 102 (3) ◽  
pp. 595-604 ◽  
Author(s):  
S.H. Lee ◽  
K.K. Ahuja ◽  
D.J. Gilburt ◽  
D.G. Whittingham
Keyword(s):  
Calcium Ionophore ◽  
Calcium Ionophore A23187 ◽  
Meiotic Spindle ◽  
Cortical Granule ◽  
Ionophore A23187 ◽  
Perivitelline Space ◽  
Cell Stage ◽  
Artificial Activation ◽  
First Time ◽  
Kinetics Of

For the first time we have shown with appropriately labelled lectins that fucosyl- and sialyl-rich glycoconjugates are released into the perivitelline space of the mouse oocyte after activation by the fertilizing spermatozoon or artificial activation by the calcium ionophore A23187 or ethanol. The glycoconjugates show a punctate distribution over the oocyte surface except for the microvilli-free area overlying the second meiotic spindle from which they are absent. Their appearance in the perivitelline space is associated with the release of the cortical granule suggesting that they represent part of the cortical granule exudate. Soon after the glycoconjugates appear, they begin to aggregate. The process continues until the beginning of cytokinesis at first cleavage when a single large aggregate is found within the cleavage furrow. Most of the labelled glycoconjugates disappear by the late 2-cell stage and no evidence was found for their presence during the later preimplantation period. This technique is suitable for monitoring the kinetics of the cortical reaction in mammalian oocytes and investigating the importance of the glycoconjugates in early preimplantation period.

Cortical granule biogenesis is active throughout oogenesis in sea urchins

Development ◽  
1994 ◽  
Vol 120 (5) ◽  
pp. 1325-1333 ◽  
Author(s):  
M. Laidlaw ◽  
G.M. Wessel
Keyword(s):  
Recombinant Proteins ◽  
Sea Urchins ◽  
Germinal Vesicle ◽  
Cortical Granule ◽  
Cdna Clones ◽  
Secretory Vesicles ◽  
Cortical Granules ◽  
Oocyte Growth ◽  
Peak Abundance ◽  
Cognate Protein

Cortical granules are secretory vesicles formed in the eggs of most animals and are essential for the prevention of polyspermy in these organisms. We have studied the biogenesis of cortical granules in sea urchin oocytes by identifying cDNA clones that encode proteins targeted selectively to the cortical granules. These cDNA clones were identified by an immunoscreen of a cDNA library using antibodies to proteins of the fertilization envelope. Four different mRNAs were identified, ranging from 4 kb to 13 kb in length, that encoded proteins targeted specifically to cortical granules. Accumulation of these mRNAs began very early in oogenesis, in oocytes approximately 10–15 microns in diameter, and continued throughout oogenesis. The mRNAs reached peak abundance (on a per cell basis) in germinal vesicle stage oocytes, and the accumulation of each mRNA was linear with respect to oocyte growth. During breakdown of the germinal vesicle these mRNAs were degraded so that in eggs the mRNA signals were at background levels. Antibodies generated to recombinant proteins made from each of these cDNA clones showed that in the oocyte each cognate protein appeared early in oogenesis. These proteins accumulated only in cortical granules: no accumulation was seen in the cytoplasm, in Golgi, or in other vesicles, and no heterogeneity of the contents was seen within the population of cortical granules. Using these antibodies we show that cortical granules accumulated linearly throughout oogenesis.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Regulated Proteolysis by Cortical Granule Serine Protease 1 at Fertilization

2004 ◽  
Vol 15 (5) ◽  
pp. 2084-2092 ◽  
Author(s):  
Sheila A. Haley ◽  
Gary M. Wessel
Keyword(s):  
Serine Protease ◽  
Protease Activity ◽  
Sea Urchins ◽  
Small Population ◽  
Structural Proteins ◽  
Cortical Granule ◽  
Cortical Granules ◽  
Fluorescent Indicators ◽  
Seawater Ph ◽  
Protease Activation

Cortical granules are specialized organelles whose contents interact with the extracellular matrix of the fertilized egg to form the block to polyspermy. In sea urchins, the granule contents form a fertilization envelope (FE), and this construction is critically dependent upon protease activity. An autocatalytic serine protease, cortical granule serine protease 1 (CGSP1), has been identified in the cortical granules of Strongylocentrotus purpuratus eggs, and here we examined the regulation of the protease activity and tested potential target substrates of CGSP1. We found that CGSP1 is stored in its full-length, enzymatically quiescent form in the granule, and is inactive at pH 6.5 or below. We determined the pH of the cortical granule by fluorescent indicators and micro-pH probe measurements and found the granules to be pH 5.5, a condition inhibitory to CGSP1 activity. Exposure of the protease to the pH of seawater (pH 8.0) at exocytosis immediately activates the protease. Activation of eggs at pH 6.5 or lower blocks activation of the protease and the resultant FE phenotypes are indistinguishable from a protease-null phenotype. We find that native cortical granule targets of the protease are β-1,3 glucanase, ovoperoxidase, and the protease itself, but the structural proteins of the granule are not proteolyzed by CGSP1. Whole mount immunolocalization experiments demonstrate that inhibition of CGSP1 activity affects the localization of ovoperoxidase but does not alter targeting of structural proteins to the FE. The mistargeting of ovoperoxidase may lead to spurious peroxidative cross-linking activity and contribute to the lethality observed in protease-null cells. Thus, CGSP1 is proteolytically active only when secreted, due to the low pH of the cortical granules, and it has a small population of targets for cleavage within the cortical granules.

scholarly journals Nuclear-follower foraging associations among Characiformes fishes and Potamotrygonidae rays in clean waters environments of Teles Pires and Xingu rivers basins, Midwest Brazil

2011 ◽  
Vol 11 (4) ◽  
pp. 359-362 ◽  
Author(s):  
Domingos Garrone Neto ◽  
Lucélia Nobre Carvalho
Keyword(s):  
Freshwater Fish ◽  
The Other ◽  
Teleost Fishes ◽  
Freshwater Stingray ◽  
New Interactions ◽  
Foraging Associations ◽  
Commensal Relationship

During under and overwater observations were recorded nuclear-follower foraging associations among three species of characiform fishes - Chalceus epakros, Hemiodus semitaeniatus and Hemiodus unimaculatus - and a freshwater stingray species - Potamotrygon orbignyi - in the Teles Pires and Xingu rivers basins, Midwest Brazil. The teleost fishes were observed closely following the stingrays during the behavior of stirring the substrate to uncover invertebrates, which cause discrete sediment clouds. Apparently this sediment perturbation attracts the fishes that approached the foraging stingrays to feed on small preys and other food types exposed this way. This is a typical example of a commensal relationship in which one participant is benefited while the other is unaffected, and represents the second published record of nuclear-follower feeding association between potamotrygonid rays and teleost fishes, demonstrating the potential of naturalistic studies in discovering new interactions involving species of freshwater fish.

scholarly journals Immunoglobulin T genes in Neopterygii

2020 ◽  
Author(s):  
Serafin Mirete-Bachiller ◽  
David N. Olivieri ◽  
Francisco Gambón-Deza
Keyword(s):  
Immunoglobulin M ◽  
The Other ◽  
Teleost Fishes ◽  
Genome Sequences ◽  
Bioinformatics Pipeline ◽  
Immunoglobulin Isotypes ◽  
Depth Analysis ◽  
Learning Software ◽  
Immunoglobulin Heavy Chain Genes ◽  
Recent Duplication

AbstractIn teleost fishes there are three immunoglobulin isotypes named immunoglobulin M (IgM), D (IgD) and T (IgT). IgT has been the last to be described and is considered a teleosts-fish specific isotype. From the recent availability of genome sequences of fishes, an in-depth analysis of Actinopterygii immunoglobulin heavy chain genes was undertaken. With the aid of a bioinformatics pipeline, a machine learning software, CHfinder, was developed that identifies the coding exons of the CH domains of fish immunoglobulins. Using this pipeline, a high number of such sequences were obtained from teleosts and holostean fishes. IgT was found in teleost and holostean fishes that had not been previously described. A phylogenetic analysis reveals that IgT CH1 exons are similar to the IgM CH1. This analysis also demonstrates that the other three domains (CH2, CH3 and CH4) were not generated by recent duplication processes of IgM in Actinopterygii, indicating it is an immunoglobulin with an earlier origin.

scholarly journals Rendezvin: An Essential Gene Encoding Independent, Differentially Secreted Egg Proteins That Organize the Fertilization Envelope Proteome after Self-Association

2006 ◽  
Vol 17 (12) ◽  
pp. 5241-5252 ◽  
Author(s):  
Julian L. Wong ◽  
Gary M. Wessel
Keyword(s):  
Extracellular Matrix ◽  
Sea Urchins ◽  
Essential Gene ◽  
Cortical Granule ◽  
Cortical Granules ◽  
Gene Encoding ◽  
Self Association ◽  
Granule Secretion

Preventing polyspermy during animal fertilization relies on modifications to the egg's extracellular matrix. On fertilization in sea urchins, the contents of cortical granules are secreted and rapidly assemble into the egg's extracellular vitelline layer, forming the fertilization envelope, a proteinaceous structure that protects the zygote from subsequent sperm. Here, we document rendezvin, a gene whose transcript is differentially spliced to yield proteins destined for either cortical granules or the vitelline layer. These distinctly trafficked variants reunite after cortical granule secretion at fertilization. Together, they help coordinate assembly of the functional fertilization envelope, whose proteome is now defined in full.

scholarly journals Evolution of crabs – history and deconstruction of a prime example of convergence

2014 ◽  
Vol 83 (2) ◽  
pp. 87-105 ◽  
Author(s):  
Gerhard Scholtz
Keyword(s):  
Body Shape ◽  
Sea Urchins ◽  
The Body ◽  
External Factors ◽  
The Other ◽  
Compact Body ◽  
Body Shapes ◽  
Definition Of ◽  
Internal And External Factors

Compared with the elongate bodies of shrimps or lobsters, crabs are characterised by a compact body organisation with a depressed, short carapace and a ventrally folded pleon. The evolutionary transformation from a lobster-like crustacean towards a crab is called ‘carcinization’ and has been interpreted as a dramatic morphological change. Nevertheless, the crab-shape evolved convergently in a number of lineages within Decapoda. Accordingly, numerous hypotheses about internal and external factors have been presented, which all try to explain these frequent convergent carcinization events despite the seemingly fundamental changes in the body organisation. However, what a crab is lies greatly in the eye of the beholder and most of the hypotheses about the lobster/crab transformation are biased by untested assumptions. Furthermore, there are two meanings of the word ‘crab’ within decapods: one, the phylogenetic meaning, refers to the clade Brachyura; the other, more general and typological use of the word crab, describes decapods with a certain body shape. These two meanings should not be confused when the issue of carcinization is discussed. Here, I propose a definition of what a crab is, i.e. what is meant when we speak about carcinization. I show that not all Brachyura are crabs in the typological sense. Carcinization occurred at least twice within the clade. Among Anomala there is further evidence that crab-shaped Lithodidae derived from a hermit-crab like ancestor. Carcinization is not restricted to Anomala plus Brachyura (Meiura) but is also found in Achelata, namely in slipper lobsters. A deconstruction of the crab-shape reveals that parts of it appear in various combinations among all decapod groups. Only a certain threshold of number and quality of crab-features makes us call an animal a ‘crab’. This reveals that carcinization does not involve such dramatic changes in morphology as has been suggested. Moreover similar alterations of body shapes appear frequently in other crustacean taxa and in various animal groups as diverse as sharks and sea urchins. Hence morphological constraints, macroevolution, trends, tendencies, or underlying synapomorphies of any kind are not necessary assumptions for the explanation of the evolution of crabs.

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