Mastoparan analog to elevate fertilization membrane of sea urchin eggs

1993 ◽  
pp. 356-358
Author(s):  
Nozomi Nagano ◽  
Kazuki Saito ◽  
Masaru Toriyama ◽  
Masakatsu Imoto ◽  
Terumi Nakajima
Keyword(s):  
Sea Urchin ◽  
Sea Urchin Eggs ◽  
Fertilization Membrane

Some Experiments on Sea-urchin Eggs with Desoxynucleic Acids from Sea-urchin Sperms

Development ◽  
1953 ◽  
Vol 1 (3) ◽  
pp. 261-262
Author(s):  
Sven Hörstadius
Keyword(s):  
New York ◽  
Sea Urchin ◽  
Sea Water ◽  
Water Injection ◽  
Dark Field ◽  
The Other ◽  
Columbia University ◽  
Sea Urchin Eggs ◽  
King's College ◽  
Fertilization Membrane

Dr. I. Joan Lorch, of King's College, London, and I have made some experiments on sea-urchin eggs with desoxynucleic acids (DNA) prepared from sperms of several sea-urchin species by Professor Erwin Chargaff, of Columbia University, New York. Unfertilized eggs did not react when put into a solution of DNA in sea-water. Injection of a small amount of DNA dissolved in Callan's solution had the following consequences. If the DNA did not mix with the cytoplasm but remained as a distinct droplet, the egg could be fertilized. The droplet moved slowly towards the surface and ran out of the egg. This sometimes only occurred after several cleavages. Such eggs developed normally. If, on the other hand, the DNA mixed with the cytoplasm the egg became activated. A fertilization membrane was raised. The surface layer in dark field changed in colour from yellow to white as is the case upon fertilization.

Isolated Plasma Membranes of Sea Urchin Eggs

1971 ◽  
Vol 29 ◽  
pp. 534-535
Author(s):  
S. Inoue ◽  
E. C. Preddie ◽  
P. Guerrier
Keyword(s):  
Electron Microscope ◽  
Sea Urchin ◽  
Plasma Membranes ◽  
Membrane System ◽  
Vitelline Membrane ◽  
Thin Sections ◽  
Sea Urchin Eggs ◽  
Sea Urchin Egg ◽  
Discontinuous Sucrose Gradient ◽  
Fertilization Membrane

From electron microscope studies of thin sections the sea urchin egg is known to be surrounded by the peripheral membrane system which is made up of the outer coat (vitelline membrane), which elevates from an egg surface after fertilization and becomes a part of the fertilization membrane, and the plasma membrane. In these experiments an effort has been made to isolate plasma membranes of sea urchin eggs and these isolated membranes were observed in the electron microscope.The vitelline membrane of the eggs from the sea urchin Strongylocentrotus purpuratus was at first digested away by the treatment with 0.02% trypsin in 0.01 M Tris-HCl buffer (pH 8.0) for 5 minutes at 28°C. The plasma membranes were then isolated according to the method of Song et al. which was used for the isolation of rat liver plasma membranes. The vitelline membrane-free eggs were gently homogenized in 10-3 M NaHC03 (pH 7.5) and freed membranes were collected by centrifugation over a discontinuous sucrose gradient preparation.

scholarly journals Metabolic similarities between fertilization and phagocytosis. Conservation of a peroxidatic mechanism.

1979 ◽  
Vol 149 (4) ◽  
pp. 938-953 ◽  
Author(s):  
S J Klebanoff ◽  
C A Foerder ◽  
E M Eddy ◽  
B M Shapiro
Keyword(s):  
Sea Urchin ◽  
Polymorphonuclear Leukocytes ◽  
Cortical Granules ◽  
Sea Urchin Eggs ◽  
Sea Urchin Egg ◽  
Hatching Process ◽  
Fertilization Membrane ◽  
Catalyzed Reactions ◽  
Kinetics Of ◽  
Estrogen Binding

At the time of fertilization, sea urchin eggs release a peroxidase which, together with H2O2 generated by a respiratory burst, is responsible for hardening of the fertilization membrane. We demonstrate here that the ovoperoxidase of unfertilized eggs is located in cortical granules and, after fertilization, is concentrated in the fertilization membrane. Fertilization of sea urchin eggs or their parthenogenetic activation with the ionophor A23187 also results in (a) the conversion of iodide to a trichloroacetic acid-precipitable form (iodination), (b) the deiodination of eggs exogenously labeled with myeloperoxidase and H2O2, (c) the degradation of thyroxine as measured by the recovery of the released radioiodine at the origin and in the inorganic iodide spot on paper chromatography, and (d) the conversion of estradiol to an alcohol-precipitable form (estrogen binding). The iodination reaction and the binding of estradio occurs predominantly in the fertilization membrane where the ovoperoxidase is concentrated. From the estimation of the kinetics of incorporation of iodine, we determine that the peroxidative system is active for 30 min after fertilization, long after hardening of the fertilization membrane is complete. Most of the bound iodine is lost during the hatching process. Iodination of albumin is catalyzed by the material released from the egg during fertilization, when combined with H2O2 and iodide. Iodination, thyroxine degradation, and estradiol binding are inhibited by azide, cyanide, aminotriazole, methimazole, ascorbic acid and ergothioneine, all of which can inhibit peroxidase-catalyzed reactions. These responses of the sea urchin egg to fertilization are strikingly similar to the changes induced in polymorphonuclear leukocytes by phagocytosis and, in both instances, a peroxidative mechanism may be involved.

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