Mouse sperm-egg fusion was examined using two-photon and confocal
microscopy. A delay of several minutes occurred between the first
observable event of fusion (which was the diffusion of Ca$^2+$-sensitive
dyes from egg into sperm) and any change in egg cytoplasmic Ca$^2+$.
When indo-1 dextran was used to obtain ratiometric two-photon images,
there was no detectable local increase in egg cytoplasmic Ca$^2+$
near the site of sperm fusion. However, the sperm underwent a Ca$^2+$
transient which appeared to be coincident with the egg cytoplasm
Ca$^2+$ transient, which suggested that there was a high permeability
pathway for Ca$^2+$ between egg and sperm. To exclude this pathway
from providing trigger Ca$^2+$ for the egg transient, we reduced
bathing Ca$^2+$ to approx. 18 microM and 13nM (with EGTA).
In these conditions the first egg Ca$^2+$ transient was not prevented,
which makes an obligatory role for extracellular Ca$^2+$ in the
initiation of the egg Ca$^2+$ transient unlikely. Both FITC-albumin
(70 kDa) and 10 kDa dextran-linked Ca$^2+$ indicators were able
to diffuse into the sperm from the egg. In addition, phycoerythrin
(240 kDa) rapidly diffused into the sperm shortly after fusion (but
before any changes in Ca$^2+$ occurred). This suggests that the
'pore(s)' that form during sperm-egg fusion must be at least 8 nm
in diameter. These data are compatible with the idea that a diffusible
sperm protein could trigger the observed changes in intracellular
Ca$^2+$ in the egg, but do not exclude the possibility that other
second messengers are generated during sperm-egg fusion.
%0 Journal Article
%1 Jone_1998_4627
%A Jones, K. T.
%A Soeller, C.
%A Cannell, M. B.
%D 1998
%J Development
%K Acetic Acid Acid, Acids, Action Activation, Adaptation, Adenosine Adhesion, Agents, Algorithms, Allergens, Allergic, Alternative Amino Aniline Animals, Antibodies, Antibody Antigens, Antipain, Auditory Biological Biological, Biosensing Bronchi, Butyric Cadherins, Calcium Calcium, Cardiac, Cardiovascular, Carrier Cell Cells, Channels, Cheese, Chelating Cilia, Cochlea, Communication, Comparative Compartmentation, Compounds, Computer Computer-Assisted, Conductivity, Confocal, Connexins, Crystalline, Crystallins, Culture Cultured, Cysteine Dermatophagoides, Desmosomes, Dextrans, Diagnostic Differentiation, Diffusion, Dogs, Dyes, Electric Electrochemistry, Electrophysiology, Endopeptidases, Enzyme Epithelial Epithelium, Epitopes, Ethylenediamines, Feasibility Feces, Feedback, Female, Fertilization, Fluorescein, Fluorescein-5-isothiocyanate, Fluorescence, Fluorescent Imaging, Impedance, Inhibitors, Line, Membrane Membrane, Perception, Permeability, Potentials, Proteins, Sequence, Signaling, Simulation, Splicing, Stimulation, Studies, Study, Technique, Techniques, Transport, Triphosphate,
%N 23
%P 4627-35
%T The passage of Ca$^2+$ and fluorescent markers between the sperm
and egg after fusion in the mouse.
%U http://dev.biologists.org/cgi/reprint/125/23/4627
%V 125
%X Mouse sperm-egg fusion was examined using two-photon and confocal
microscopy. A delay of several minutes occurred between the first
observable event of fusion (which was the diffusion of Ca$^2+$-sensitive
dyes from egg into sperm) and any change in egg cytoplasmic Ca$^2+$.
When indo-1 dextran was used to obtain ratiometric two-photon images,
there was no detectable local increase in egg cytoplasmic Ca$^2+$
near the site of sperm fusion. However, the sperm underwent a Ca$^2+$
transient which appeared to be coincident with the egg cytoplasm
Ca$^2+$ transient, which suggested that there was a high permeability
pathway for Ca$^2+$ between egg and sperm. To exclude this pathway
from providing trigger Ca$^2+$ for the egg transient, we reduced
bathing Ca$^2+$ to approx. 18 microM and 13nM (with EGTA).
In these conditions the first egg Ca$^2+$ transient was not prevented,
which makes an obligatory role for extracellular Ca$^2+$ in the
initiation of the egg Ca$^2+$ transient unlikely. Both FITC-albumin
(70 kDa) and 10 kDa dextran-linked Ca$^2+$ indicators were able
to diffuse into the sperm from the egg. In addition, phycoerythrin
(240 kDa) rapidly diffused into the sperm shortly after fusion (but
before any changes in Ca$^2+$ occurred). This suggests that the
'pore(s)' that form during sperm-egg fusion must be at least 8 nm
in diameter. These data are compatible with the idea that a diffusible
sperm protein could trigger the observed changes in intracellular
Ca$^2+$ in the egg, but do not exclude the possibility that other
second messengers are generated during sperm-egg fusion.
@article{Jone_1998_4627,
abstract = {Mouse sperm-egg fusion was examined using two-photon and confocal
microscopy. A delay of several minutes occurred between the first
observable event of fusion (which was the diffusion of {C}a$^{2+}$-sensitive
dyes from egg into sperm) and any change in egg cytoplasmic {C}a$^{2+}$.
When indo-1 dextran was used to obtain ratiometric two-photon images,
there was no detectable local increase in egg cytoplasmic {C}a$^{2+}$
near the site of sperm fusion. However, the sperm underwent a {C}a$^{2+}$
transient which appeared to be coincident with the egg cytoplasm
{C}a$^{2+}$ transient, which suggested that there was a high permeability
pathway for {C}a$^{2+}$ between egg and sperm. To exclude this pathway
from providing trigger {C}a$^{2+}$ for the egg transient, we reduced
bathing [{C}a$^{2+}$] to approx. 18 microM and 13nM (with EGTA).
In these conditions the first egg {C}a$^{2+}$ transient was not prevented,
which makes an obligatory role for extracellular {C}a$^{2+}$ in the
initiation of the egg {C}a$^{2+}$ transient unlikely. Both {FITC}-albumin
(70 kDa) and 10 kDa dextran-linked {C}a$^{2+}$ indicators were able
to diffuse into the sperm from the egg. In addition, phycoerythrin
(240 kDa) rapidly diffused into the sperm shortly after fusion (but
before any changes in {C}a$^{2+}$ occurred). This suggests that the
'pore(s)' that form during sperm-egg fusion must be at least 8 nm
in diameter. These data are compatible with the idea that a diffusible
sperm protein could trigger the observed changes in intracellular
{C}a$^{2+}$ in the egg, but do not exclude the possibility that other
second messengers are generated during sperm-egg fusion.},
added-at = {2009-06-03T11:20:58.000+0200},
author = {Jones, K. T. and Soeller, C. and Cannell, M. B.},
biburl = {https://www.bibsonomy.org/bibtex/2cc2e27202ec41f636eb3ec6a387d0f8d/hake},
description = {The whole bibliography file I use.},
file = {Jone_1998_4627.pdf:Jone_1998_4627.pdf:PDF},
interhash = {af77dcb29750167eeac13a00e5ac6b95},
intrahash = {cc2e27202ec41f636eb3ec6a387d0f8d},
journal = {Development},
keywords = {Acetic Acid Acid, Acids, Action Activation, Adaptation, Adenosine Adhesion, Agents, Algorithms, Allergens, Allergic, Alternative Amino Aniline Animals, Antibodies, Antibody Antigens, Antipain, Auditory Biological Biological, Biosensing Bronchi, Butyric Cadherins, Calcium Calcium, Cardiac, Cardiovascular, Carrier Cell Cells, Channels, Cheese, Chelating Cilia, Cochlea, Communication, Comparative Compartmentation, Compounds, Computer Computer-Assisted, Conductivity, Confocal, Connexins, Crystalline, Crystallins, Culture Cultured, Cysteine Dermatophagoides, Desmosomes, Dextrans, Diagnostic Differentiation, Diffusion, Dogs, Dyes, Electric Electrochemistry, Electrophysiology, Endopeptidases, Enzyme Epithelial Epithelium, Epitopes, Ethylenediamines, Feasibility Feces, Feedback, Female, Fertilization, Fluorescein, Fluorescein-5-isothiocyanate, Fluorescence, Fluorescent Imaging, Impedance, Inhibitors, Line, Membrane Membrane, Perception, Permeability, Potentials, Proteins, Sequence, Signaling, Simulation, Splicing, Stimulation, Studies, Study, Technique, Techniques, Transport, Triphosphate,},
month = Dec,
number = 23,
pages = {4627-35},
timestamp = {2009-06-03T11:21:17.000+0200},
title = {The passage of {C}a$^{2+}$ and fluorescent markers between the sperm
and egg after fusion in the mouse.},
url = {http://dev.biologists.org/cgi/reprint/125/23/4627},
volume = 125,
year = 1998
}