Abstract
One important result of egg activation is the establishment of blocks to prevent polyspermic fertilization; these blocks are established on the zona pellucida and the egg plasma membrane. This study examines what the sperm brings to the egg to induce the establishment of the membrane block to polyspermy, building on past evidence that membrane block establishment does not occur in response to parthenogenetic stimuli that induce a single transient increase in cytosolic Ca2+ or intracytoplasmic sperm injection (ICSI). We test the hypotheses that (i) sperm-associated Ca2+ release activity triggers membrane block establishment; (ii) introduction of sperm contents via variations on ICSI protocols (resulting in improved Ca2+ transients, egg activation and embryo development over traditional ICSI protocols) triggers membrane block establishment and (iii) sperm adhesion [binding of an extracellular sperm ligand(s) to an egg receptor(s)] combined with sperm-associated Ca2+ release activity triggers membrane block establishment. Interestingly, none of these stimuli induced establishment of the membrane block to polyspermy in mouse eggs. However, the sperm-associated remodeling of the egg cortical cytoskeleton differs between conventionally fertilized and ICSI-fertilized eggs; taken with our previous data implicating actin microfilaments in membrane block establishment, this raises the possibility that cortical reorganization may be a contributing factor. In sum, fertilization-like Ca2+ transients, either alone or combined with sperm - egg binding, are not sufficient for membrane block establishment, but that an event(s) associated with gamete interaction plays a role in this membrane function change.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 557-565 |
| Number of pages | 9 |
| Journal | Molecular Human Reproduction |
| Volume | 13 |
| Issue number | 8 |
| DOIs | |
| State | Published - Aug 2007 |
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Keywords
- Calcium
- Egg activation
- Fertilization
- ICSI
- Polyspermy
ASJC Scopus subject areas
- Obstetrics and Gynecology
- Genetics
- Developmental Biology
- Embryology
- Cell Biology
Cite this
Calcium and sperm components in the establishment of the membrane block to polyspermy : Studies of ICSI and activation with sperm factor. / Wortzman-Show, Genevieve B.; Kurokawa, Manabu; Fissore, Rafael A.; Evans, Janice Perry.
In: Molecular Human Reproduction, Vol. 13, No. 8, 08.2007, p. 557-565.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Calcium and sperm components in the establishment of the membrane block to polyspermy
T2 - Studies of ICSI and activation with sperm factor
AU - Wortzman-Show, Genevieve B.
AU - Kurokawa, Manabu
AU - Fissore, Rafael A.
AU - Evans, Janice Perry
PY - 2007/8
Y1 - 2007/8
N2 - One important result of egg activation is the establishment of blocks to prevent polyspermic fertilization; these blocks are established on the zona pellucida and the egg plasma membrane. This study examines what the sperm brings to the egg to induce the establishment of the membrane block to polyspermy, building on past evidence that membrane block establishment does not occur in response to parthenogenetic stimuli that induce a single transient increase in cytosolic Ca2+ or intracytoplasmic sperm injection (ICSI). We test the hypotheses that (i) sperm-associated Ca2+ release activity triggers membrane block establishment; (ii) introduction of sperm contents via variations on ICSI protocols (resulting in improved Ca2+ transients, egg activation and embryo development over traditional ICSI protocols) triggers membrane block establishment and (iii) sperm adhesion [binding of an extracellular sperm ligand(s) to an egg receptor(s)] combined with sperm-associated Ca2+ release activity triggers membrane block establishment. Interestingly, none of these stimuli induced establishment of the membrane block to polyspermy in mouse eggs. However, the sperm-associated remodeling of the egg cortical cytoskeleton differs between conventionally fertilized and ICSI-fertilized eggs; taken with our previous data implicating actin microfilaments in membrane block establishment, this raises the possibility that cortical reorganization may be a contributing factor. In sum, fertilization-like Ca2+ transients, either alone or combined with sperm - egg binding, are not sufficient for membrane block establishment, but that an event(s) associated with gamete interaction plays a role in this membrane function change.
AB - One important result of egg activation is the establishment of blocks to prevent polyspermic fertilization; these blocks are established on the zona pellucida and the egg plasma membrane. This study examines what the sperm brings to the egg to induce the establishment of the membrane block to polyspermy, building on past evidence that membrane block establishment does not occur in response to parthenogenetic stimuli that induce a single transient increase in cytosolic Ca2+ or intracytoplasmic sperm injection (ICSI). We test the hypotheses that (i) sperm-associated Ca2+ release activity triggers membrane block establishment; (ii) introduction of sperm contents via variations on ICSI protocols (resulting in improved Ca2+ transients, egg activation and embryo development over traditional ICSI protocols) triggers membrane block establishment and (iii) sperm adhesion [binding of an extracellular sperm ligand(s) to an egg receptor(s)] combined with sperm-associated Ca2+ release activity triggers membrane block establishment. Interestingly, none of these stimuli induced establishment of the membrane block to polyspermy in mouse eggs. However, the sperm-associated remodeling of the egg cortical cytoskeleton differs between conventionally fertilized and ICSI-fertilized eggs; taken with our previous data implicating actin microfilaments in membrane block establishment, this raises the possibility that cortical reorganization may be a contributing factor. In sum, fertilization-like Ca2+ transients, either alone or combined with sperm - egg binding, are not sufficient for membrane block establishment, but that an event(s) associated with gamete interaction plays a role in this membrane function change.
KW - Calcium
KW - Egg activation
KW - Fertilization
KW - ICSI
KW - Polyspermy
UR - http://www.scopus.com/inward/record.url?scp=34547789325&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34547789325&partnerID=8YFLogxK
U2 - 10.1093/molehr/gam042
DO - 10.1093/molehr/gam042
M3 - Article
C2 - 17575288
AN - SCOPUS:34547789325
VL - 13
SP - 557
EP - 565
JO - Molecular Human Reproduction
JF - Molecular Human Reproduction
SN - 1360-9947
IS - 8
ER -