Abstract
In contrast to the well-defined role of Ca2+ signals during mitosis, the contribution of Ca2+ signaling to meiosis progression is controversial, despite several decades of investigating the role of Ca 2+ and its effectors in vertebrate oocyte maturation. We have previously shown that during Xenopus oocyte maturation, Ca2+ signals are dispensable for entry into meiosis and for germinal vesicle breakdown. However, normal Ca2+ homeostasis is essential for completion of meiosis I and extrusion of the first polar body. In this study, we test the contribution of several downstream effectors in mediating the Ca2+ effects during oocyte maturation. We show that calmodulin and calcium-calmodulin-dependent protein kinase II (CAMK2) are not critical downstream Ca2+ effectors during meiotic maturation. In contrast, accumulation of Aurora kinase A (AURKA) protein is disrupted in cells deprived of Ca2+ signals. Since AURKA is required for bipolar spindle formation, failure to accumulate AURKA may contribute to the defective spindle phenotype following Ca2+ deprivation. These findings argue that Ca2+ homeostasis is important in establishing the oocyte's competence to undergo maturation in preparation for fertilization and embryonic development.
| Original language | English |
|---|---|
| Pages (from-to) | 726-735 |
| Number of pages | 10 |
| Journal | Biology of Reproduction |
| Volume | 78 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - Apr 2008 |
| Externally published | Yes |
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Keywords
- Aurora kinase A
- Calcium
- Gamete biology
- Meiosis
- Oocyte development
ASJC Scopus subject areas
- Cell Biology
- Developmental Biology
- Embryology
Cite this
Ca2+ homeostasis regulates Xenopus oocyte maturation. / Sun, Lu; Hodeify, Rawad; Haun, Shirley; Charlesworth, Amanda; MacNicol, Angus M.; Ponnappan, Subramaniam; Ponnappan, Usha; Prigent, Claude; Machaca, Khaled.
In: Biology of Reproduction, Vol. 78, No. 4, 04.2008, p. 726-735.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Ca2+ homeostasis regulates Xenopus oocyte maturation
AU - Sun, Lu
AU - Hodeify, Rawad
AU - Haun, Shirley
AU - Charlesworth, Amanda
AU - MacNicol, Angus M.
AU - Ponnappan, Subramaniam
AU - Ponnappan, Usha
AU - Prigent, Claude
AU - Machaca, Khaled
PY - 2008/4
Y1 - 2008/4
N2 - In contrast to the well-defined role of Ca2+ signals during mitosis, the contribution of Ca2+ signaling to meiosis progression is controversial, despite several decades of investigating the role of Ca 2+ and its effectors in vertebrate oocyte maturation. We have previously shown that during Xenopus oocyte maturation, Ca2+ signals are dispensable for entry into meiosis and for germinal vesicle breakdown. However, normal Ca2+ homeostasis is essential for completion of meiosis I and extrusion of the first polar body. In this study, we test the contribution of several downstream effectors in mediating the Ca2+ effects during oocyte maturation. We show that calmodulin and calcium-calmodulin-dependent protein kinase II (CAMK2) are not critical downstream Ca2+ effectors during meiotic maturation. In contrast, accumulation of Aurora kinase A (AURKA) protein is disrupted in cells deprived of Ca2+ signals. Since AURKA is required for bipolar spindle formation, failure to accumulate AURKA may contribute to the defective spindle phenotype following Ca2+ deprivation. These findings argue that Ca2+ homeostasis is important in establishing the oocyte's competence to undergo maturation in preparation for fertilization and embryonic development.
AB - In contrast to the well-defined role of Ca2+ signals during mitosis, the contribution of Ca2+ signaling to meiosis progression is controversial, despite several decades of investigating the role of Ca 2+ and its effectors in vertebrate oocyte maturation. We have previously shown that during Xenopus oocyte maturation, Ca2+ signals are dispensable for entry into meiosis and for germinal vesicle breakdown. However, normal Ca2+ homeostasis is essential for completion of meiosis I and extrusion of the first polar body. In this study, we test the contribution of several downstream effectors in mediating the Ca2+ effects during oocyte maturation. We show that calmodulin and calcium-calmodulin-dependent protein kinase II (CAMK2) are not critical downstream Ca2+ effectors during meiotic maturation. In contrast, accumulation of Aurora kinase A (AURKA) protein is disrupted in cells deprived of Ca2+ signals. Since AURKA is required for bipolar spindle formation, failure to accumulate AURKA may contribute to the defective spindle phenotype following Ca2+ deprivation. These findings argue that Ca2+ homeostasis is important in establishing the oocyte's competence to undergo maturation in preparation for fertilization and embryonic development.
KW - Aurora kinase A
KW - Calcium
KW - Gamete biology
KW - Meiosis
KW - Oocyte development
UR - http://www.scopus.com/inward/record.url?scp=41549140994&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=41549140994&partnerID=8YFLogxK
U2 - 10.1095/biolreprod.107.063693
DO - 10.1095/biolreprod.107.063693
M3 - Article
C2 - 18094360
AN - SCOPUS:41549140994
VL - 78
SP - 726
EP - 735
JO - Biology of Reproduction
JF - Biology of Reproduction
SN - 0006-3363
IS - 4
ER -