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Free calcium increases explosively in activating medaka eggs.
Open accessAbstract
We have used the calcium-specific light-emitting protein aequorin to follow changes in free calcium concentration during fertilization and cleavage of eggs from medaka, a fresh-water fish. Aequorin-injected medaka eggs show a very low resting glow before they are fertilized, indicating a low calcium concentration in the resting state. Upon activation by sperm, the calcium-mediated light emission increases to a level some 10,000 times the resting level with a 1 to 2 sec time constant for an e-fold increase, and then slowly retruns to the resting level. Upon activation by the ionophore A23187, the early rise in luminescence is much slower, but once a threshold has been reached the subsequent rise becomes as rapid as the normal sperm-induced response. We infer that the explosive rise in calcium involves calcium-stimulated calcium release, and that a sperm normally triggers this rise by somehow inducing a more modest and localized rise in calcium.
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Cited by
The endoplasmic reticulum: structure, function and response to cellular signaling
Schwarz, D. S., & Blower, M. D. (2016) · Cellular and Molecular Life Sciences · doi:10.1007/s00018-015-2052-6 · Cited by 1,613
Sources of calcium in egg activation: A review and hypothesis
Jaffe, L. F. (1983) · Developmental Biology · doi:10.1016/0012-1606(83)90276-2 · Cited by 310
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Metadata
- Authors
- Ridgway, E. B., Gilkey, J. C., & Jaffe, L. F.
- Venue
- Proceedings of the National Academy of Sciences
- Published
- 1977-02
- Volume
- 74
- Issue
- 2
- Pages
- 623-627
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- OpenAlex
- W1977420815
- Cited by
- 373
- References
- 0
- FWCI
- 7.58
- Type
- journal article
- Language
- en
- Open access
- green
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- Ridgway, E. B., Gilkey, J. C., & Jaffe, L. F. (1977). Free calcium increases explosively in activating medaka eggs. Proceedings of the National Academy of Sciences. https://doi.org/10.1073/pnas.74.2.623
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