Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Echinobase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
Echinobase
ECB-ART-30201
Dev Biol 1977 Jul 01;581:185-96. doi: 10.1016/0012-1606(77)90084-7.
Show Gene links Show Anatomy links

Intracellular calcium release at fertilization in the sea urchin egg.

Steinhardt R , Zucker R , Schatten G .


???displayArticle.abstract???
Fertilization or ionophore activation of Lytechinus pictus eggs can be monitored after injection with the Ca-sensitive photoprotein aequorin to estimate calcium release during activation. We estimate the peak calcium transient to reach concentrations of 2.5–4.5 μM free calcium 45–60 sec after activation and to last 2–3 min, assuming equal Ca2+ release throughout the cytoplasm. Calcium is released from an intracellular store, since similar responses are obtained during fertilization at a wide range of external calcium concentrations or in zero-calcium seawater in ionophore activations. In another effort to estimate free calcium at fertilization, we isolated egg cortices, added back calcium quantitatively, and fixed for observation with a scanning electron microscope. In this way, we determined that the threshold for discharge of the cortical granules is between 9 and 18 μM Ca2+. Therefore, the threshold for the in vitro cortical reaction is about five times the amount of free calcium, assuming equal distribution in the egg. This result suggests that transient calcium release is confined to the inner subsurface of the egg.

???displayArticle.pubmedLink??? 326602
???displayArticle.pmcLink??? PMC4351706
???displayArticle.link??? Dev Biol
???displayArticle.grants??? [+]

Genes referenced: LOC100887844

References [+] :
Azarnia, The role of divalent cations in activation of the sea urchin egg. I. Effect of fertilization on divalent cation content. 1976, Pubmed, Echinobase