When Isolated at Full Receptivity, in Vitro Fertilized Wheat (Triticum aestivum, L.) Egg Cells Reveal [Ca2+]cyt Oscillation of Intracellular Origin

International Journal of Molecular Sciences

Zsolt Pónya⁴  Ilaria Corsi²  Richárd Hoffmann⁴  Melinda Kovผs⁵  Anikó Dobosy⁴  Attila Zoltán Kovผs³  Mauro Cresti²  Beáta Barnabás¹ 

[1] Department of Plant Cell Biology, Agricultural Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, Martonvàsàr H-2462, Hungary; E-Mail:;Dipartimento di Scienze Ambientali “G. Sarfatti”, University of Siena, Siena 53100, Italy; E-Mails:;Department of Technology of Animal Breeding and Management, Faculty of Agricultural and Environmental Sciences Kaposvár University, Kaposvár H-7400, Hungary; E-Mail:;Department of Plant Production and Plant Protection, Institute of Plant Science, Faculty of Agricultural and Environmental Sciences, Kaposvár University, Kaposvár H-7400, Hungary; E-Mails:;Institute of Physiology, Biochemistry and Animal Health, Faculty of Agricultural and Environmental Sciences, Kaposvár University, Kaposvár H-7400, Hungary; E-Mail:

关键词: in vitro fertilization;    wheat (Triticum aestivum;    L.) egg cell;    cytosolic calcium;    egg activation;    thapsigargin;    intracellular Ca²⁺ store;    endoplasmic reticulum;   

DOI  :  10.3390/ijms151223766

来源: mdpi

【 摘 要 】

During in vitro fertilization of wheat (Triticum aestivum, L.) in egg cells isolated at various developmental stages, changes in cytosolic free calcium ([Ca²⁺]_cyt) were observed. The dynamics of [Ca²⁺]_cyt elevation varied, reflecting the difference in the developmental stage of the eggs used. [Ca²⁺]_cyt oscillation was exclusively observed in fertile, mature egg cells fused with the sperm cell. To determine how [Ca²⁺]_cyt oscillation in mature egg cells is generated, egg cells were incubated in thapsigargin, which proved to be a specific inhibitor of the endoplasmic reticulum (ER) Ca²⁺-ATPase in wheat egg cells. In unfertilized egg cells, the addition of thapsigargin caused an abrupt transient increase in [Ca²⁺]_cyt in the absence of extracellular Ca²⁺, suggesting that an influx pathway for Ca²⁺ is activated by thapsigargin. The [Ca²⁺]_cyt oscillation seemed to require the filling of an intracellular calcium store for the onset of which, calcium influx through the plasma membrane appeared essential. This was demonstrated by omitting extracellular calcium from (or adding GdCl₃ to) the fusion medium, which prevented [Ca²⁺]_cyt oscillation in mature egg cells fused with the sperm. Combined, these data permit the hypothesis that the first sperm-induced transient increase in [Ca²⁺]_cyt depletes an intracellular Ca²⁺ store, triggering an increase in plasma membrane Ca²⁺ permeability, and this enhanced Ca²⁺ influx results in [Ca²⁺]_cyt oscillation.

【 授权许可】

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