Measurement of intracellular IP3 during Ca2+ oscillations in mouse eggs with GFP-based FRET probe.
Measurement of intracellular IP3 during Ca2+ oscillations in mouse eggs with GFP-based FRET probe.
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DOI：
10.1016/j.bbrc.2006.04.133
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发表时间：
2006-06
影响因子：
3.1
通讯作者：
H. Shirakawa;Masahiko Ito;Moritoshi Sato;Y. Umezawa;S. Miyazaki
中科院分区：
文献类型：
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作者：
H. Shirakawa;Masahiko Ito;Moritoshi Sato;Y. Umezawa;S. Miyazaki
哺乳动物受精卵中的细胞内 Ca2+ 振荡是刺激卵子激活和早期胚胎发育的关键信号，受肌醇 1,4,5-三磷酸 (IP3) 信号通路的调节。我们使用基于两种绿色荧光蛋白变体之间的荧光共振能量转移的荧光探针，研究了受精或卵子激活精子候选因子磷脂酶 C z (PLC z) 表达诱导的 Ca2+ 振荡期间，小鼠卵细胞内 IP3 浓度 ([IP3]i) 的时间变化。荧光测量表明受精卵中的 [IP3]i 升高，并且在 Ca2+ 振荡期间或响应 CaCl2 微量注射时观察到 PLCze 介导的细胞质 Ca2+ 介导的 IP3 产生增强。结果支持了PLC z 是刺激IP3 通路的精子因子的观点，并表明PLC z 活性的高Ca2+ 敏感性和释放的Ca2+ 的正反馈对于触发和维持Ca2+ 振荡很重要。
Intracellular Ca2+oscillations in fertilized mammalian eggs, the key signal that stimulates egg activation and early embryonic development, are regulated by inositol 1,4,5-trisphosphate (IP3) signaling pathway. We investigated temporal changes in intracellular IP3concentration ([IP3]i) in mouse eggs, using a fluorescent probe based on fluorescence resonance energy transfer between two green fluorescent protein variants, during Ca2+oscillations induced by fertilization or expression of phospholipase Cζ (PLCζ), an egg-activating sperm factor candidate. Fluorescence measurements suggested the elevation of [IP3]iin fertilized eggs, and the enhancement of PLCζ-mediated IP3production by cytoplasmic Ca2+was observed during Ca2+oscillations or in response to CaCl2microinjection. The results supported the view that PLCζ is the sperm factor to stimulate IP3pathway, and suggested that high Ca2+sensitivity of PLCζ activity and positive feedback from released Ca2+are important for triggering and maintaining Ca2+oscillations.