Cytosolic inositol 1,4,5-trisphosphate dynamics during intracellular calcium oscillations in living cells.
Cytosolic inositol 1,4,5-trisphosphate dynamics during intracellular calcium oscillations in living cells.
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DOI：
10.1083/jcb.200512141
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发表时间：
2006-06-05
影响因子：
7.8
通讯作者：
Mikoshiba, Katsuhiko
中科院分区：
文献类型：
--
作者：
Matsu-ura, Toru;Michikawa, Takayuki;Inoue, Takafumi;Miyawaki, Atsushi;Yoshida, Manabu;Mikoshiba, Katsuhiko
我们开发了基因编码的荧光肌醇1，4，5-三磷酸（IP 3）传感器，不严重干扰细胞内Ca 2+的动态和使用它们来监测的时空动态的细胞溶质IP 3和Ca 2+在单个HeLa细胞刺激后，外源性表达的代谢型谷氨酸受体5a或内源性组胺受体。在起搏器Ca 2+升高之前，IP 3开始以相对恒定的速率增加，随后的Ca 2+突然升高并不伴随IP 3增加速率的任何加速。胞质[IP 3]没有返回到其基础水平之间的时间间隔Ca 2+尖峰，IP 3逐渐积累在胞质中的Ca 2+振荡过程中有一点或没有波动。这些结果表明，Ca 2+诱导的再生IP 3的生产是不是一个驱动力的上升冲程的Ca 2+尖峰和明显的IP 3的敏感性Ca 2+尖峰产生逐渐下降，在Ca 2+振荡。
We developed genetically encoded fluorescent inositol 1,4,5-trisphosphate (IP3) sensors that do not severely interfere with intracellular Ca2+ dynamics and used them to monitor the spatiotemporal dynamics of both cytosolic IP3 and Ca2+ in single HeLa cells after stimulation of exogenously expressed metabotropic glutamate receptor 5a or endogenous histamine receptors. IP3 started to increase at a relatively constant rate before the pacemaker Ca2+ rise, and the subsequent abrupt Ca2+ rise was not accompanied by any acceleration in the rate of increase in IP3. Cytosolic [IP3] did not return to its basal level during the intervals between Ca2+ spikes, and IP3 gradually accumulated in the cytosol with a little or no fluctuations during cytosolic Ca2+ oscillations. These results indicate that the Ca2+-induced regenerative IP3 production is not a driving force of the upstroke of Ca2+ spikes and that the apparent IP3 sensitivity for Ca2+ spike generation progressively decreases during Ca2+ oscillations.