Mitochondrial Ca 2 1 Dynamics Reveals Limited Intramitochondrial Ca 2 1 Diffusion
Mitochondrial Ca 2 1 Dynamics Reveals Limited Intramitochondrial Ca 2 1 Diffusion
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线粒体 Ca 2 1 动力学揭示有限的线粒体内 Ca 2 1 扩散
DOI：
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
V. Ádám‐Vizi
中科院分区：
文献类型：
--
作者：
A. Gerencser;V. Ádám‐Vizi
为了揭示线粒体功能在单光子水平上的异质性，我们使用宽场荧光成像和数字图像处理技术研究了线粒体Ca 2 1信号传导和线粒体膜电位的时空动态。在这里，我们证明了第一次离散的网站-线粒体内热点-的Ca 2 1摄取后，Ca 2 1释放从细胞内的商店，和传播的Ca 2 1上升线粒体内。通过比较ATP刺激的完整细胞和透化的质膜或暴露于高缓冲液[Ca 2 1 ]的离子载体处理的细胞中的观察结果来表征这种现象。结果表明，Ca 2 1在线粒体内横向扩散，并且扩散限于线粒体网络的较短片段。缓冲扩散的数学模拟支持这些观察结果。用电位染料TMRM测定线粒体膜电位。辐射诱导的TMRM荧光的波动（荧光）在线粒体网络的大区域显示同步性，表明该网络的某些部分形成电合胞体。这些合胞体的空间延伸减少2-氨基乙氧基二苯基硼酸酯（2-APB）或普萘洛尔（非经典的线粒体通透性的阻滞剂）。我们的数据表明，线粒体形成合胞体的电导，而通过的钙2 - 1被限制到个人的细胞器。
To reveal heterogeneity of mitochondrial function on the single-mitochondrion level we have studied the spatiotemporal dynamics of the mitochondrial Ca 2 1 signaling and the mitochondrial membrane potential using wide-field fluorescence imaging and digital image processing techniques. Here we demonstrate first-time discrete sites—intramitochon-drial hotspots—of Ca 2 1 uptake after Ca 2 1 release from intracellular stores, and spreading of Ca 2 1 rise within the mitochondria. The phenomenon was characterized by comparison of observations in intact cells stimulated by ATP and in plasma membrane permeabilized or in ionophore-treated cells exposed to elevated buffer [Ca 2 1 ]. The findings indicate that Ca 2 1 diffuses laterally within the mitochondria, and that the diffusion is limited for shorter segments of the mitochondrial network. These observations were supported by mathematical simulation of buffered diffusion. The mitochondrial membrane potential was investigated using the potentiometric dye TMRM. Irradiation-induced fluctuations (flickering) of TMRM fluorescence showed synchronicity over large regions of the mitochondrial network, indicating that certain parts of this network form electrical syncytia. The spatial extension of these syncytia was decreased by 2-aminoethoxydiphenyl borate (2-APB) or by propranolol (blockers of nonclassical mitochondrial permeabilities). Our data suggest that mitochondria form syncytia of electrical conductance whereas the passage of Ca 2 1 is restricted to the individual organelle.
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影响因子：
--
作者：
S. Arnaudeau;W. Kelley;J. Walsh;N. Demaurex
通讯作者：
S. Arnaudeau;W. Kelley;J. Walsh;N. Demaurex
影响因子：
3.4
作者：
KONISHI, M;OLSON, A;BAYLOR, SM
通讯作者：
BAYLOR, SM
影响因子：
3.4
作者：
FARKAS, DL;WEI, MD;LOEW, LM
通讯作者：
LOEW, LM
影响因子：
4.3
作者：
Fall, CP;Bennett, JP
通讯作者：
Bennett, JP
影响因子：
2.9
作者：
Broekemeier, KM;Klocek, CK;Pfeiffer, DR
通讯作者：
Pfeiffer, DR