Caporale Teresa, Ciavardelli Domenico, Di Ilio Carmine, Lanuti Paola, Drago Denise, Sensi Stefano L
Department of Basic and Applied Medical Science, Center for Excellence on Aging, University 'G. d'Annunzio', Chieti, Italy.
Exp Neurol. 2009 Aug;218(2):228-34. doi: 10.1016/j.expneurol.2009.04.003. Epub 2009 Apr 15.
Zn(2+) can enter mitochondria and promote a plethora of physiological and patho-physiological effects. The issue of measuring changes in intramitochondrial levels is therefore critical. Past studies have employed fluorescent Zn(2+) indicators, like Rhod-2 and RhodZin-3, however, the use of these probes is impaired by their extramitochondrial sequestration. In this study, we show that the ratiometric mitochondria-targeted pericam, RPmt, can be employed to detect changes of intramitochondrial free Zn(2+) (Zn(2+)) levels. Using RPmt in neuronal and non neuronal cell lines we demonstrate that mitochondria can take up the cation mobilized from the cytosolic pool of protein-bound Zn(2+) and that mitochondrial Zn(2+) sequestration is largely mediated by the activity of the Ca(2+) uniporter.
锌离子（Zn²⁺）可进入线粒体，并引发大量生理和病理生理效应。因此，测量线粒体内锌离子水平变化的问题至关重要。过去的研究采用了诸如罗丹明-2（Rhod-2）和罗丹锌-3（RhodZin-3）等荧光锌离子指示剂，然而，这些探针的线粒体外螯合作用影响了它们的使用。在本研究中，我们表明，比率型线粒体靶向钙敏蛋白（RPmt）可用于检测线粒体内游离锌离子（[Zn²⁺]m）水平的变化。在神经元和非神经元细胞系中使用RPmt，我们证明线粒体可以摄取从与蛋白质结合的锌离子的胞质池中动员出来的阳离子，并且线粒体锌离子螯合主要由钙离子单向转运体的活性介导。
