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Mitochondrial Ca2+ Handling and Behind: The Importance of Being in Contact with Other Organelles

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Molecular Basis for Mitochondrial Signaling

Abstract

Calcium (Ca2+) is one of the main intracellular signals used by the cell to transmit and translate extracellular inputs into specific function activation. A complex web, formed by different interconnected cellular structures, and able to take up and release the cation, is present throughout the cell and controls Ca2+ dynamics under physiological and pathological conditions. Among different organelles, mitochondria represent a central hub of this net and make diverse physical and functional couplings with several other intracellular structures, fundamental not only for Ca2+ signaling but also for multiple pathways regulating the cell fate. In this chapter, we update mitochondria-organelles connections, with a special attention at Ca2+ crosstalk, from different points of view: the intracellular conditions that allow the mitochondrion to be one of the most important Ca2+ modulator, the different connections undertaken by mitochondria with several organelles and the functional consequences of these couplings, the molecules involved in the formation/modulation of these inter-organelles structures, and the most studied diseases in which alterations of these relationships have been reported to play a pathogenic role.

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Acknowledgments

The authors thank grants from the University of Padova, the Italian Ministry of University and Scientific Research, Fondazione Cassa di Risparmio di Padova e Rovigo (CARIPARO Foundation; Progetti d’eccellenza 2011/2012), and EU Joint Programme in Neurodegenerative Disease, 2015–2018, “Cellular Bioenergetics in Neurodegenerative Diseases: A system-based pathway and target analysis,” for their support of the research work performed in their lab. P.T. is research fellow of the EU Joint Programme – Neurodegenerative Disease.

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Filadi, R., Theurey, P., Rossi, A., Fedeli, C., Pizzo, P. (2017). Mitochondrial Ca2+ Handling and Behind: The Importance of Being in Contact with Other Organelles. In: Rostovtseva, T. (eds) Molecular Basis for Mitochondrial Signaling. Biological and Medical Physics, Biomedical Engineering. Springer, Cham. https://doi.org/10.1007/978-3-319-55539-3_1

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