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Updated: Mar 20, 2026

Experimental Approaches to Study Mitochondrial Localization and Function of a Nuclear Cell Cycle Kinase, Cdk1
Published on: February 25, 2016
Spermine cycling in mitochondria is mediated by adenine nucleotide translocase activity: mechanism and
Silvia Grancara1, Lisa Dalla Via2, Aida Nelly García-Argáez2
1Department of Biochemical Sciences, SAPIENZA University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
Abstract:
Spermine, besides to be transported in mitochondria by an energy dependent electrophoretic mechanism, can be also released by two different mechanisms. The first one is induced in deenergizing conditions by FCCP or antimycin A and it is mediated by an electroneutral exchange spermine protons. The second one takes place in energizing conditions during the activity of the adenine nucleotide translocase and is mediated by an electroneutral symport mechanism involving the efflux in co-transport of spermine and phosphate and the exchange of exogenous ADP with endogenous ATP. The triggering of this mechanism permits an alternating cycling of spermine across the mitochondrial membrane, that is spermine is transported or released by energized mitochondria in the absence or presence of ATP synthesis, respectively. The physiological implications of this cycling of spermine are related to the induction or prevention of mitochondrial permeability transition and, consequently, on apoptosis or its prevention.
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