title: Properties of Ca(2+) transport in mitochondria of Drosophila melanogaster.
abstract: We have studied the pathways for Ca(2+) transport in mitochondria of the fruit fly Drosophila melanogaster. We demonstrate the presence of ruthenium red (RR)-sensitive Ca(2+) uptake, of RR-insensitive Ca(2+) release, and of Na(+)-stimulated Ca(2+) release in energized mitochondria, which match well characterized Ca(2+) transport pathways of mammalian mitochondria. Following larger matrix Ca(2+) loading Drosophila mitochondria underwent spontaneous RR-insensitive Ca(2+) release, an event that in mammals is due to opening of the permeability transition pore (PTP). Like the PTP of mammals, Drosophila Ca(2+)-induced Ca(2+) release could be triggered by uncoupler, diamide, and N-ethylmaleimide, indicating the existence of regulatory voltage- and redox-sensitive sites and was inhibited by tetracaine. Unlike PTP-mediated Ca(2+) release in mammals, however, it was (i) insensitive to cyclosporin A, ubiquinone 0, and ADP; (ii) inhibited by P(i), as is the PTP of yeast mitochondria; and (iii) not accompanied by matrix swelling and cytochrome c release even in KCl-based medium. We conclude that Drosophila mitochondria possess a selective Ca(2+) release channel with features intermediate between the PTP of yeast and mammals.
authors: Consiglio Nazionale delle Ricerche Institute of Neuroscience and Department of Biomedical Sciences, University of I-35121 Padova, Italy.
authors: Sophia
authors: S
authors: von Stockum
authors: Consiglio Nazionale delle Ricerche Institute of Neuroscience and Department of Biomedical Sciences, University of I-35121 Padova, Italy.
authors: Emy
authors: E
authors: Basso
authors: Consiglio Nazionale delle Ricerche Institute of Neuroscience and Department of Biomedical Sciences, University of I-35121 Padova, Italy.
authors: Valeria
authors: V
authors: Petronilli
authors: Institute of Molecular Genetics at the Istituto Ortopedico Rizzoli, I-40126 Bologna, Italy.
authors: Patrizia
authors: P
authors: Sabatelli
authors: Vollum Institute, Oregon Health & Sciences University, Portland, Oregon 97239.
authors: Michael A
authors: MA
authors: Forte
authors: Consiglio Nazionale delle Ricerche Institute of Neuroscience and Department of Biomedical Sciences, University of I-35121 Padova, Italy. Electronic address: bernardi@bio.unipd.it.
authors: Paolo
authors: P
authors: Bernardi
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D000935:Antifungal Agents / Q000494:pharmacology; D016227:Benzoquinones / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D016572:Cyclosporine / Q000494:pharmacology; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster; D004351:Drug Resistance / Q000187:drug effects / Q000502:physiology; D007202:Indicators and Reagents / Q000494:pharmacology; D017136:Ion Transport / Q000187:drug effects / Q000502:physiology; D008322:Mammals / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D033681:Mitochondrial Membrane Transport Proteins / Q000378:metabolism*; D000083162:Mitochondrial Permeability Transition Pore; D012430:Ruthenium Red / Q000494:pharmacology; D013045:Species Specificity; D015003:Yeasts / Q000378:metabolism
chemical_list: D000935:Antifungal Agents; D016227:Benzoquinones; D029721:Drosophila Proteins; D007202:Indicators and Reagents; D033681:Mitochondrial Membrane Transport Proteins; D000083162:Mitochondrial Permeability Transition Pore; D012430:Ruthenium Red; C109863:ubiquinone-O; D000244:Adenosine Diphosphate; D016572:Cyclosporine; D002118:Calcium