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Updated: Jun 21, 2026

Isolation and Functional Analysis of Mitochondria from Cultured Cells and Mouse Tissue
Published on: March 23, 2015
The riddle of mitochondrial caspase-3 from liver
Irina Milisav1, Damijan Nipic, Dusan Suput
1Institute of Pathophysiology, University of Ljubljana, Zaloska, Slovenia. irina.milisav@mf.uni-lj.si
Abstract:
Caspase-3 is one of the main executors of apoptosis. Its zymogen procaspase-3 was localized to cytosol, mitochondria and nuclei. The subcellular location of procaspase-3 in liver was reported by several studies to be either cytosolic or cytosolic and mitochondrial. Our aim was to investigate these separate procaspase-3 pools to differentiate the pathways of their activation. By cell fractionation, immunocytochemistry, and confocal microscopy we report that there is a single procaspase-3 pool located to the cytosol in primary hepatocytes and in fractions of rat liver. In contrast, it depends on the isolation purity whether procaspase-3 is located in mitochondria of non-parenchymal liver cells, or not. All preparations with mitochondrial procaspase-3 fractions contain traces of haemoglobin, indicating the presence of some erythrocytes, which are the source of mitochondrial procaspase-3. Since erythrocytes migrate with mitochondria in subcellular fractionations, it is important to check for haemoglobin, before localizing the protein to mitochondria.
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