Procaspase-9 is attached to the mitochondrial outer membrane in the early stages of apoptosis
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Lighting Up the Pathways to Caspase Activation Using Bimolecular Fluorescence Complementation
Published on: March 5, 2018
1Medical Faculty, Institute of Pathophysiology, University of Ljubljana, Zaloska 4, SI-1000, Ljubljana, Slovenia. irina.milisav@mf.uni-lj.si
Abstract:
Procaspase-9 is the zymogen form of one of the apoptosis initiators, caspase-9. Its cellular location may differ depending on the cell type; it is found throughout the cytosol, although some of it may be associated with the mitochondria. Procaspase-9 relocates from the cytosol to the mitochondria shortly after the triggering of apoptosis in rat hepatocytes. We investigated whether the mitochondrial protein import machineries import procaspase-9. The combined results of protein import analyses, mitochondrial fractionation and protease treatments of intact and swollen mitochondria imply that procaspase-9 attaches to the outer surface of the mitochondrial outer membrane.
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