Procaspase-9 is attached to the mitochondrial outer membrane in the early stages of apoptosis.
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.
Milisav
Irina
I
Medical Faculty, Institute of Pathophysiology, University of Ljubljana, Zaloska 4, SI-1000, Ljubljana, Slovenia. irina.milisav@mf.uni-lj.si
Suput
Dusan
D
D000818:Animals; D017209:Apoptosis; D053453:Caspase 9 / Q000378:metabolism*; D002478:Cells, Cultured; D003600:Cytosol / Q000737:chemistry / Q000378:metabolism; D004792:Enzyme Precursors / Q000378:metabolism; D022781:Hepatocytes / Q000166:cytology*; D008297:Male; D051336:Mitochondrial Membranes / Q000737:chemistry / Q000378:metabolism*; D021381:Protein Transport; D051381:Rats
D004792:Enzyme Precursors; D053453:Caspase 9