Abstract
Bcl-2 is an integral membrane protein located mainly on the outer membrane of mitochondria. Overexpression of Bcl-2 prevents cells from undergoing apoptosis in response to a variety of stimuli. Cytosolic cytochrome c is necessary for the initiation of the apoptotic program, suggesting a possible connection between Bcl-2 and cytochrome c, which is normally located in the mitochondrial intermembrane space. Cells undergoing apoptosis were found to have an elevation of cytochrome c in the cytosol and a corresponding decrease in the mitochondria. Overexpression of Bcl-2 prevented the efflux of cytochrome c from the mitochondria and the initiation of apoptosis. Thus, one possible role of Bcl-2 in prevention of apoptosis is to block cytochrome c release from mitochondria.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Apoproteins / metabolism
-
Apoptosis*
-
Caspase 3
-
Caspases*
-
Cysteine Endopeptidases / metabolism
-
Cytochrome c Group / metabolism*
-
Cytochromes c
-
Cytosol / metabolism
-
DNA Fragmentation
-
Enzyme Activation
-
Etoposide / pharmacology
-
HL-60 Cells
-
HeLa Cells
-
Humans
-
Intracellular Membranes / metabolism
-
Membrane Potentials / drug effects
-
Mitochondria / metabolism*
-
Poly(ADP-ribose) Polymerases / metabolism
-
Proto-Oncogene Proteins c-bcl-2 / genetics
-
Proto-Oncogene Proteins c-bcl-2 / metabolism*
-
Staurosporine / pharmacology
-
Transfection
Substances
-
Apoproteins
-
Cytochrome c Group
-
Proto-Oncogene Proteins c-bcl-2
-
Etoposide
-
Cytochromes c
-
Poly(ADP-ribose) Polymerases
-
CASP3 protein, human
-
Caspase 3
-
Caspases
-
Cysteine Endopeptidases
-
Staurosporine