Sci. STKE, 31 October 2000
Apoptosis Akt Protects Cells from Cytochrome c
Neuronal survival mediated by phosphoinositide 3-kinase activation involves the activation of a downstream kinase Akt. Zhou et al. used hybrid motor neurons transfected with constitutively active Akt to show that overexpression of Akt blocks ceramide-induced apoptosis. Constitutively active Akt did not block the release of cytochrome c into the cytosol; however, it did protect cells from microinjected cytochrome c. This suggests that Akt inhibits apoptosis downstream of cytochrome c, which is released from mitochondria in response to proapoptotic stimuli. Further support for the placement of the antiapoptotic activity of Akt downstream of cytochrome c came from cell-free assays in which Akt inhibited caspase activation and cleavage of poly (ADP ribose) polymerase (PARP) by cytochrome c.
Citation: Akt Protects Cells from Cytochrome c. Sci. STKE 2000, tw9 (2000).
Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882