Send to

Choose Destination
Cell Death Differ. 2005 Jul;12(7):783-95.

Cellular prion protein inhibits proapoptotic Bax conformational change in human neurons and in breast carcinoma MCF-7 cells.

Author information

The Bloomfield Center for Research in Aging, Lady Davis Institute for Medical Research, The Sir Mortimer B Davis Jewish General Hospital, Montréal, Québec, Canada.


Prion protein (PrP) prevents Bcl-2-associated protein X (Bax)-mediated cell death, but the step at which PrP inhibits is not known. We first show that PrP is very specific for Bax and cannot prevent Bak (Bcl-2 antagonist killer 1)-, tBid-, staurosporine- or thapsigargin-mediated cell death. As Bax activation involves Bax conformational change, mitochondrial translocation, cytochrome c release and caspase activation, we investigated which of these events was inhibited by PrP. PrP inhibits Bax conformational change, cytochrome c release and cell death in human primary neurons and MCF-7 cells. Serum deprivation-induced Bax conformational change is more rapid in PrP-null cells. PrP does not prevent active caspase-mediated cell death. PrP does not colocalize with Bax in normal or apoptotic primary neurons and cannot prevent Bax-mediated cytochrome c release in a mitochondrial cell-free system. We conclude that PrP protects against Bax-mediated cell death by preventing the Bax proapoptotic conformational change that occurs initially in Bax activation.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center