|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
First published online August 6, 2009
doi: 10.1242/10.1242/jcs.038166
Commentary |
Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Parkville, Melbourne, Victoria 3050, Australia
* Author for correspondence (kluck{at}wehi.edu.au)
Mitochondrial outer membrane permeabilisation (MOMP) is the point of no return in many forms of apoptotic cell death. The killing effect of MOMP is twofold; it both initiates a proteolytic cascade of pro-apoptotic enzymes and damages mitochondrial function. Accordingly, prevention of MOMP can rescue cells from death. It is clear that either Bak or Bax, which are Bcl-2 family members, are required for MOMP to occur; however, the pore complexes that are formed by Bak and Bax remain poorly defined in terms of their composition, size, number and structure, as well as the mechanism by which they are regulated by other Bcl-2 family members. We recently reported that a key step leading to Bak homo-oligomerisation following an apoptotic stimulus involves transient exposure of the Bak BH3 domain before it binds to the hydrophobic groove of another activated Bak molecule to form a novel symmetric dimer. To form the higher-order oligomers that probably constitute the apoptotic pore complex, Bak dimers then interact via regions away from the BH3 domain and groove. The BH3:groove interaction within Bak homodimers supports a general model to explain the associations between Bcl-2 family members. In this Commentary, we discuss the implications of these findings for the regulation of apoptosis by Bcl-2 family proteins.
Key words: Apoptosis, Bak, Bax, Bcl-2 proteins, Conformation change, Mitochondria, Mitochondrial outer membrane permeabilisation
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati
Twitter What's this?