Article

Evaluating bistability of Bax activation switch.

State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing 210093, People's Republic of China.
FEBS letters (impact factor: 3.54). 03/2010; 584(5):954-60. DOI:10.1016/j.febslet.2010.01.034 pp.954-60
Source: PubMed

ABSTRACT Mitochondrial apoptotic pathway is precisely controlled by BCL-2 family. Complex interactions of BCL-2 family proteins constitute a bistable switch of which detailed experimental and theoretical delineation remains elusive. In this paper, combined approaches were used to explore the bistability of Bax activation switch. We found that Bax activation is indeed in an 'all-or-none' manner. The 'variable-delay, snap-action' nature for Bax activation is further explored theoretically. We suggest that bistability is largely attributed to topological structure and shows considerable robustness. Therefore, our study characterizes dynamics and sensitivities in intrinsic apoptotic pathway.

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Keywords

'all-or-none' manner
 
Bax activation
 
Complex interactions
 
intrinsic apoptotic pathway
 
Mitochondrial apoptotic pathway
 
sensitivities
 
snap-action' nature
 
study characterizes dynamics
 
theoretical delineation
 
topological structure
 

Tingzhe Sun