Acidic pH promotes oligomerization and membrane insertion of the BclXL apoptotic repressor.

ABSTRACT: Solution pH is believed to serve as an intricate regulatory switch in the induction of apoptosis central to embryonic development and cellular homeostasis. Herein, using an array of biophysical techniques, we provide evidence that acidic pH promotes the assembly of BclXL apoptotic repressor into a megadalton oligomer with a plume-like appearance and harboring structural features characteristic of a molten globule. Strikingly, our data reveal that pH tightly modulates not only oligomerization but also ligand binding and membrane insertion of BclXL in a highly subtle manner. Thus, while oligomerization and the accompanying molten globular content of BclXL is least favorable at pH 6, both of these structural features become more pronounced under acidic and alkaline conditions. However, membra

SUBMITTER: Bhat V 

PROVIDER: S-EPMC3483416 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature