دورية أكاديمية

Reconstitution of the anti-apoptotic Bcl-2 protein into lipid membranes and biophysical evidence for its detergent-driven association with the pro-apoptotic Bax protein.

التفاصيل البيبلوغرافية
العنوان: Reconstitution of the anti-apoptotic Bcl-2 protein into lipid membranes and biophysical evidence for its detergent-driven association with the pro-apoptotic Bax protein.
المؤلفون: Marcus Wallgren, Martin Lidman, Anders Pedersen, Kristoffer Brännström, B Göran Karlsson, Gerhard Gröbner
المصدر: PLoS ONE, Vol 8, Iss 4, p e61452 (2013)
بيانات النشر: Public Library of Science (PLoS), 2013.
سنة النشر: 2013
المجموعة: LCC:Medicine
LCC:Science
مصطلحات موضوعية: Medicine, Science
الوصف: The anti-apoptotic B-cell CLL/lymphoma-2 (Bcl-2) protein and its counterpart, the pro-apoptotic Bcl-2-associated X protein (Bax), are key players in the regulation of the mitochondrial pathway of apoptosis. However, how they interact at the mitochondrial outer membrane (MOM) and there determine whether the cell will live or be sentenced to death remains unknown. Competing models have been presented that describe how Bcl-2 inhibits the cell-killing activity of Bax, which is common in treatment-resistant tumors where Bcl-2 is overexpressed. Some studies suggest that Bcl-2 binds directly to and sequesters Bax, while others suggest an indirect process whereby Bcl-2 blocks BH3-only proteins and prevents them from activating Bax. Here we present the results of a biophysical study in which we investigated the putative interaction of solubilized full-length human Bcl-2 with Bax and the scope for incorporating the former into a native-like lipid environment. Far-UV circular dichroism (CD) spectroscopy was used to detect direct Bcl-2-Bax-interactions in the presence of polyoxyethylene-(23)-lauryl-ether (Brij-35) detergent at a level below its critical micelle concentration (CMC). Additional surface plasmon resonance (SPR) measurements confirmed this observation and revealed a high affinity between the Bax and Bcl-2 proteins. Upon formation of this protein-protein complex, Bax also prevented the binding of antimycin A2 (a known inhibitory ligand of Bcl-2) to the Bcl-2 protein, as fluorescence spectroscopy experiments showed. In addition, Bcl-2 was able to form mixed micelles with Triton X-100 solubilized neutral phospholipids in the presence of high concentrations of Brij-35 (above its CMC). Following detergent removal, the integral membrane protein was found to have been fully reconstituted into a native-like membrane environment, as confirmed by ultracentrifugation and subsequent SDS-PAGE experiments.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1932-6203
Relation: http://europepmc.org/articles/PMC3634071?pdf=render; https://doaj.org/toc/1932-6203
DOI: 10.1371/journal.pone.0061452
URL الوصول: https://doaj.org/article/80da6c0cb0e34a3aa4be47a1b16738a6
رقم الأكسشن: edsdoj.80da6c0cb0e34a3aa4be47a1b16738a6
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:19326203
DOI:10.1371/journal.pone.0061452