TY - JOUR
T1 - Conformational changes in BID, a pro-apoptotic BCL-2 family member, upon membrane binding
T2 - A site-directed spin labeling study
AU - Kyoung, Joon Oh
AU - Barbuto, Scott
AU - Meyer, Natalie
AU - Kim, Ryung Suk
AU - Collier, M. John
AU - Korsmeyer, Stanley J.
PY - 2005/1/7
Y1 - 2005/1/7
N2 - The BCL-2 family proteins constitute a critical control point in apoptosis. BCL-2 family proteins display structural homology to channel-forming bacterial toxins, such as colicins, transmembrane domain of diphtheria toxin, and the N-terminal domain of δ-endotoxin. By analogy, it has been hypothesized the BCL-2 family proteins would unfold and insert into the lipid bilayer upon membrane association. We applied the site-directed spin labeling method of electron paramagnetic resonance spectroscopy to the pro-apoptotic member BID. Here we show that helices 6-8 maintain an α-helical conformation in membranes with a lipid composition resembling mitochondrial outer membrane contact sites. However, unlike colicins and the transmembrane domain of diphtheria toxin, these helices of BID are bound to the lipid bilayer without adopting a transmembrane orientation. Our study presents a more detailed model for the reorganization of the structure of tBID on membranes.
AB - The BCL-2 family proteins constitute a critical control point in apoptosis. BCL-2 family proteins display structural homology to channel-forming bacterial toxins, such as colicins, transmembrane domain of diphtheria toxin, and the N-terminal domain of δ-endotoxin. By analogy, it has been hypothesized the BCL-2 family proteins would unfold and insert into the lipid bilayer upon membrane association. We applied the site-directed spin labeling method of electron paramagnetic resonance spectroscopy to the pro-apoptotic member BID. Here we show that helices 6-8 maintain an α-helical conformation in membranes with a lipid composition resembling mitochondrial outer membrane contact sites. However, unlike colicins and the transmembrane domain of diphtheria toxin, these helices of BID are bound to the lipid bilayer without adopting a transmembrane orientation. Our study presents a more detailed model for the reorganization of the structure of tBID on membranes.
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U2 - 10.1074/jbc.M405428200
DO - 10.1074/jbc.M405428200
M3 - Article
C2 - 15501827
AN - SCOPUS:12844266796
SN - 0021-9258
VL - 280
SP - 753
EP - 767
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 1
ER -