Glutathione binding to the Bcl-2 homology-3 domain groove: a molecular basis for Bcl-2 antioxidant function at mitochondria.
Bcl-2 protects cells against mitochondrial oxidative stress and subsequent apoptosis. However, the mechanism underlying the antioxidant function of Bcl-2 is currently unknown. Recently, Bax and several Bcl-2 homology-3 domain (BH3)-only proteins (Bid, Puma, and Noxa) have been shown to induce a pro-oxidant state at mitochondria (1-4). Given the opposing effects of Bcl-2 and Bax/BH3-only proteins on the redox state of mitochondria, we hypothesized that the antioxidant function of Bcl-2 is antagonized by its interaction with the BH3 domains of pro-apoptotic family members. Here, we show that BH3 mimetics that bind to a hydrophobic surface (the BH3 groove) of Bcl-2 induce GSH-sensitive mitochondrial dysfunction and apoptosis in cerebellar granule neurons. BH3 mimetics displace a discrete mitochondrial GSH pool in neurons and suppress GSH transport into isolated rat brain mitochondria. Moreover, BH3 mimetics and the BH3-only protein, Bim, inhibit a novel interaction between Bcl-2 and GSH in vitro. These results suggest that Bcl-2 regulates an essential pool of mitochondrial GSH and that this regulation may depend upon Bcl-2 directly interacting with GSH via the BH3 groove. We conclude that this novel GSH binding property of Bcl-2 likely plays a central role in its antioxidant function at mitochondria.
Zimmermann
Angela K
AK
Eleanor Roosevelt Institute, Department of Biological Sciences, University of Denver, Denver, Colorado 80208, USA.
Loucks
F Alexandra
FA
Schroeder
Emily K
EK
Bouchard
Ron J
RJ
Tyler
Kenneth L
KL
Linseman
Daniel A
DA
D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D017209:Apoptosis; D051023:BH3 Interacting Domain Death Agonist Protein / Q000737:chemistry*; D001921:Brain / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D016877:Oxidants / Q000378:metabolism; D018384:Oxidative Stress; D011485:Protein Binding; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013481:Superoxides / Q000378:metabolism
D000975:Antioxidants; D051023:BH3 Interacting Domain Death Agonist Protein; C494816:Bid protein, rat; D016877:Oxidants; D019253:Proto-Oncogene Proteins c-bcl-2; D013481:Superoxides; D005978:Glutathione
Biochim Biophys Acta. 2004 Mar 1;1644(2-3):83-94
14996493
Free Radic Biol Med. 2004 Mar 1;36(5):542-54
14980699
J Cell Biol. 2004 Jul 19;166(2):193-203
15263017
Hepatology. 2004 Aug;40(2):403-13
15368445
Mol Biol Cell. 2004 Nov;15(11):5001-11
15356267
Cell. 1993 Oct 22;75(2):241-51
7503812
Science. 1993 Nov 19;262(5137):1274-7
8235659
Arch Biochem Biophys. 1994 Oct;314(1):112-9
7944382
J Biol Chem. 1995 Jul 7;270(27):15946-9
7608148
J Biol Chem. 1995 Sep 8;270(36):21035-9
7673130
J Neurochem. 1996 Sep;67(3):1259-67
8752134
Ann Neurol. 1996 Sep;40(3):379-86
8797527
Proc Natl Acad Sci U S A. 1998 Mar 17;95(6):2956-60
9501197
J Neurosci. 1998 Oct 15;18(20):8145-52
9763461
J Neurochem. 1998 Aug;71(2):741-8
9681465
J Neurosci. 1998 May 1;18(9):3241-50
9547233
Proc Natl Acad Sci U S A. 1998 Oct 27;95(22):12896-901
9789011
Exp Neurol. 1999 Aug;158(2):428-36
10415149
Cancer Res. 2005 Mar 1;65(5):1647-54
15753358
NeuroRx. 2005 Jul;2(3):484-94
16389312
J Neurosci. 2006 May 10;26(19):5256-64
16687518
J Neurochem. 2006 Aug;98(4):1141-8
16895581
Chem Biol Interact. 2006 Oct 27;163(1-2):54-67
16600197
J Neuropathol Exp Neurol. 2000 Jan;59(1):53-61
10744035
Proc Natl Acad Sci U S A. 2000 Jun 20;97(13):7124-9
10860979
J Neurosci. 2000 Dec 15;20(24):9119-25
11124989
Cell Death Differ. 2000 Dec;7(12):1146-54
11175251
Proc Natl Acad Sci U S A. 2001 Feb 27;98(5):2837-42
11226327
Nat Rev Mol Cell Biol. 2001 Jan;2(1):67-71
11413468
J Med Chem. 2001 Dec 6;44(25):4313-24
11728179
J Neurosci. 2002 Aug 1;22(15):6480-90
12151527
J Neurosci. 2002 Nov 1;22(21):9287-97
12417654
Histochem Cell Biol. 2003 Oct;120(4):327-33
14574588
J Exp Med. 2004 Jan 5;199(1):113-24
14699081
Neuron. 2004 Jul 8;43(1):19-30
15233914