Effect of Metal Chelators on γ-Secretase Indicates That Calcium and Magnesium Ions Facilitate Cleavage of Alzheimer Amyloid Precursor Substrate.
Gamma-secretase is involved in the production of Aβ amyloid peptides. It cleaves the transmembrane domain of the amyloid precursor protein (APP) at alternative sites to produce Aβ and the APP intracellular domain (AICD). Metal ions play an important role in Aβ aggregation and metabolism, thus metal chelators and ligands represent potential therapeutic agents for AD treatment. A direct effect of metal chelators on γ-secretase has not yet been investigated. The authors used an in vitro  γ-secretase assay consisting of cleavage of APP C100-3XFLAG by endogenous γ-secretase from rodent brains and human neuroblastoma SH-SY5Y, and detected AICD production by western blotting. Adding metalloprotease inhibitors to the reaction showed that clioquinol, phosphoramidon, and zinc metalloprotease inhibitors had no significant effect on γ-secretase activity. In contrast, phenanthroline, EDTA, and EGTA markedly decreased γ-secretase activity that could be restored by adding back calcium and magnesium ions. Mg(2+) stabilized a 1,000 kDa presenilin 1 complex through blue native gel electrophoresis and size-exclusion chromatography. Data suggest that Ca(2+) and Mg(2+) stabilize γ-secretase and enhance its activity.
Department of Pathology, The University of Melbourne, Parkville, VIC 3010, Australia.
Michael
M
Ho
David E
DE
Hoke
Yee Jia
YJ
Chua
Qiao-Xin
QX
Li
Janetta G
JG
Culvenor
Colin
C
Masters
Anthony R
AR
White
Geneviève
G
Evin
J Biol Chem. 2003 Aug 1;278(31):28968-75
12719412
Proc Natl Acad Sci U S A. 2000 May 23;97(11):6138-43
10801983
J Biol Chem. 2005 Apr 1;280(13):12523-35
15613471
Biochemistry. 2002 Feb 26;41(8):2825-35
11851430
Nature. 1987 Feb 19-25;325(6106):733-6
2881207
Curr Opin Neurobiol. 2004 Jun;14(3):379-83
15194119
J Biol Chem. 2005 Dec 23;280(51):41987-96
16236717
J Mol Neurosci. 2004;22(1-2):5-11
14742905
Biochemistry. 2000 Aug 1;39(30):8698-704
10913280
J Biol Chem. 2005 Nov 11;280(45):37689-97
16157587
Nat Med. 2000 Feb;6(2):143-50
10655101
J Neurosci. 2005 Jan 12;25(2):436-45
15647487
J Lipid Res. 2005 May;46(5):1061-7
15722565
Science. 2001 Jul 6;293(5527):115-20
11441186
J Neurosci. 2000 Dec 1;20(23):8745-9
11102481
Biochem Biophys Res Commun. 2006 May 5;343(2):525-34
16546128
FEBS J. 2005 Nov;272(21):5544-57
16262694
CNS Drugs. 2006;20(5):351-72
16696577
Biochemistry. 2004 Aug 3;43(30):9774-89
15274632
Neuron. 2001 Oct 25;32(2):177-80
11683988
Proc Natl Acad Sci U S A. 2006 May 2;103(18):6889-94
16636269
J Biol Chem. 2005 May 6;280(18):17930-7
15722349
Proc Natl Acad Sci U S A. 1999 Mar 30;96(7):3922-7
10097139
Biochemistry. 2005 Mar 22;44(11):4332-41
15766262
Neuron. 2001 Jun;30(3):665-76
11430801
Proc Natl Acad Sci U S A. 2003 Apr 1;100(7):4162-7
12634421
Nature. 1998 Jan 22;391(6665):387-90
9450754
FEBS J. 2007 Aug;274(15):3775-83
17617225
J Neurosci. 1999 Nov 1;19(21):9170-9
10531420
J Mol Neurosci. 2004;23(1-2):105-14
15126696
J Biol Chem. 2001 Jun 15;276(24):21895-901
11278416
J Biol Chem. 2006 Jun 30;281(26):17670-80
16648635
Biophys J. 2002 Nov;83(5):2667-80
12414699
Biochemistry. 1999 Jun 15;38(24):7609-16
10386999
Biochem J. 2000 Oct 15;351 Pt 2:509-16
11023838
Nature. 2010 Sep 2;467(7311):95-8
20811458
Neurobiol Dis. 2004 Jun;16(1):124-32
15207269
J Neurosci. 2006 Oct 25;26(43):10939-48
17065436
Exp Cell Res. 2000 Mar 15;255(2):192-206
10694435
J Neurochem. 2001 Jan;76(1):173-81
11145990
Biochemistry. 2003 Jul 15;42(27):8133-42
12846562
J Biol Chem. 1993 Aug 5;268(22):16109-12
8344894
FEBS Lett. 1994 Jul 25;349(1):109-16
7913895
Science. 1996 Mar 8;271(5254):1406-9
8596911
Biochemistry. 2003 Jan 14;42(1):137-44
12515548
J Lipid Res. 2005 May;46(5):904-12
15716592
Neurobiol Dis. 2002 Feb;9(1):11-23
11848681
Peptides. 2002 Jul;23(7):1285-97
12128085
J Alzheimers Dis. 2009;16(2):225-33
19221414
Nat Cell Biol. 2009 Nov;11(11):1340-6
19838174
J Biol Chem. 2002 Apr 19;277(16):13389-93
11809755
Nature. 1999 Apr 8;398(6727):513-7
10206644
J Biol Chem. 1994 Apr 22;269(16):12152-8
8163520
Cell. 2005 Aug 12;122(3):435-47
16096062
J Biol Chem. 2006 Aug 25;281(34):24566-74
16787929