Presenilin-1 and -2 are molecular targets for gamma-secretase inhibitors.
Presenilins are integral membrane protein involved in the production of amyloid beta-protein. Mutations of the presenilin-1 and -2 gene are associated with familial Alzheimer's disease and are thought to alter gamma-secretase cleavage of the beta-amyloid precursor protein, leading to increased production of longer and more amyloidogenic forms of A beta, the 4-kDa beta-peptide. Here, we show that radiolabeled gamma-secretase inhibitors bind to mammalian cell membranes, and a benzophenone analog specifically photocross-links three major membrane polypeptides. A positive correlation is observed among these compounds for inhibition of cellular A beta formation, inhibition of membrane binding and cross-linking. Immunological techniques establish N- and C-terminal fragments of presenilin-1 as specifically cross-linked polypeptides. Furthermore, binding of gamma-secretase inhibitors to embryonic membranes derived from presenilin-1 knockout embryos is reduced in a gene dose-dependent manner. In addition, C-terminal fragments of presenilin-2 are specifically cross-linked. Taken together, these results indicate that potent and selective gamma-secretase inhibitors block A beta formation by binding to presenilin-1 and -2.
Seiffert
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D
DuPont Pharmaceuticals Company, Wilmington, Delaware 19880, USA. Dietmar.A.Seiffert@DuPontpharma.com
Bradley
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Rominger
C M
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Rominger
D H
DH
Yang
F
F
Meredith
J E
JE
Wang
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Q
Roach
A H
AH
Thompson
L A
LA
Spitz
S M
SM
Higaki
J N
JN
Prakash
S R
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Combs
A P
AP
Copeland
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Arneric
S P
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Hartig
P R
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Robertson
D W
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Cordell
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Stern
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Olson
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Zaczek
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D053829:Amyloid Precursor Protein Secretases; D002462:Cell Membrane / Q000378:metabolism; D010450:Endopeptidases / Q000187:drug effects* / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D011233:Precipitin Tests; D053764:Presenilin-1; D053766:Presenilin-2; D013379:Substrate Specificity
D004791:Enzyme Inhibitors; D008565:Membrane Proteins; D053764:Presenilin-1; D053766:Presenilin-2; D053829:Amyloid Precursor Protein Secretases; D010450:Endopeptidases