Presenilins mediate a dual intramembranous gamma-secretase cleavage of Notch-1.
Following ectodomain shedding, Notch-1 undergoes presenilin (PS)-dependent constitutive intramembranous endoproteolysis at site-3. This cleavage is similar to the PS-dependent gamma-secretase cleavage of the beta-amyloid precursor protein (betaAPP). However, topological differences in cleavage resulting in amyloid beta-peptide (Abeta) or the Notch-1 intracellular domain (NICD) indicated independent mechanisms of proteolytic cleavage. We now demonstrate the secretion of an N-terminal Notch-1 Abeta-like fragment (Nbeta). Analysis of Nbeta by MALDI-TOF MS revealed that Nbeta is cleaved at a novel site (site-4, S4) near the middle of the transmembrane domain. Like the corresponding cleavage of betaAPP at position 40 and 42 of the Abeta domain, S4 cleavage is PS dependent. The precision of this cleavage is affected by familial Alzheimer's disease-associated PS1 mutations similar to the pathological endoproteolysis of betaAPP. Considering these similarities between intramembranous processing of Notch and betaAPP, we conclude that these proteins are cleaved by a common mechanism utilizing the same protease, i.e. PS/gamma-secretase.
Okochi
Masayasu
M
Department of Post-Genomics and Diseases, Division of Psychiatry and Behavioral Proteomics, Osaka University Graduate School of Medicine, 565-0871 Osaka, Japan.
Steiner
Harald
H
Fukumori
Akio
A
Tanii
Hisashi
H
Tomita
Taisuke
T
Tanaka
Toshihisa
T
Iwatsubo
Takeshi
T
Kudo
Takashi
T
Takeda
Masatoshi
M
Haass
Christian
C
D000544:Alzheimer Disease / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D053829:Amyloid Precursor Protein Secretases; D016229:Amyloid beta-Peptides / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D000818:Animals; D016282:Aspartic Acid Endopeptidases; D001665:Binding Sites; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D010450:Endopeptidases / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D053764:Presenilin-1; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors
D016229:Amyloid beta-Peptides; D008565:Membrane Proteins; C497761:NOTCH1 protein, human; C497762:Notch1 protein, mouse; C508853:PSEN1 protein, human; D010446:Peptide Fragments; D053764:Presenilin-1; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D014157:Transcription Factors; D053829:Amyloid Precursor Protein Secretases; D010450:Endopeptidases; D016282:Aspartic Acid Endopeptidases; C509280:BACE1 protein, human; C509282:Bace1 protein, mouse