title: Effect of valine on the efficiency and precision at S4 cleavage of the Notch-1 transmembrane domain.
abstract: Presenilin-dependent intramembranous proteolysis mediates the dual cleavage of the Notch-1 protein (S4 and S3) as well as the beta amyloid precursor protein (betaAPP) (gamma40 and epsilon-site). betaAPP has a valine residue just before the gamma40 (amyloid beta [Abeta] numbering) site and after the epsilon-site. Both gamma40 and epsilon have multiple cleavage sites, and the varieties of gamma40 cleavage are associated with Alzheimer's disease (AD). These lines of evidence suggest that valine plays a role in the intramembranous proteolysis. S4 cleavage in the middle of the Notch-1 transmembrane domain (TMD) corresponds to the gamma40 cleavage of betaAPP. The cleavage site is in the center of four sequential alanine residues between Ala1731 and Ala1732, neither of which has a valine residue. To investigate the effects of valine on presenilin-dependent intramembranous proteolysis, we replaced the transmembrane domain residue of Notch-1 with valine and analyzed the efficiency and precision at S4 and S3. We observed that all valine-mutated Notch-1 proteins have a dominant cleavage site (S4) between Ala1731 and Ala1732 with some variations of cleavage precision, suggesting that valine is not indispensable for determining the cleavage site of the Notch-1 transmembrane domain, but affects the efficiency and precision at S4 cleavage of the Notch-1 transmembrane domain.
authors.affiliation: Department of Psychiatry, Institute of Neuroscience, Mie University Graduate School of Medicine, Mie, Japan. h-tanii@clin.medic.mie-u.ac.jp
authors.forename: Hisashi
authors.initials: H
authors.lastname: Tanii
authors.forename: Jingwei
authors.initials: J
authors.lastname: Jiang
authors.forename: Akio
authors.initials: A
authors.lastname: Fukumori
authors.forename: Shinji
authors.initials: S
authors.lastname: Tagami
authors.forename: Yuji
authors.initials: Y
authors.lastname: Okazaki
authors.forename: Masayasu
authors.initials: M
authors.lastname: Okochi
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Takeda
mesh_terms: D000595:Amino Acid Sequence; D016564:Amyloid beta-Protein Precursor / Q000235:genetics / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western / Q000379:methods; D002461:Cell Line, Transformed; D002462:Cell Membrane / Q000378:metabolism; D006801:Humans; D047468:Immunoprecipitation / Q000379:methods; D051379:Mice; D016297:Mutagenesis, Site-Directed / Q000379:methods; D009154:Mutation; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D058255:Protease Nexins; D017434:Protein Structure, Tertiary / Q000502:physiology; D051881:Receptor, Notch1 / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000235:genetics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D014162:Transfection / Q000379:methods; D014633:Valine / Q000378:metabolism*
chemical_list: D016564:Amyloid beta-Protein Precursor; C497761:NOTCH1 protein, human; D010446:Peptide Fragments; D058255:Protease Nexins; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D014633:Valine