Mutations at the P1' position of Notch1 decrease intracellular domain stability rather than cleavage by gamma-secretase.
Gamma-secretase is a unique protease which cleaves within the transmembrane domain of several substrate proteins. Among gamma-secretase substrates are members of the Notch family of receptors and the amyloid precursor protein. In this study we used a cell-free Notch-cleavage assay and specific gamma-secretase inhibitors to study the cleavage of Notch by gamma-secretase. Using this assay, we found that, in contrast to previous reports, the presence of valine at the P1(') position of Notch1 is not required for gamma-secretase cleavage. Our results suggest that the presence of valine at the N-terminus of the Notch intracellular domain cleavage product is important for its stability. Thus it appears that Notch cleavage is very similar to APP cleavage with respect to the lack of sequence specificity.
Blat
Yuval
Y
Department of Chemical Enzymology, Bristol-Myers Squibb Company, The Experimental Station, Route 141 and Henry Clay Road, Wilmington, DE 19880, USA. yblat1@comcast.net
Meredith
Jere E
JE
Wang
Qian
Q
Bradley
Jodi D
JD
Thompson
Lorin A
LA
Olson
Richard E
RE
Stern
Andrew M
AM
Seiffert
Dietmar
D
D000111:Acetylcysteine / Q000031:analogs & derivatives* / Q000378:metabolism; D053829:Amyloid Precursor Protein Secretases; D000818:Animals; D016282:Aspartic Acid Endopeptidases; D002460:Cell Line; D002474:Cell-Free System; D002478:Cells, Cultured; D015853:Cysteine Proteinase Inhibitors / Q000378:metabolism; D010450:Endopeptidases / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D015394:Molecular Structure; D009154:Mutation; D017434:Protein Structure, Tertiary; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D014157:Transcription Factors; D014633:Valine / Q000378:metabolism
D015853:Cysteine Proteinase Inhibitors; D008565:Membrane Proteins; C497761:NOTCH1 protein, human; C497762:Notch1 protein, mouse; D051881:Receptor, Notch1; D011956:Receptors, Cell Surface; D014157:Transcription Factors; C067713:lactacystin; D053829:Amyloid Precursor Protein Secretases; D010450:Endopeptidases; D016282:Aspartic Acid Endopeptidases; C509280:BACE1 protein, human; C509282:Bace1 protein, mouse; D014633:Valine; D000111:Acetylcysteine