Open AccessConservation of the biochemical mechanisms of signal transduction among mammalian Notch family members
Author(s) -
Tetsuya Mizutani,
Yoshihito Taniguchi,
Tomokazu Aoki,
Nobuo Hashimoto,
Tasuku Honjo
Publication year - 2001
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.161269998
Subject(s) - notch signaling pathway , notch proteins , presenilin , biology , microbiology and biotechnology , cytoplasm , signal transduction , amyloid precursor protein secretase , cell fate determination , transmembrane domain , transmembrane protein , extracellular , transcription factor , genetics , gene , amyloid precursor protein , receptor , alzheimer's disease , medicine , disease , pathology
Mouse Notch1, which plays an important role in cell fate determination in development, is proteolytically processed within its transmembrane domain by unidentified gamma-secretase-like activity that depends on presenilin. To study this proteolytic event, we established a cell-free Notch cleavage assay system using the membrane fraction of fibroblast transfectants of various Notch constructs with deletion of the extracellular portion (Notch DeltaE). The cytoplasmic portion of Notch1 DeltaE was released from the membrane upon incubation at 37 degrees C, which was inhibited by the specific gamma-secretase inhibitor, MW167, or by overexpression of dominant negative presenilin1. Likewise, other members of mouse Notch family were proteolytically cleaved in a presenilin-dependent, MW167-sensitive manner in vivo as well as in the cell-free Notch DeltaE cleavage assay system. All four members of the mouse Notch family migrated to the nucleus and activated the transcription from the promoter carrying the RBP-J consensus sequences after they were released from the membrane. These results demonstrate the conserved biochemical mechanism of signal transduction among mammalian Notch family members.