Monoubiquitination and Endocytosis Direct γ-Secretase Cleavage of Activated Notch Receptor

• Published in: The Journal of cell biology Vol. 166; no. 1; pp. 73 - 83
• Main Authors: Gupta-Rossi, Neetu, Six, Emmanuelle, LeBail, Odile, Logeat, Frédérique, Chastagner, Patricia, Olry, Annie, Israël, Alain, Brou, Christel
• Format: Journal Article
• Language: English
• Published: United States Rockefeller University Press 05.07.2004; The Rockefeller University Press
• Subjects: Amino Acid Sequence; Amyloid Precursor Protein Secretases; Animals; Antibodies; Aspartic Acid Endopeptidases; Cell Line; Cell membranes; Cells; Cellular Biology; Endocytosis; Endopeptidases; Endopeptidases - metabolism; Enzymes; HeLa Cells; Humans; Immunoblotting; Life Sciences; Ligands; Lysine; Lysine - chemistry; Membrane Proteins; Membrane Proteins - metabolism; Microscopy, Confocal; Microscopy, Fluorescence; Molecular Sequence Data; Molecules; Precipitin Tests; Presenilin-1; Presenilins; Protein Binding; Protein Structure, Tertiary; Receptors; Receptors, Notch; Sequence Homology, Amino Acid; Signal Transduction; Time Factors; Transfection; Ubiquitin; Ubiquitin - chemistry; Ubiquitin - metabolism; Ubiquitins
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.200310098

Activation of mammalian Notch receptor by its ligands induces TNFα-converting enzyme-dependent ectodomain shedding, followed by intramembrane proteolysis due to presenilin (PS)-dependent γ-secretase activity. Here, we demonstrate that a new modification, a monoubiquitination, as well as clathrin-dependent endocytosis, is required for γ-secretase processing of a constitutively active Notch derivative, ΔE, which mimics the TNFα-converting enzyme-processing product. PS interacts with this modified form of ΔE, Δ Eu. We identified the lysine residue targeted by the monoubiquitination event and confirmed its importance for activation of Notch receptor by its ligand, Deltalike 1. We propose a new model where monoubiquitination and endocytosis of Notch are a prerequisite for its PS-dependent cleavage, and discuss its relevance for other γ-secretase substrates.