title: Membrane tethered delta activates notch and reveals a role for spatio-mechanical regulation of the signaling pathway.
abstract: Short-range Notch receptor signaling is necessary for coordinating developmental activities in metazoa. To investigate this juxtacrine pathway, we mimic receptor-ligand binding within the cell-cell junction by engaging Notch1-eGFP expressing cells to a supported lipid membrane displaying Delta-like protein 4 (DLL4). DLL4-Notch1 binding, oligomerization, and transport were observed in real time, and the molecular density and stoichiometry of the complexes were determined using quantitative fluorescence imaging. A Notch transcriptional reporter readout was used to quantify how ligand lateral mobility, orientation, and density modulate receptor activation levels. These experiments demonstrate that limiting the lateral mobility of DLL4 can enhance Notch activation by 2.6-fold, thus supporting the existence of a spatio-mechanical mechanism of signal regulation.
authors.affiliation: Department of Chemistry, Emory University, Atlanta, Georgia.
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Narui
authors.affiliation: Department of Chemistry, Emory University, Atlanta, Georgia. Electronic address: k.salaita@emory.edu.
authors.forename: Khalid
authors.initials: K
authors.lastname: Salaita
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D002135:Calcium-Binding Proteins; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008051:Lipid Bilayers / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D011485:Protein Binding; D051881:Receptor, Notch1 / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002135:Calcium-Binding Proteins; C519665:DLL4 protein, mouse; D047908:Intracellular Signaling Peptides and Proteins; D008051:Lipid Bilayers; D008565:Membrane Proteins; C497762:Notch1 protein, mouse; D051881:Receptor, Notch1