Explore the activation efficiency of different ligand carriers on synNotch-based contact-dependent activation system

Abstract

Objectives: synNotch receptors can get different inputsabout the outside environment into cells; however, syn-Notch system doesn’t work for soluble ligands. This studyaims to explore the activation efficiency of different ligandcarriers on synNotch system.Methods: SynNotch-based contact-dependent activationsystem was constructed in 293T cells (293T-synNotch), thenthe synNotch receptor ligands eGFP proteins were providedby three different carriers: 400 nm Ni magnetic beads (MagNi-eGFP), 300 nm carboxyl modified Fe3O4 magnetic beads(Mag COOH-deGFP), and 4T1 cell (4T1-mGFP). Three eGFPcarriers were incubated with 293T-synNotch, the activationefficiencies of these three eGFP carriers were evaluated byfluorescence microscopy.Results: The 293T-synNotch cell activated by Mag Ni-eGFPshows no observable red fluorescence; when MagCOOH-deGFP are incubated with 293T-synNotch, about50‰cells with red fluorescence appeared, also eGFP proteinshave not dropped off from the Mag COOH-deGFPbeads; 4T1-mGFP cells show the highest activation efficiency,about 21% synNotch cells are activated, when 4T1--mGFP and 293T-synNotch are incubated at high cell density.Conclusion: The 4T1-mGFP cells are the most effective ligandsfor synNotch receptor activation.