FIGURE 1.

Design of the YS2H system. a, a map of the YS2H vector is drawn with restriction enzyme sites and genes labeled. The bait protein is expressed as a fusion to Aga2 on cell surface, whereas the prey protein is expressed as a secretory form. b and c, schematic diagrams of the expression cassette and protein-protein interactions (acid base coiled coils) via the secretory pathway are depicted. The prey bound to the bait is detected by antibody binding to the Myc tag (b) or by direct GFP readout from split GFP complementation (c). FLAG (DYKDDDDK) and Myc (EQKLISEEDL) epitope tags are fused to the C-terminal of the bait and prey proteins, respectively, and are used to measure the surface expression of the bait and the amount of the prey that is bound to the bait. d, the deletion of signal sequence for the prey and bait proteins leads to their expression in the cytosol.