Fig.1.

Gateway-based cloning and expression system. (A) An entry clone containing the leader peptide and extracellular domain (ECD) of interest is recombined via the LR reaction with a destination vector to generate an expression clone. This incorporates the ECD fused to EGFP, an Avitag biotin acceptor peptide, a PP cleavage site, and a GPI signal sequence. (B) Following expression in mammalian cells, surface-presented protein can be cleaved with PP and biotinylated with BirA either at the cell surface or following cleavage. This versatile cloning vector enables multiple assays with either cell-expressed or soluble versions of the protein of interest.