Figure 2.
(A) Schematic of a fusion protein (HaloTag/R-GECO1.2) containing HaloTag (extracellular) and R-GECO1.2 (intracellular) linked by a transmembrane peptide. (B–E) Two-color imaging of cells transfected with HaloTag/R-GECO1.2 and labeled with fluorescent HaloTag substrates (1–2 μM) including HaloTag AF488 (B), Fluo HaloTag-1 (C), Fluo HaloTag-2 (D), or Fluo HaloTag-3 (E). The HaloTag substrates were cell impermeable so they only labeled HaloTag displayed on the cell surface. The fusion protein, however, was found to be localized at both the plasma and intracellular membranes after transient transfection. Scale bar = 5 μm.