Fig. 4

Light-dependent translocation of PH-Akt-EGFP reporter in PC6-3 cells. a Top: Dr-TrkA is inactive in cells kept under 660 nm light. The 780 nm light causes activation of the Dr-TrkA and downstream phosphatidylinositol triphosphate (PIP3) kinase. This results in accumulation of PIP3 in the plasma membrane and recruiting of PH-Akt-EGFP reporter from the cytoplasm. Bottom: Schematic drawing of the bicistronic pPH-Akt-EGFP-IRES2-Dr-TrkA plasmid co-expressing PH-Akt-EGFP and Dr-TrkA. b Top: Epifluorescence image of the PC6-3 cell transfected with the bicistronic plasmid and kept under 660 nm light. Bottom: Epifluorescence image of the PC6-3 cell kept under 780 nm light for 10 min to reach steady-state Akt transition to the plasma membrane. Scale bar, 10 μm. c Steady-state intensity profile of PH-EGFP-Akt fluorescence of the PC6-3 cell kept under 660 nm light (red line) and illuminated by 780 nm light for 10 min (black line). d Relative decrease of cytoplasmic PH-Akt-EGFP fluorescence induced by 780 nm light (0.5 mW cm⁻²). e Relative increase of cytoplasmic PH-Akt-EGFP fluorescence induced by 660 nm light (0.5 mW cm⁻²). f Reversible translocation of the PH-Akt-EGFP reporter between the plasma membrane and cytoplasm in response to 780 nm and 660 nm illumination. Error bars represent s.d., n = 3 experiments