Depletion of PtdIns(3)P but not PtdIns(3,5)P₂ causes TgPH1 to dissociate from Rab5-positive membranes in COS-7 cells.

<p>A. Schematic of the rapamycin-induced dimerization system and the enzymatic activities of the FKBP-conjugated phosphatases. B, C. Time-lapse imaging of COS-7 cells expressing iRFP-FRB-Rab5 (magenta), mCherry-FKBP fused to the indicated enzyme (cyan) and eGFP^NES-TgPH1 (grayscale). B. The time-lapse shows the recruitment of the fused phosphatase (cyan) to Rab5-containing puncta (magenta) before and after the addition of 1 μM rapamycin, marked by time 0. C. A time-lapse series of the same cells showing the dynamics of eGFP^NES -TgPH1 before and after rapamycin. Images were acquired at 2 min intervals. The graphs at right show the normalized intensity at Rab5-positive membranes relative to the whole cell for FKBP-tagged enzymes (B) and eGFP^NES-TgPH1 (C). Data are means ±SEM of 41 (MTM1), 23 (C375S) or 27 (INPP5E) cells from 3 or 4 independent experiments. * p<0.05 against control using ANOVA and Tukey's test.