COPI transport requires membrane contact. Quantitative data are shown as mean ± SD, with the number of independent experiments indicated. Statistics was performed using the two-tailed Student’s t test: ****P < 0.0001, ***P < 0.001, ns (non-significant) P > 0.05. (A) COPI transport assay assessing the effect of 20 µM H89 treatment. The quantitation of a representative experiment is shown on the right, n = 3. Representative confocal images are shown on the left, VSVG-KDELR (green) and giantin (magenta), bar = 10 µm. (B) COPI transport assay assessing the effect of siRNA against VAP-A. The quantitation of a representative experiment is shown on the right, n = 4. Representative confocal images are shown on the left, VSVG-KDELR (green), giantin (magenta), bar = 10 µm. (C) COPI transport assay assessing the effect of siRNA against VAP-A followed by functional lipid rescue by feeding cells with different lengths of PC. Representative confocal images are shown in the lower panel, VSVG-KDELR (green) and giantin (magenta), bar = 10 µm. Quantitation of a representative experiment is shown in the upper panel, n = 4. (D) COPI transport assay assessing the effect of siRNA against VAP-A followed by functional lipid rescue by feeding cells with short forms of PE or PS. The quantitation of a representative experiment is shown in upper panel, n = 3. Representative confocal images are shown in lower panel, VSVG-KDELR (green) and giantin (magenta), bar = 10 µm.